Merge pull request #1701 from karalabe/eth62-sync-rebase

eth: implement eth/62 synchronization logic

23 files changed, 3347 insertions, 1274 deletions

diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index ff556c984..dc7e19c61 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -283,6 +283,7 @@ JavaScript API. See https://github.com/ethereum/go-ethereum/wiki/Javascipt-Conso
 		utils.DataDirFlag,
 		utils.BlockchainVersionFlag,
 		utils.OlympicFlag,
+		utils.EthVersionFlag,
 		utils.CacheFlag,
 		utils.JSpathFlag,
 		utils.ListenPortFlag,
@@ -333,6 +334,7 @@ JavaScript API. See https://github.com/ethereum/go-ethereum/wiki/Javascipt-Conso
 	app.Before = func(ctx *cli.Context) error {
 		utils.SetupLogger(ctx)
 		utils.SetupVM(ctx)
+		utils.SetupEth(ctx)
 		if ctx.GlobalBool(utils.PProfEanbledFlag.Name) {
 			utils.StartPProf(ctx)
 		}
diff --git a/cmd/geth/monitorcmd.go b/cmd/geth/monitorcmd.go
index a7c099532..a45d29b8f 100644
--- a/cmd/geth/monitorcmd.go
+++ b/cmd/geth/monitorcmd.go
@@ -289,7 +289,7 @@ func updateChart(metric string, data []float64, base *int, chart *termui.LineCha
 		}
 	}
 	unit, scale := 0, 1.0
-	for high >= 1000 {
+	for high >= 1000 && unit+1 < len(dataUnits) {
 		high, unit, scale = high/1000, unit+1, scale*1000
 	}
 	// If the unit changes, re-create the chart (hack to set max height...)
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index af2929d10..80805ca22 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -138,6 +138,11 @@ var (
 		Name:  "olympic",
 		Usage: "Use olympic style protocol",
 	}
+	EthVersionFlag = cli.IntFlag{
+		Name:  "eth",
+		Value: 62,
+		Usage: "Highest eth protocol to advertise (temporary, dev option)",
+	}
 
 	// miner settings
 	MinerThreadsFlag = cli.IntFlag{
@@ -459,6 +464,18 @@ func SetupVM(ctx *cli.Context) {
 	vm.SetJITCacheSize(ctx.GlobalInt(VMJitCacheFlag.Name))
 }
 
+// SetupEth configures the eth packages global settings
+func SetupEth(ctx *cli.Context) {
+	version := ctx.GlobalInt(EthVersionFlag.Name)
+	for len(eth.ProtocolVersions) > 0 && eth.ProtocolVersions[0] > uint(version) {
+		eth.ProtocolVersions = eth.ProtocolVersions[1:]
+		eth.ProtocolLengths = eth.ProtocolLengths[1:]
+	}
+	if len(eth.ProtocolVersions) == 0 {
+		Fatalf("No valid eth protocols remaining")
+	}
+}
+
 // MakeChain creates a chain manager from set command line flags.
 func MakeChain(ctx *cli.Context) (chain *core.ChainManager, chainDb common.Database) {
 	datadir := ctx.GlobalString(DataDirFlag.Name)
diff --git a/core/types/block.go b/core/types/block.go
index 2188e6d4d..fd81db04c 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -360,6 +360,20 @@ func (b *Block) WithMiningResult(nonce uint64, mixDigest common.Hash) *Block {
 	}
 }
 
+// WithBody returns a new block with the given transaction and uncle contents.
+func (b *Block) WithBody(transactions []*Transaction, uncles []*Header) *Block {
+	block := &Block{
+		header:       copyHeader(b.header),
+		transactions: make([]*Transaction, len(transactions)),
+		uncles:       make([]*Header, len(uncles)),
+	}
+	copy(block.transactions, transactions)
+	for i := range uncles {
+		block.uncles[i] = copyHeader(uncles[i])
+	}
+	return block
+}
+
 // Implement pow.Block
 
 func (b *Block) Hash() common.Hash {
diff --git a/eth/backend.go b/eth/backend.go
index 2b21a7c96..ad2a2c1f9 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -373,7 +373,7 @@ func New(config *Config) (*Ethereum, error) {
 
 	eth.blockProcessor = core.NewBlockProcessor(chainDb, eth.pow, eth.chainManager, eth.EventMux())
 	eth.chainManager.SetProcessor(eth.blockProcessor)
-	eth.protocolManager = NewProtocolManager(config.NetworkId, eth.eventMux, eth.txPool, eth.pow, eth.chainManager)
+	eth.protocolManager = NewProtocolManager(config.NetworkId, eth.eventMux, eth.txPool, eth.pow, eth.chainManager, chainDb)
 
 	eth.miner = miner.New(eth, eth.EventMux(), eth.pow)
 	eth.miner.SetGasPrice(config.GasPrice)
diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index e3e22a784..574f2ba15 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -18,61 +18,64 @@
 package downloader
 
 import (
-	"bytes"
 	"errors"
 	"math"
 	"math/big"
-	"math/rand"
 	"sync"
 	"sync/atomic"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
-	"gopkg.in/fatih/set.v0"
 )
 
 const (
-	eth60 = 60 // Constant to check for old protocol support
-	eth61 = 61 // Constant to check for new protocol support
+	eth61 = 61 // Constant to check for old protocol support
+	eth62 = 62 // Constant to check for new protocol support
 )
 
 var (
-	MinHashFetch  = 512 // Minimum amount of hashes to not consider a peer stalling
-	MaxHashFetch  = 512 // Amount of hashes to be fetched per retrieval request
-	MaxBlockFetch = 128 // Amount of blocks to be fetched per retrieval request
-
-	hashTTL         = 5 * time.Second  // Time it takes for a hash request to time out
-	blockSoftTTL    = 3 * time.Second  // Request completion threshold for increasing or decreasing a peer's bandwidth
-	blockHardTTL    = 3 * blockSoftTTL // Maximum time allowance before a block request is considered expired
-	crossCheckCycle = time.Second      // Period after which to check for expired cross checks
-
-	maxQueuedHashes = 256 * 1024 // Maximum number of hashes to queue for import (DOS protection)
-	maxBannedHashes = 4096       // Number of bannable hashes before phasing old ones out
-	maxBlockProcess = 256        // Number of blocks to import at once into the chain
+	MaxHashFetch     = 512 // Amount of hashes to be fetched per retrieval request
+	MaxBlockFetch    = 128 // Amount of blocks to be fetched per retrieval request
+	MaxHeaderFetch   = 192 // Amount of block headers to be fetched per retrieval request
+	MaxBodyFetch     = 128 // Amount of block bodies to be fetched per retrieval request
+	MaxStateFetch    = 384 // Amount of node state values to allow fetching per request
+	MaxReceiptsFetch = 384 // Amount of transaction receipts to allow fetching per request
+
+	hashTTL      = 5 * time.Second  // [eth/61] Time it takes for a hash request to time out
+	blockSoftTTL = 3 * time.Second  // [eth/61] Request completion threshold for increasing or decreasing a peer's bandwidth
+	blockHardTTL = 3 * blockSoftTTL // [eth/61] Maximum time allowance before a block request is considered expired
+	headerTTL    = 5 * time.Second  // [eth/62] Time it takes for a header request to time out
+	bodySoftTTL  = 3 * time.Second  // [eth/62] Request completion threshold for increasing or decreasing a peer's bandwidth
+	bodyHardTTL  = 3 * bodySoftTTL  // [eth/62] Maximum time allowance before a block body request is considered expired
+
+	maxQueuedHashes  = 256 * 1024 // [eth/61] Maximum number of hashes to queue for import (DOS protection)
+	maxQueuedHeaders = 256 * 1024 // [eth/62] Maximum number of headers to queue for import (DOS protection)
+	maxBlockProcess  = 256        // Number of blocks to import at once into the chain
 )
 
 var (
-	errBusy             = errors.New("busy")
-	errUnknownPeer      = errors.New("peer is unknown or unhealthy")
-	errBadPeer          = errors.New("action from bad peer ignored")
-	errStallingPeer     = errors.New("peer is stalling")
-	errBannedHead       = errors.New("peer head hash already banned")
-	errNoPeers          = errors.New("no peers to keep download active")
-	errPendingQueue     = errors.New("pending items in queue")
-	errTimeout          = errors.New("timeout")
-	errEmptyHashSet     = errors.New("empty hash set by peer")
-	errPeersUnavailable = errors.New("no peers available or all peers tried for block download process")
-	errAlreadyInPool    = errors.New("hash already in pool")
-	errInvalidChain     = errors.New("retrieved hash chain is invalid")
-	errCrossCheckFailed = errors.New("block cross-check failed")
-	errCancelHashFetch  = errors.New("hash fetching canceled (requested)")
-	errCancelBlockFetch = errors.New("block downloading canceled (requested)")
-	errNoSyncActive     = errors.New("no sync active")
+	errBusy              = errors.New("busy")
+	errUnknownPeer       = errors.New("peer is unknown or unhealthy")
+	errBadPeer           = errors.New("action from bad peer ignored")
+	errStallingPeer      = errors.New("peer is stalling")
+	errNoPeers           = errors.New("no peers to keep download active")
+	errPendingQueue      = errors.New("pending items in queue")
+	errTimeout           = errors.New("timeout")
+	errEmptyHashSet      = errors.New("empty hash set by peer")
+	errEmptyHeaderSet    = errors.New("empty header set by peer")
+	errPeersUnavailable  = errors.New("no peers available or all peers tried for block download process")
+	errAlreadyInPool     = errors.New("hash already in pool")
+	errInvalidChain      = errors.New("retrieved hash chain is invalid")
+	errInvalidBody       = errors.New("retrieved block body is invalid")
+	errCancelHashFetch   = errors.New("hash fetching canceled (requested)")
+	errCancelBlockFetch  = errors.New("block downloading canceled (requested)")
+	errCancelHeaderFetch = errors.New("block header fetching canceled (requested)")
+	errCancelBodyFetch   = errors.New("block body downloading canceled (requested)")
+	errNoSyncActive      = errors.New("no sync active")
 )
 
 // hashCheckFn is a callback type for verifying a hash's presence in the local chain.
@@ -90,28 +93,36 @@ type chainInsertFn func(types.Blocks) (int, error)
 // peerDropFn is a callback type for dropping a peer detected as malicious.
 type peerDropFn func(id string)
 
+// hashPack is a batch of block hashes returned by a peer (eth/61).
+type hashPack struct {
+	peerId string
+	hashes []common.Hash
+}
+
+// blockPack is a batch of blocks returned by a peer (eth/61).
 type blockPack struct {
 	peerId string
 	blocks []*types.Block
 }
 
-type hashPack struct {
-	peerId string
-	hashes []common.Hash
+// headerPack is a batch of block headers returned by a peer.
+type headerPack struct {
+	peerId  string
+	headers []*types.Header
 }
 
-type crossCheck struct {
-	expire time.Time
-	parent common.Hash
+// bodyPack is a batch of block bodies returned by a peer.
+type bodyPack struct {
+	peerId       string
+	transactions [][]*types.Transaction
+	uncles       [][]*types.Header
 }
 
 type Downloader struct {
 	mux *event.TypeMux
 
-	queue  *queue                      // Scheduler for selecting the hashes to download
-	peers  *peerSet                    // Set of active peers from which download can proceed
-	checks map[common.Hash]*crossCheck // Pending cross checks to verify a hash chain
-	banned *set.Set                    // Set of hashes we've received and banned
+	queue *queue   // Scheduler for selecting the hashes to download
+	peers *peerSet // Set of active peers from which download can proceed
 
 	interrupt int32 // Atomic boolean to signal termination
 
@@ -136,12 +147,18 @@ type Downloader struct {
 
 	// Channels
 	newPeerCh chan *peer
-	hashCh    chan hashPack  // Channel receiving inbound hashes
-	blockCh   chan blockPack // Channel receiving inbound blocks
-	processCh chan bool      // Channel to signal the block fetcher of new or finished work
+	hashCh    chan hashPack   // [eth/61] Channel receiving inbound hashes
+	blockCh   chan blockPack  // [eth/61] Channel receiving inbound blocks
+	headerCh  chan headerPack // [eth/62] Channel receiving inbound block headers
+	bodyCh    chan bodyPack   // [eth/62] Channel receiving inbound block bodies
+	processCh chan bool       // Channel to signal the block fetcher of new or finished work
 
 	cancelCh   chan struct{} // Channel to cancel mid-flight syncs
 	cancelLock sync.RWMutex  // Lock to protect the cancel channel in delivers
+
+	// Testing hooks
+	bodyFetchHook   func([]*types.Header) // Method to call upon starting a block body fetch
+	chainInsertHook func([]*Block)        // Method to call upon inserting a chain of blocks (possibly in multiple invocations)
 }
 
 // Block is an origin-tagged blockchain block.
@@ -152,8 +169,7 @@ type Block struct {
 
 // New creates a new downloader to fetch hashes and blocks from remote peers.
 func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock blockRetrievalFn, headBlock headRetrievalFn, insertChain chainInsertFn, dropPeer peerDropFn) *Downloader {
-	// Create the base downloader
-	downloader := &Downloader{
+	return &Downloader{
 		mux:         mux,
 		queue:       newQueue(),
 		peers:       newPeerSet(),
@@ -165,14 +181,10 @@ func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock blockRetrievalFn, he
 		newPeerCh:   make(chan *peer, 1),
 		hashCh:      make(chan hashPack, 1),
 		blockCh:     make(chan blockPack, 1),
+		headerCh:    make(chan headerPack, 1),
+		bodyCh:      make(chan bodyPack, 1),
 		processCh:   make(chan bool, 1),
 	}
-	// Inject all the known bad hashes
-	downloader.banned = set.New()
-	for hash, _ := range core.BadHashes {
-		downloader.banned.Add(hash)
-	}
-	return downloader
 }
 
 // Stats retrieves the current status of the downloader.
@@ -205,15 +217,12 @@ func (d *Downloader) Synchronising() bool {
 
 // RegisterPeer injects a new download peer into the set of block source to be
 // used for fetching hashes and blocks from.
-func (d *Downloader) RegisterPeer(id string, version int, head common.Hash, getRelHashes relativeHashFetcherFn, getAbsHashes absoluteHashFetcherFn, getBlocks blockFetcherFn) error {
-	// If the peer wants to send a banned hash, reject
-	if d.banned.Has(head) {
-		glog.V(logger.Debug).Infoln("Register rejected, head hash banned:", id)
-		return errBannedHead
-	}
-	// Otherwise try to construct and register the peer
+func (d *Downloader) RegisterPeer(id string, version int, head common.Hash,
+	getRelHashes relativeHashFetcherFn, getAbsHashes absoluteHashFetcherFn, getBlocks blockFetcherFn, // eth/61 callbacks, remove when upgrading
+	getRelHeaders relativeHeaderFetcherFn, getAbsHeaders absoluteHeaderFetcherFn, getBlockBodies blockBodyFetcherFn) error {
+
 	glog.V(logger.Detail).Infoln("Registering peer", id)
-	if err := d.peers.Register(newPeer(id, version, head, getRelHashes, getAbsHashes, getBlocks)); err != nil {
+	if err := d.peers.Register(newPeer(id, version, head, getRelHashes, getAbsHashes, getBlocks, getRelHeaders, getAbsHeaders, getBlockBodies)); err != nil {
 		glog.V(logger.Error).Infoln("Register failed:", err)
 		return err
 	}
@@ -234,7 +243,7 @@ func (d *Downloader) UnregisterPeer(id string) error {
 // Synchronise tries to sync up our local block chain with a remote peer, both
 // adding various sanity checks as well as wrapping it with various log entries.
 func (d *Downloader) Synchronise(id string, head common.Hash, td *big.Int) {
-	glog.V(logger.Detail).Infof("Attempting synchronisation: %v, head 0x%x, TD %v", id, head[:4], td)
+	glog.V(logger.Detail).Infof("Attempting synchronisation: %v, head [%x…], TD %v", id, head[:4], td)
 
 	switch err := d.synchronise(id, head, td); err {
 	case nil:
@@ -243,7 +252,7 @@ func (d *Downloader) Synchronise(id string, head common.Hash, td *big.Int) {
 	case errBusy:
 		glog.V(logger.Detail).Infof("Synchronisation already in progress")
 
-	case errTimeout, errBadPeer, errStallingPeer, errBannedHead, errEmptyHashSet, errPeersUnavailable, errInvalidChain, errCrossCheckFailed:
+	case errTimeout, errBadPeer, errStallingPeer, errEmptyHashSet, errEmptyHeaderSet, errPeersUnavailable, errInvalidChain:
 		glog.V(logger.Debug).Infof("Removing peer %v: %v", id, err)
 		d.dropPeer(id)
 
@@ -269,10 +278,6 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int) error
 	}
 	defer atomic.StoreInt32(&d.synchronising, 0)
 
-	// If the head hash is banned, terminate immediately
-	if d.banned.Has(hash) {
-		return errBannedHead
-	}
 	// Post a user notification of the sync (only once per session)
 	if atomic.CompareAndSwapInt32(&d.notified, 0, 1) {
 		glog.V(logger.Info).Infoln("Block synchronisation started")
@@ -284,7 +289,6 @@ func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int) error
 	// Reset the queue and peer set to clean any internal leftover state
 	d.queue.Reset()
 	d.peers.Reset()
-	d.checks = make(map[common.Hash]*crossCheck)
 
 	// Create cancel channel for aborting mid-flight
 	d.cancelLock.Lock()
@@ -319,25 +323,37 @@ func (d *Downloader) syncWithPeer(p *peer, hash common.Hash, td *big.Int) (err e
 		}
 	}()
 
-	glog.V(logger.Debug).Infof("Synchronizing with the network using: %s, eth/%d", p.id, p.version)
-	switch p.version {
-	case eth60:
-		// Old eth/60 version, use reverse hash retrieval algorithm
-		if err = d.fetchHashes60(p, hash); err != nil {
+	glog.V(logger.Debug).Infof("Synchronising with the network using: %s [eth/%d]", p.id, p.version)
+	defer glog.V(logger.Debug).Infof("Synchronisation terminated")
+
+	switch {
+	case p.version == eth61:
+		// Old eth/61, use forward, concurrent hash and block retrieval algorithm
+		number, err := d.findAncestor61(p)
+		if err != nil {
 			return err
 		}
-		if err = d.fetchBlocks60(); err != nil {
+		errc := make(chan error, 2)
+		go func() { errc <- d.fetchHashes61(p, td, number+1) }()
+		go func() { errc <- d.fetchBlocks61(number + 1) }()
+
+		// If any fetcher fails, cancel the other
+		if err := <-errc; err != nil {
+			d.cancel()
+			<-errc
 			return err
 		}
-	case eth61:
-		// New eth/61, use forward, concurrent hash and block retrieval algorithm
+		return <-errc
+
+	case p.version >= eth62:
+		// New eth/62, use forward, concurrent header and block body retrieval algorithm
 		number, err := d.findAncestor(p)
 		if err != nil {
 			return err
 		}
 		errc := make(chan error, 2)
-		go func() { errc <- d.fetchHashes(p, td, number+1) }()
-		go func() { errc <- d.fetchBlocks(number + 1) }()
+		go func() { errc <- d.fetchHeaders(p, td, number+1) }()
+		go func() { errc <- d.fetchBodies(number + 1) }()
 
 		// If any fetcher fails, cancel the other
 		if err := <-errc; err != nil {
@@ -352,8 +368,6 @@ func (d *Downloader) syncWithPeer(p *peer, hash common.Hash, td *big.Int) (err e
 		glog.V(logger.Error).Infof("Unsupported eth protocol: %d", p.version)
 		return errBadPeer
 	}
-	glog.V(logger.Debug).Infoln("Synchronization completed")
-
 	return nil
 }
 
@@ -382,207 +396,274 @@ func (d *Downloader) Terminate() {
 	d.cancel()
 }
 
-// fetchHashes60 starts retrieving hashes backwards from a specific peer and hash,
-// up until it finds a common ancestor. If the source peer times out, alternative
-// ones are tried for continuation.
-func (d *Downloader) fetchHashes60(p *peer, h common.Hash) error {
-	var (
-		start  = time.Now()
-		active = p             // active peer will help determine the current active peer
-		head   = common.Hash{} // common and last hash
-
-		timeout     = time.NewTimer(0)                // timer to dump a non-responsive active peer
-		attempted   = make(map[string]bool)           // attempted peers will help with retries
-		crossTicker = time.NewTicker(crossCheckCycle) // ticker to periodically check expired cross checks
-	)
-	defer crossTicker.Stop()
-	defer timeout.Stop()
-
-	glog.V(logger.Debug).Infof("Downloading hashes (%x) from %s", h[:4], p.id)
-	<-timeout.C // timeout channel should be initially empty.
+// findAncestor61 tries to locate the common ancestor block of the local chain and
+// a remote peers blockchain. In the general case when our node was in sync and
+// on the correct chain, checking the top N blocks should already get us a match.
+// In the rare scenario when we ended up on a long reorganization (i.e. none of
+// the head blocks match), we do a binary search to find the common ancestor.
+func (d *Downloader) findAncestor61(p *peer) (uint64, error) {
+	glog.V(logger.Debug).Infof("%v: looking for common ancestor", p)
 
-	getHashes := func(from common.Hash) {
-		go active.getRelHashes(from)
-		timeout.Reset(hashTTL)
+	// Request out head blocks to short circuit ancestor location
+	head := d.headBlock().NumberU64()
+	from := int64(head) - int64(MaxHashFetch) + 1
+	if from < 0 {
+		from = 0
 	}
+	go p.getAbsHashes(uint64(from), MaxHashFetch)
 
-	// Add the hash to the queue, and start hash retrieval.
-	d.queue.Insert([]common.Hash{h}, false)
-	getHashes(h)
+	// Wait for the remote response to the head fetch
+	number, hash := uint64(0), common.Hash{}
+	timeout := time.After(hashTTL)
 
-	attempted[p.id] = true
 	for finished := false; !finished; {
 		select {
 		case <-d.cancelCh:
-			return errCancelHashFetch
+			return 0, errCancelHashFetch
 
 		case hashPack := <-d.hashCh:
-			// Make sure the active peer is giving us the hashes
-			if hashPack.peerId != active.id {
+			// Discard anything not from the origin peer
+			if hashPack.peerId != p.id {
 				glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
 				break
 			}
-			timeout.Stop()
-
 			// Make sure the peer actually gave something valid
-			if len(hashPack.hashes) == 0 {
-				glog.V(logger.Debug).Infof("Peer (%s) responded with empty hash set", active.id)
-				return errEmptyHashSet
+			hashes := hashPack.hashes
+			if len(hashes) == 0 {
+				glog.V(logger.Debug).Infof("%v: empty head hash set", p)
+				return 0, errEmptyHashSet
 			}
-			for index, hash := range hashPack.hashes {
-				if d.banned.Has(hash) {
-					glog.V(logger.Debug).Infof("Peer (%s) sent a known invalid chain", active.id)
-
-					d.queue.Insert(hashPack.hashes[:index+1], false)
-					if err := d.banBlocks(active.id, hash); err != nil {
-						glog.V(logger.Debug).Infof("Failed to ban batch of blocks: %v", err)
-					}
-					return errInvalidChain
+			// Check if a common ancestor was found
+			finished = true
+			for i := len(hashes) - 1; i >= 0; i-- {
+				if d.hasBlock(hashes[i]) {
+					number, hash = uint64(from)+uint64(i), hashes[i]
+					break
 				}
 			}
-			// Determine if we're done fetching hashes (queue up all pending), and continue if not done
-			done, index := false, 0
-			for index, head = range hashPack.hashes {
-				if d.hasBlock(head) || d.queue.GetBlock(head) != nil {
-					glog.V(logger.Debug).Infof("Found common hash %x", head[:4])
-					hashPack.hashes = hashPack.hashes[:index]
-					done = true
+
+		case <-d.blockCh:
+			// Out of bounds blocks received, ignore them
+
+		case <-d.headerCh:
+			// Out of bounds eth/62 block headers received, ignore them
+
+		case <-d.bodyCh:
+			// Out of bounds eth/62 block bodies received, ignore them
+
+		case <-timeout:
+			glog.V(logger.Debug).Infof("%v: head hash timeout", p)
+			return 0, errTimeout
+		}
+	}
+	// If the head fetch already found an ancestor, return
+	if !common.EmptyHash(hash) {
+		glog.V(logger.Debug).Infof("%v: common ancestor: #%d [%x…]", p, number, hash[:4])
+		return number, nil
+	}
+	// Ancestor not found, we need to binary search over our chain
+	start, end := uint64(0), head
+	for start+1 < end {
+		// Split our chain interval in two, and request the hash to cross check
+		check := (start + end) / 2
+
+		timeout := time.After(hashTTL)
+		go p.getAbsHashes(uint64(check), 1)
+
+		// Wait until a reply arrives to this request
+		for arrived := false; !arrived; {
+			select {
+			case <-d.cancelCh:
+				return 0, errCancelHashFetch
+
+			case hashPack := <-d.hashCh:
+				// Discard anything not from the origin peer
+				if hashPack.peerId != p.id {
+					glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
 					break
 				}
-			}
-			// Insert all the new hashes, but only continue if got something useful
-			inserts := d.queue.Insert(hashPack.hashes, false)
-			if len(inserts) == 0 && !done {
-				glog.V(logger.Debug).Infof("Peer (%s) responded with stale hashes", active.id)
-				return errBadPeer
-			}
-			if !done {
-				// Check that the peer is not stalling the sync
-				if len(inserts) < MinHashFetch {
-					return errStallingPeer
+				// Make sure the peer actually gave something valid
+				hashes := hashPack.hashes
+				if len(hashes) != 1 {
+					glog.V(logger.Debug).Infof("%v: invalid search hash set (%d)", p, len(hashes))
+					return 0, errBadPeer
+				}
+				arrived = true
+
+				// Modify the search interval based on the response
+				block := d.getBlock(hashes[0])
+				if block == nil {
+					end = check
+					break
 				}
-				// Try and fetch a random block to verify the hash batch
-				// Skip the last hash as the cross check races with the next hash fetch
-				cross := rand.Intn(len(inserts) - 1)
-				origin, parent := inserts[cross], inserts[cross+1]
-				glog.V(logger.Detail).Infof("Cross checking (%s) with %x/%x", active.id, origin, parent)
-
-				d.checks[origin] = &crossCheck{
-					expire: time.Now().Add(blockSoftTTL),
-					parent: parent,
+				if block.NumberU64() != check {
+					glog.V(logger.Debug).Infof("%v: non requested hash #%d [%x…], instead of #%d", p, block.NumberU64(), block.Hash().Bytes()[:4], check)
+					return 0, errBadPeer
 				}
-				go active.getBlocks([]common.Hash{origin})
+				start = check
 
-				// Also fetch a fresh batch of hashes
-				getHashes(head)
-				continue
-			}
-			// We're done, prepare the download cache and proceed pulling the blocks
-			offset := uint64(0)
-			if block := d.getBlock(head); block != nil {
-				offset = block.NumberU64() + 1
-			}
-			d.queue.Prepare(offset)
-			finished = true
+			case <-d.blockCh:
+				// Out of bounds blocks received, ignore them
 
-		case blockPack := <-d.blockCh:
-			// Cross check the block with the random verifications
-			if blockPack.peerId != active.id || len(blockPack.blocks) != 1 {
-				continue
+			case <-d.headerCh:
+				// Out of bounds eth/62 block headers received, ignore them
+
+			case <-d.bodyCh:
+				// Out of bounds eth/62 block bodies received, ignore them
+
+			case <-timeout:
+				glog.V(logger.Debug).Infof("%v: search hash timeout", p)
+				return 0, errTimeout
 			}
-			block := blockPack.blocks[0]
-			if check, ok := d.checks[block.Hash()]; ok {
-				if block.ParentHash() != check.parent {
-					return errCrossCheckFailed
-				}
-				delete(d.checks, block.Hash())
+		}
+	}
+	return start, nil
+}
+
+// fetchHashes61 keeps retrieving hashes from the requested number, until no more
+// are returned, potentially throttling on the way.
+func (d *Downloader) fetchHashes61(p *peer, td *big.Int, from uint64) error {
+	glog.V(logger.Debug).Infof("%v: downloading hashes from #%d", p, from)
+
+	// Create a timeout timer, and the associated hash fetcher
+	request := time.Now()       // time of the last fetch request
+	timeout := time.NewTimer(0) // timer to dump a non-responsive active peer
+	<-timeout.C                 // timeout channel should be initially empty
+	defer timeout.Stop()
+
+	getHashes := func(from uint64) {
+		glog.V(logger.Detail).Infof("%v: fetching %d hashes from #%d", p, MaxHashFetch, from)
+
+		go p.getAbsHashes(from, MaxHashFetch)
+		request = time.Now()
+		timeout.Reset(hashTTL)
+	}
+	// Start pulling hashes, until all are exhausted
+	getHashes(from)
+	gotHashes := false
+
+	for {
+		select {
+		case <-d.cancelCh:
+			return errCancelHashFetch
+
+		case <-d.headerCh:
+			// Out of bounds eth/62 block headers received, ignore them
+
+		case <-d.bodyCh:
+			// Out of bounds eth/62 block bodies received, ignore them
+
+		case hashPack := <-d.hashCh:
+			// Make sure the active peer is giving us the hashes
+			if hashPack.peerId != p.id {
+				glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
+				break
 			}
+			hashReqTimer.UpdateSince(request)
+			timeout.Stop()
 
-		case <-crossTicker.C:
-			// Iterate over all the cross checks and fail the hash chain if they're not verified
-			for hash, check := range d.checks {
-				if time.Now().After(check.expire) {
-					glog.V(logger.Debug).Infof("Cross check timeout for %x", hash)
-					return errCrossCheckFailed
+			// If no more hashes are inbound, notify the block fetcher and return
+			if len(hashPack.hashes) == 0 {
+				glog.V(logger.Debug).Infof("%v: no available hashes", p)
+
+				select {
+				case d.processCh <- false:
+				case <-d.cancelCh:
+				}
+				// If no hashes were retrieved at all, the peer violated it's TD promise that it had a
+				// better chain compared to ours. The only exception is if it's promised blocks were
+				// already imported by other means (e.g. fecher):
+				//
+				// R <remote peer>, L <local node>: Both at block 10
+				// R: Mine block 11, and propagate it to L
+				// L: Queue block 11 for import
+				// L: Notice that R's head and TD increased compared to ours, start sync
+				// L: Import of block 11 finishes
+				// L: Sync begins, and finds common ancestor at 11
+				// L: Request new hashes up from 11 (R's TD was higher, it must have something)
+				// R: Nothing to give
+				if !gotHashes && td.Cmp(d.headBlock().Td) > 0 {
+					return errStallingPeer
 				}
+				return nil
 			}
+			gotHashes = true
 
-		case <-timeout.C:
-			glog.V(logger.Debug).Infof("Peer (%s) didn't respond in time for hash request", p.id)
-
-			var p *peer // p will be set if a peer can be found
-			// Attempt to find a new peer by checking inclusion of peers best hash in our
-			// already fetched hash list. This can't guarantee 100% correctness but does
-			// a fair job. This is always either correct or false incorrect.
-			for _, peer := range d.peers.AllPeers() {
-				if d.queue.Has(peer.head) && !attempted[peer.id] {
-					p = peer
-					break
-				}
+			// Otherwise insert all the new hashes, aborting in case of junk
+			glog.V(logger.Detail).Infof("%v: inserting %d hashes from #%d", p, len(hashPack.hashes), from)
+
+			inserts := d.queue.Insert61(hashPack.hashes, true)
+			if len(inserts) != len(hashPack.hashes) {
+				glog.V(logger.Debug).Infof("%v: stale hashes", p)
+				return errBadPeer
+			}
+			// Notify the block fetcher of new hashes, but stop if queue is full
+			cont := d.queue.Pending() < maxQueuedHashes
+			select {
+			case d.processCh <- cont:
+			default:
 			}
-			// if all peers have been tried, abort the process entirely or if the hash is
-			// the zero hash.
-			if p == nil || (head == common.Hash{}) {
-				return errTimeout
+			if !cont {
+				return nil
 			}
-			// set p to the active peer. this will invalidate any hashes that may be returned
-			// by our previous (delayed) peer.
-			active = p
-			getHashes(head)
-			glog.V(logger.Debug).Infof("Hash fetching switched to new peer(%s)", p.id)
+			// Queue not yet full, fetch the next batch
+			from += uint64(len(hashPack.hashes))
+			getHashes(from)
+
+		case <-timeout.C:
+			glog.V(logger.Debug).Infof("%v: hash request timed out", p)
+			hashTimeoutMeter.Mark(1)
+			return errTimeout
 		}
 	}
-	glog.V(logger.Debug).Infof("Downloaded hashes (%d) in %v", d.queue.Pending(), time.Since(start))
-
-	return nil
 }
 
-// fetchBlocks60 iteratively downloads the entire schedules block-chain, taking
-// any available peers, reserving a chunk of blocks for each, wait for delivery
-// and periodically checking for timeouts.
-func (d *Downloader) fetchBlocks60() error {
-	glog.V(logger.Debug).Infoln("Downloading", d.queue.Pending(), "block(s)")
-	start := time.Now()
+// fetchBlocks61 iteratively downloads the scheduled hashes, taking any available
+// peers, reserving a chunk of blocks for each, waiting for delivery and also
+// periodically checking for timeouts.
+func (d *Downloader) fetchBlocks61(from uint64) error {
+	glog.V(logger.Debug).Infof("Downloading blocks from #%d", from)
+	defer glog.V(logger.Debug).Infof("Block download terminated")
 
-	// Start a ticker to continue throttled downloads and check for bad peers
-	ticker := time.NewTicker(20 * time.Millisecond)
+	// Create a timeout timer for scheduling expiration tasks
+	ticker := time.NewTicker(100 * time.Millisecond)
 	defer ticker.Stop()
 
-out:
+	update := make(chan struct{}, 1)
+
+	// Prepare the queue and fetch blocks until the hash fetcher's done
+	d.queue.Prepare(from)
+	finished := false
+
 	for {
 		select {
 		case <-d.cancelCh:
 			return errCancelBlockFetch
 
-		case <-d.hashCh:
-			// Out of bounds hashes received, ignore them
+		case <-d.headerCh:
+			// Out of bounds eth/62 block headers received, ignore them
+
+		case <-d.bodyCh:
+			// Out of bounds eth/62 block bodies received, ignore them
 
 		case blockPack := <-d.blockCh:
-			// Short circuit if it's a stale cross check
-			if len(blockPack.blocks) == 1 {
-				block := blockPack.blocks[0]
-				if _, ok := d.checks[block.Hash()]; ok {
-					delete(d.checks, block.Hash())
-					break
-				}
-			}
 			// If the peer was previously banned and failed to deliver it's pack
 			// in a reasonable time frame, ignore it's message.
 			if peer := d.peers.Peer(blockPack.peerId); peer != nil {
 				// Deliver the received chunk of blocks, and demote in case of errors
-				err := d.queue.Deliver(blockPack.peerId, blockPack.blocks)
+				err := d.queue.Deliver61(blockPack.peerId, blockPack.blocks)
 				switch err {
 				case nil:
 					// If no blocks were delivered, demote the peer (need the delivery above)
 					if len(blockPack.blocks) == 0 {
 						peer.Demote()
-						peer.SetIdle()
+						peer.SetIdle61()
 						glog.V(logger.Detail).Infof("%s: no blocks delivered", peer)
 						break
 					}
 					// All was successful, promote the peer and potentially start processing
 					peer.Promote()
-					peer.SetIdle()
+					peer.SetIdle61()
 					glog.V(logger.Detail).Infof("%s: delivered %d blocks", peer, len(blockPack.blocks))
 					go d.process()
 
@@ -594,7 +675,7 @@ out:
 					// Peer probably timed out with its delivery but came through
 					// in the end, demote, but allow to to pull from this peer.
 					peer.Demote()
-					peer.SetIdle()
+					peer.SetIdle61()
 					glog.V(logger.Detail).Infof("%s: out of bound delivery", peer)
 
 				case errStaleDelivery:
@@ -608,88 +689,101 @@ out:
 				default:
 					// Peer did something semi-useful, demote but keep it around
 					peer.Demote()
-					peer.SetIdle()
+					peer.SetIdle61()
 					glog.V(logger.Detail).Infof("%s: delivery partially failed: %v", peer, err)
 					go d.process()
 				}
 			}
+			// Blocks arrived, try to update the progress
+			select {
+			case update <- struct{}{}:
+			default:
+			}
+
+		case cont := <-d.processCh:
+			// The hash fetcher sent a continuation flag, check if it's done
+			if !cont {
+				finished = true
+			}
+			// Hashes arrive, try to update the progress
+			select {
+			case update <- struct{}{}:
+			default:
+			}
 
 		case <-ticker.C:
+			// Sanity check update the progress
+			select {
+			case update <- struct{}{}:
+			default:
+			}
+
+		case <-update:
 			// Short circuit if we lost all our peers
 			if d.peers.Len() == 0 {
 				return errNoPeers
 			}
 			// Check for block request timeouts and demote the responsible peers
-			badPeers := d.queue.Expire(blockHardTTL)
-			for _, pid := range badPeers {
+			for _, pid := range d.queue.Expire(blockHardTTL) {
 				if peer := d.peers.Peer(pid); peer != nil {
 					peer.Demote()
 					glog.V(logger.Detail).Infof("%s: block delivery timeout", peer)
 				}
 			}
-			// If there are unrequested hashes left start fetching from the available peers
-			if d.queue.Pending() > 0 {
-				// Throttle the download if block cache is full and waiting processing
+			// If there's noting more to fetch, wait or terminate
+			if d.queue.Pending() == 0 {
+				if d.queue.InFlight() == 0 && finished {
+					glog.V(logger.Debug).Infof("Block fetching completed")
+					return nil
+				}
+				break
+			}
+			// Send a download request to all idle peers, until throttled
+			for _, peer := range d.peers.IdlePeers() {
+				// Short circuit if throttling activated
 				if d.queue.Throttle() {
 					break
 				}
-				// Send a download request to all idle peers, until throttled
-				idlePeers := d.peers.IdlePeers()
-				for _, peer := range idlePeers {
-					// Short circuit if throttling activated since above
-					if d.queue.Throttle() {
-						break
-					}
-					// Get a possible chunk. If nil is returned no chunk
-					// could be returned due to no hashes available.
-					request := d.queue.Reserve(peer, peer.Capacity())
-					if request == nil {
-						continue
-					}
-					if glog.V(logger.Detail) {
-						glog.Infof("%s: requesting %d blocks", peer, len(request.Hashes))
-					}
-					// Fetch the chunk and check for error. If the peer was somehow
-					// already fetching a chunk due to a bug, it will be returned to
-					// the queue
-					if err := peer.Fetch(request); err != nil {
-						glog.V(logger.Error).Infof("Peer %s received double work", peer.id)
-						d.queue.Cancel(request)
-					}
+				// Reserve a chunk of hashes for a peer. A nil can mean either that
+				// no more hashes are available, or that the peer is known not to
+				// have them.
+				request := d.queue.Reserve61(peer, peer.Capacity())
+				if request == nil {
+					continue
 				}
-				// Make sure that we have peers available for fetching. If all peers have been tried
-				// and all failed throw an error
-				if d.queue.InFlight() == 0 {
-					return errPeersUnavailable
+				if glog.V(logger.Detail) {
+					glog.Infof("%s: requesting %d blocks", peer, len(request.Hashes))
 				}
-
-			} else if d.queue.InFlight() == 0 {
-				// When there are no more queue and no more in flight, We can
-				// safely assume we're done. Another part of the process will  check
-				// for parent errors and will re-request anything that's missing
-				break out
+				// Fetch the chunk and make sure any errors return the hashes to the queue
+				if err := peer.Fetch61(request); err != nil {
+					glog.V(logger.Error).Infof("%v: fetch failed, rescheduling", peer)
+					d.queue.Cancel(request)
+				}
+			}
+			// Make sure that we have peers available for fetching. If all peers have been tried
+			// and all failed throw an error
+			if !d.queue.Throttle() && d.queue.InFlight() == 0 {
+				return errPeersUnavailable
 			}
 		}
 	}
-	glog.V(logger.Detail).Infoln("Downloaded block(s) in", time.Since(start))
-	return nil
 }
 
 // findAncestor tries to locate the common ancestor block of the local chain and
 // a remote peers blockchain. In the general case when our node was in sync and
 // on the correct chain, checking the top N blocks should already get us a match.
-// In the rare scenario when we ended up on a long soft fork (i.e. none of the
-// head blocks match), we do a binary search to find the common ancestor.
+// In the rare scenario when we ended up on a long reorganization (i.e. none of
+// the head blocks match), we do a binary search to find the common ancestor.
 func (d *Downloader) findAncestor(p *peer) (uint64, error) {
 	glog.V(logger.Debug).Infof("%v: looking for common ancestor", p)
 
-	// Request out head blocks to short circuit ancestor location
+	// Request our head blocks to short circuit ancestor location
 	head := d.headBlock().NumberU64()
-	from := int64(head) - int64(MaxHashFetch)
+	from := int64(head) - int64(MaxHeaderFetch) + 1
 	if from < 0 {
 		from = 0
 	}
-	go p.getAbsHashes(uint64(from), MaxHashFetch)
+	go p.getAbsHeaders(uint64(from), MaxHeaderFetch, 0, false)
 
 	// Wait for the remote response to the head fetch
 	number, hash := uint64(0), common.Hash{}
@@ -700,38 +794,44 @@ func (d *Downloader) findAncestor(p *peer) (uint64, error) {
 		case <-d.cancelCh:
 			return 0, errCancelHashFetch
 
-		case hashPack := <-d.hashCh:
+		case headerPack := <-d.headerCh:
 			// Discard anything not from the origin peer
-			if hashPack.peerId != p.id {
-				glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
+			if headerPack.peerId != p.id {
+				glog.V(logger.Debug).Infof("Received headers from incorrect peer(%s)", headerPack.peerId)
 				break
 			}
 			// Make sure the peer actually gave something valid
-			hashes := hashPack.hashes
-			if len(hashes) == 0 {
-				glog.V(logger.Debug).Infof("%v: empty head hash set", p)
-				return 0, errEmptyHashSet
+			headers := headerPack.headers
+			if len(headers) == 0 {
+				glog.V(logger.Debug).Infof("%v: empty head header set", p)
+				return 0, errEmptyHeaderSet
 			}
 			// Check if a common ancestor was found
 			finished = true
-			for i := len(hashes) - 1; i >= 0; i-- {
-				if d.hasBlock(hashes[i]) {
-					number, hash = uint64(from)+uint64(i), hashes[i]
+			for i := len(headers) - 1; i >= 0; i-- {
+				if d.hasBlock(headers[i].Hash()) {
+					number, hash = headers[i].Number.Uint64(), headers[i].Hash()
 					break
 				}
 			}
 
+		case <-d.bodyCh:
+			// Out of bounds block bodies received, ignore them
+
+		case <-d.hashCh:
+			// Out of bounds eth/61 hashes received, ignore them
+
 		case <-d.blockCh:
-			// Out of bounds blocks received, ignore them
+			// Out of bounds eth/61 blocks received, ignore them
 
 		case <-timeout:
-			glog.V(logger.Debug).Infof("%v: head hash timeout", p)
+			glog.V(logger.Debug).Infof("%v: head header timeout", p)
 			return 0, errTimeout
 		}
 	}
 	// If the head fetch already found an ancestor, return
 	if !common.EmptyHash(hash) {
-		glog.V(logger.Debug).Infof("%v: common ancestor: #%d [%x]", p, number, hash[:4])
+		glog.V(logger.Debug).Infof("%v: common ancestor: #%d [%x…]", p, number, hash[:4])
 		return number, nil
 	}
 	// Ancestor not found, we need to binary search over our chain
@@ -741,7 +841,7 @@ func (d *Downloader) findAncestor(p *peer) (uint64, error) {
 		check := (start + end) / 2
 
 		timeout := time.After(hashTTL)
-		go p.getAbsHashes(uint64(check), 1)
+		go p.getAbsHeaders(uint64(check), 1, 0, false)
 
 		// Wait until a reply arrives to this request
 		for arrived := false; !arrived; {
@@ -749,37 +849,43 @@ func (d *Downloader) findAncestor(p *peer) (uint64, error) {
 			case <-d.cancelCh:
 				return 0, errCancelHashFetch
 
-			case hashPack := <-d.hashCh:
+			case headerPack := <-d.headerCh:
 				// Discard anything not from the origin peer
-				if hashPack.peerId != p.id {
-					glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
+				if headerPack.peerId != p.id {
+					glog.V(logger.Debug).Infof("Received headers from incorrect peer(%s)", headerPack.peerId)
 					break
 				}
 				// Make sure the peer actually gave something valid
-				hashes := hashPack.hashes
-				if len(hashes) != 1 {
-					glog.V(logger.Debug).Infof("%v: invalid search hash set (%d)", p, len(hashes))
+				headers := headerPack.headers
+				if len(headers) != 1 {
+					glog.V(logger.Debug).Infof("%v: invalid search header set (%d)", p, len(headers))
 					return 0, errBadPeer
 				}
 				arrived = true
 
 				// Modify the search interval based on the response
-				block := d.getBlock(hashes[0])
+				block := d.getBlock(headers[0].Hash())
 				if block == nil {
 					end = check
 					break
 				}
 				if block.NumberU64() != check {
-					glog.V(logger.Debug).Infof("%v: non requested hash #%d [%x], instead of #%d", p, block.NumberU64(), block.Hash().Bytes()[:4], check)
+					glog.V(logger.Debug).Infof("%v: non requested header #%d [%x…], instead of #%d", p, block.NumberU64(), block.Hash().Bytes()[:4], check)
 					return 0, errBadPeer
 				}
 				start = check
 
+			case <-d.bodyCh:
+				// Out of bounds block bodies received, ignore them
+
+			case <-d.hashCh:
+				// Out of bounds eth/61 hashes received, ignore them
+
 			case <-d.blockCh:
-				// Out of bounds blocks received, ignore them
+				// Out of bounds eth/61 blocks received, ignore them
 
 			case <-timeout:
-				glog.V(logger.Debug).Infof("%v: search hash timeout", p)
+				glog.V(logger.Debug).Infof("%v: search header timeout", p)
 				return 0, errTimeout
 			}
 		}
@@ -787,48 +893,58 @@ func (d *Downloader) findAncestor(p *peer) (uint64, error) {
 	return start, nil
 }
 
-// fetchHashes keeps retrieving hashes from the requested number, until no more
+// fetchHeaders keeps retrieving headers from the requested number, until no more
 // are returned, potentially throttling on the way.
-func (d *Downloader) fetchHashes(p *peer, td *big.Int, from uint64) error {
-	glog.V(logger.Debug).Infof("%v: downloading hashes from #%d", p, from)
+func (d *Downloader) fetchHeaders(p *peer, td *big.Int, from uint64) error {
+	glog.V(logger.Debug).Infof("%v: downloading headers from #%d", p, from)
+	defer glog.V(logger.Debug).Infof("%v: header download terminated", p)
 
 	// Create a timeout timer, and the associated hash fetcher
+	request := time.Now()       // time of the last fetch request
 	timeout := time.NewTimer(0) // timer to dump a non-responsive active peer
 	<-timeout.C                 // timeout channel should be initially empty
 	defer timeout.Stop()
 
-	getHashes := func(from uint64) {
-		glog.V(logger.Detail).Infof("%v: fetching %d hashes from #%d", p, MaxHashFetch, from)
+	getHeaders := func(from uint64) {
+		glog.V(logger.Detail).Infof("%v: fetching %d headers from #%d", p, MaxHeaderFetch, from)
 
-		go p.getAbsHashes(from, MaxHashFetch)
-		timeout.Reset(hashTTL)
+		go p.getAbsHeaders(from, MaxHeaderFetch, 0, false)
+		request = time.Now()
+		timeout.Reset(headerTTL)
 	}
-	// Start pulling hashes, until all are exhausted
-	getHashes(from)
-	gotHashes := false
+	// Start pulling headers, until all are exhausted
+	getHeaders(from)
+	gotHeaders := false
 
 	for {
 		select {
 		case <-d.cancelCh:
-			return errCancelHashFetch
+			return errCancelHeaderFetch
 
-		case hashPack := <-d.hashCh:
-			// Make sure the active peer is giving us the hashes
-			if hashPack.peerId != p.id {
-				glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", hashPack.peerId)
+		case <-d.hashCh:
+			// Out of bounds eth/61 hashes received, ignore them
+
+		case <-d.blockCh:
+			// Out of bounds eth/61 blocks received, ignore them
+
+		case headerPack := <-d.headerCh:
+			// Make sure the active peer is giving us the headers
+			if headerPack.peerId != p.id {
+				glog.V(logger.Debug).Infof("Received headers from incorrect peer (%s)", headerPack.peerId)
 				break
 			}
+			headerReqTimer.UpdateSince(request)
 			timeout.Stop()
 
-			// If no more hashes are inbound, notify the block fetcher and return
-			if len(hashPack.hashes) == 0 {
-				glog.V(logger.Debug).Infof("%v: no available hashes", p)
+			// If no more headers are inbound, notify the body fetcher and return
+			if len(headerPack.headers) == 0 {
+				glog.V(logger.Debug).Infof("%v: no available headers", p)
 
 				select {
 				case d.processCh <- false:
 				case <-d.cancelCh:
 				}
-				// If no hashes were retrieved at all, the peer violated it's TD promise that it had a
+				// If no headers were retrieved at all, the peer violated it's TD promise that it had a
 				// better chain compared to ours. The only exception is if it's promised blocks were
 				// already imported by other means (e.g. fecher):
 				//
@@ -838,25 +954,25 @@ func (d *Downloader) fetchHashes(p *peer, td *big.Int, from uint64) error {
 				// L: Notice that R's head and TD increased compared to ours, start sync
 				// L: Import of block 11 finishes
 				// L: Sync begins, and finds common ancestor at 11
-				// L: Request new hashes up from 11 (R's TD was higher, it must have something)
+				// L: Request new headers up from 11 (R's TD was higher, it must have something)
 				// R: Nothing to give
-				if !gotHashes && td.Cmp(d.headBlock().Td) > 0 {
+				if !gotHeaders && td.Cmp(d.headBlock().Td) > 0 {
 					return errStallingPeer
 				}
 				return nil
 			}
-			gotHashes = true
+			gotHeaders = true
 
-			// Otherwise insert all the new hashes, aborting in case of junk
-			glog.V(logger.Detail).Infof("%v: inserting %d hashes from #%d", p, len(hashPack.hashes), from)
+			// Otherwise insert all the new headers, aborting in case of junk
+			glog.V(logger.Detail).Infof("%v: inserting %d headers from #%d", p, len(headerPack.headers), from)
 
-			inserts := d.queue.Insert(hashPack.hashes, true)
-			if len(inserts) != len(hashPack.hashes) {
-				glog.V(logger.Debug).Infof("%v: stale hashes", p)
+			inserts := d.queue.Insert(headerPack.headers)
+			if len(inserts) != len(headerPack.headers) {
+				glog.V(logger.Debug).Infof("%v: stale headers", p)
 				return errBadPeer
 			}
-			// Notify the block fetcher of new hashes, but stop if queue is full
-			cont := d.queue.Pending() < maxQueuedHashes
+			// Notify the block fetcher of new headers, but stop if queue is full
+			cont := d.queue.Pending() < maxQueuedHeaders
 			select {
 			case d.processCh <- cont:
 			default:
@@ -865,22 +981,31 @@ func (d *Downloader) fetchHashes(p *peer, td *big.Int, from uint64) error {
 				return nil
 			}
 			// Queue not yet full, fetch the next batch
-			from += uint64(len(hashPack.hashes))
-			getHashes(from)
+			from += uint64(len(headerPack.headers))
+			getHeaders(from)
 
 		case <-timeout.C:
-			glog.V(logger.Debug).Infof("%v: hash request timed out", p)
-			return errTimeout
+			// Header retrieval timed out, consider the peer bad and drop
+			glog.V(logger.Debug).Infof("%v: header request timed out", p)
+			headerTimeoutMeter.Mark(1)
+			d.dropPeer(p.id)
+
+			// Finish the sync gracefully instead of dumping the gathered data though
+			select {
+			case d.processCh <- false:
+			default:
+			}
+			return nil
 		}
 	}
 }
 
-// fetchBlocks iteratively downloads the scheduled hashes, taking any available
-// peers, reserving a chunk of blocks for each, waiting for delivery and also
-// periodically checking for timeouts.
-func (d *Downloader) fetchBlocks(from uint64) error {
-	glog.V(logger.Debug).Infof("Downloading blocks from #%d", from)
-	defer glog.V(logger.Debug).Infof("Block download terminated")
+// fetchBodies iteratively downloads the scheduled block bodies, taking any
+// available peers, reserving a chunk of blocks for each, waiting for delivery
+// and also periodically checking for timeouts.
+func (d *Downloader) fetchBodies(from uint64) error {
+	glog.V(logger.Debug).Infof("Downloading block bodies from #%d", from)
+	defer glog.V(logger.Debug).Infof("Block body download terminated")
 
 	// Create a timeout timer for scheduling expiration tasks
 	ticker := time.NewTicker(100 * time.Millisecond)
@@ -888,7 +1013,7 @@ func (d *Downloader) fetchBlocks(from uint64) error {
 
 	update := make(chan struct{}, 1)
 
-	// Prepare the queue and fetch blocks until the hash fetcher's done
+	// Prepare the queue and fetch block bodies until the block header fetcher's done
 	d.queue.Prepare(from)
 	finished := false
 
@@ -897,31 +1022,42 @@ func (d *Downloader) fetchBlocks(from uint64) error {
 		case <-d.cancelCh:
 			return errCancelBlockFetch
 
-		case blockPack := <-d.blockCh:
+		case <-d.hashCh:
+			// Out of bounds eth/61 hashes received, ignore them
+
+		case <-d.blockCh:
+			// Out of bounds eth/61 blocks received, ignore them
+
+		case bodyPack := <-d.bodyCh:
 			// If the peer was previously banned and failed to deliver it's pack
 			// in a reasonable time frame, ignore it's message.
-			if peer := d.peers.Peer(blockPack.peerId); peer != nil {
-				// Deliver the received chunk of blocks, and demote in case of errors
-				err := d.queue.Deliver(blockPack.peerId, blockPack.blocks)
+			if peer := d.peers.Peer(bodyPack.peerId); peer != nil {
+				// Deliver the received chunk of bodies, and demote in case of errors
+				err := d.queue.Deliver(bodyPack.peerId, bodyPack.transactions, bodyPack.uncles)
 				switch err {
 				case nil:
 					// If no blocks were delivered, demote the peer (need the delivery above)
-					if len(blockPack.blocks) == 0 {
+					if len(bodyPack.transactions) == 0 || len(bodyPack.uncles) == 0 {
 						peer.Demote()
 						peer.SetIdle()
-						glog.V(logger.Detail).Infof("%s: no blocks delivered", peer)
+						glog.V(logger.Detail).Infof("%s: no block bodies delivered", peer)
 						break
 					}
 					// All was successful, promote the peer and potentially start processing
 					peer.Promote()
 					peer.SetIdle()
-					glog.V(logger.Detail).Infof("%s: delivered %d blocks", peer, len(blockPack.blocks))
+					glog.V(logger.Detail).Infof("%s: delivered %d:%d block bodies", peer, len(bodyPack.transactions), len(bodyPack.uncles))
 					go d.process()
 
 				case errInvalidChain:
 					// The hash chain is invalid (blocks are not ordered properly), abort
 					return err
 
+				case errInvalidBody:
+					// The peer delivered something very bad, drop immediately
+					glog.V(logger.Error).Infof("%s: delivered invalid block, dropping", peer)
+					d.dropPeer(peer.id)
+
 				case errNoFetchesPending:
 					// Peer probably timed out with its delivery but came through
 					// in the end, demote, but allow to to pull from this peer.
@@ -945,18 +1081,18 @@ func (d *Downloader) fetchBlocks(from uint64) error {
 					go d.process()
 				}
 			}
-			// Blocks arrived, try to update the progress
+			// Blocks assembled, try to update the progress
 			select {
 			case update <- struct{}{}:
 			default:
 			}
 
 		case cont := <-d.processCh:
-			// The hash fetcher sent a continuation flag, check if it's done
+			// The header fetcher sent a continuation flag, check if it's done
 			if !cont {
 				finished = true
 			}
-			// Hashes arrive, try to update the progress
+			// Headers arrive, try to update the progress
 			select {
 			case update <- struct{}{}:
 			default:
@@ -974,38 +1110,50 @@ func (d *Downloader) fetchBlocks(from uint64) error {
 			if d.peers.Len() == 0 {
 				return errNoPeers
 			}
-			// Check for block request timeouts and demote the responsible peers
-			for _, pid := range d.queue.Expire(blockHardTTL) {
+			// Check for block body request timeouts and demote the responsible peers
+			for _, pid := range d.queue.Expire(bodyHardTTL) {
 				if peer := d.peers.Peer(pid); peer != nil {
 					peer.Demote()
-					glog.V(logger.Detail).Infof("%s: block delivery timeout", peer)
+					glog.V(logger.Detail).Infof("%s: block body delivery timeout", peer)
 				}
 			}
 			// If there's noting more to fetch, wait or terminate
 			if d.queue.Pending() == 0 {
 				if d.queue.InFlight() == 0 && finished {
-					glog.V(logger.Debug).Infof("Block fetching completed")
+					glog.V(logger.Debug).Infof("Block body fetching completed")
 					return nil
 				}
 				break
 			}
 			// Send a download request to all idle peers, until throttled
+			queuedEmptyBlocks, throttled := false, false
 			for _, peer := range d.peers.IdlePeers() {
 				// Short circuit if throttling activated
 				if d.queue.Throttle() {
+					throttled = true
 					break
 				}
 				// Reserve a chunk of hashes for a peer. A nil can mean either that
 				// no more hashes are available, or that the peer is known not to
 				// have them.
-				request := d.queue.Reserve(peer, peer.Capacity())
+				request, process, err := d.queue.Reserve(peer, peer.Capacity())
+				if err != nil {
+					return err
+				}
+				if process {
+					queuedEmptyBlocks = true
+					go d.process()
+				}
 				if request == nil {
 					continue
 				}
 				if glog.V(logger.Detail) {
-					glog.Infof("%s: requesting %d blocks", peer, len(request.Hashes))
+					glog.Infof("%s: requesting %d block bodies", peer, len(request.Headers))
 				}
 				// Fetch the chunk and make sure any errors return the hashes to the queue
+				if d.bodyFetchHook != nil {
+					d.bodyFetchHook(request.Headers)
+				}
 				if err := peer.Fetch(request); err != nil {
 					glog.V(logger.Error).Infof("%v: fetch failed, rescheduling", peer)
 					d.queue.Cancel(request)
@@ -1013,99 +1161,13 @@ func (d *Downloader) fetchBlocks(from uint64) error {
 			}
 			// Make sure that we have peers available for fetching. If all peers have been tried
 			// and all failed throw an error
-			if !d.queue.Throttle() && d.queue.InFlight() == 0 {
+			if !queuedEmptyBlocks && !throttled && d.queue.InFlight() == 0 {
 				return errPeersUnavailable
 			}
 		}
 	}
 }
 
-// banBlocks retrieves a batch of blocks from a peer feeding us invalid hashes,
-// and bans the head of the retrieved batch.
-//
-// This method only fetches one single batch as the goal is not ban an entire
-// (potentially long) invalid chain - wasting a lot of time in the meanwhile -,
-// but rather to gradually build up a blacklist if the peer keeps reconnecting.
-func (d *Downloader) banBlocks(peerId string, head common.Hash) error {
-	glog.V(logger.Debug).Infof("Banning a batch out of %d blocks from %s", d.queue.Pending(), peerId)
-
-	// Ask the peer being banned for a batch of blocks from the banning point
-	peer := d.peers.Peer(peerId)
-	if peer == nil {
-		return nil
-	}
-	request := d.queue.Reserve(peer, MaxBlockFetch)
-	if request == nil {
-		return nil
-	}
-	if err := peer.Fetch(request); err != nil {
-		return err
-	}
-	// Wait a bit for the reply to arrive, and ban if done so
-	timeout := time.After(blockHardTTL)
-	for {
-		select {
-		case <-d.cancelCh:
-			return errCancelBlockFetch
-
-		case <-timeout:
-			return errTimeout
-
-		case <-d.hashCh:
-			// Out of bounds hashes received, ignore them
-
-		case blockPack := <-d.blockCh:
-			blocks := blockPack.blocks
-
-			// Short circuit if it's a stale cross check
-			if len(blocks) == 1 {
-				block := blocks[0]
-				if _, ok := d.checks[block.Hash()]; ok {
-					delete(d.checks, block.Hash())
-					break
-				}
-			}
-			// Short circuit if it's not from the peer being banned
-			if blockPack.peerId != peerId {
-				break
-			}
-			// Short circuit if no blocks were returned
-			if len(blocks) == 0 {
-				return errors.New("no blocks returned to ban")
-			}
-			// Reconstruct the original chain order and ensure we're banning the correct blocks
-			types.BlockBy(types.Number).Sort(blocks)
-			if bytes.Compare(blocks[0].Hash().Bytes(), head.Bytes()) != 0 {
-				return errors.New("head block not the banned one")
-			}
-			index := 0
-			for _, block := range blocks[1:] {
-				if bytes.Compare(block.ParentHash().Bytes(), blocks[index].Hash().Bytes()) != 0 {
-					break
-				}
-				index++
-			}
-			// Ban the head hash and phase out any excess
-			d.banned.Add(blocks[index].Hash())
-			for d.banned.Size() > maxBannedHashes {
-				var evacuate common.Hash
-
-				d.banned.Each(func(item interface{}) bool {
-					// Skip any hard coded bans
-					if core.BadHashes[item.(common.Hash)] {
-						return true
-					}
-					evacuate = item.(common.Hash)
-					return false
-				})
-				d.banned.Remove(evacuate)
-			}
-			glog.V(logger.Debug).Infof("Banned %d blocks from: %s", index+1, peerId)
-			return nil
-		}
-	}
-}
-
 // process takes blocks from the queue and tries to import them into the chain.
 //
 // The algorithmic flow is as follows:
@@ -1151,6 +1213,9 @@ func (d *Downloader) process() {
 		if len(blocks) == 0 {
 			return
 		}
+		if d.chainInsertHook != nil {
+			d.chainInsertHook(blocks)
+		}
 		// Reset the import statistics
 		d.importLock.Lock()
 		d.importStart = time.Now()
@@ -1184,9 +1249,45 @@ func (d *Downloader) process() {
 	}
 }
 
-// DeliverBlocks injects a new batch of blocks received from a remote node.
+// DeliverHashes61 injects a new batch of hashes received from a remote node into
+// the download schedule. This is usually invoked through the BlockHashesMsg by
+// the protocol handler.
+func (d *Downloader) DeliverHashes61(id string, hashes []common.Hash) (err error) {
+	// Update the delivery metrics for both good and failed deliveries
+	hashInMeter.Mark(int64(len(hashes)))
+	defer func() {
+		if err != nil {
+			hashDropMeter.Mark(int64(len(hashes)))
+		}
+	}()
+	// Make sure the downloader is active
+	if atomic.LoadInt32(&d.synchronising) == 0 {
+		return errNoSyncActive
+	}
+	// Deliver or abort if the sync is canceled while queuing
+	d.cancelLock.RLock()
+	cancel := d.cancelCh
+	d.cancelLock.RUnlock()
+
+	select {
+	case d.hashCh <- hashPack{id, hashes}:
+		return nil
+
+	case <-cancel:
+		return errNoSyncActive
+	}
+}
+
+// DeliverBlocks61 injects a new batch of blocks received from a remote node.
 // This is usually invoked through the BlocksMsg by the protocol handler.
-func (d *Downloader) DeliverBlocks(id string, blocks []*types.Block) error {
+func (d *Downloader) DeliverBlocks61(id string, blocks []*types.Block) (err error) {
+	// Update the delivery metrics for both good and failed deliveries
+	blockInMeter.Mark(int64(len(blocks)))
+	defer func() {
+		if err != nil {
+			blockDropMeter.Mark(int64(len(blocks)))
+		}
+	}()
 	// Make sure the downloader is active
 	if atomic.LoadInt32(&d.synchronising) == 0 {
 		return errNoSyncActive
@@ -1205,10 +1306,16 @@ func (d *Downloader) DeliverBlocks(id string, blocks []*types.Block) error {
 	}
 }
 
-// DeliverHashes injects a new batch of hashes received from a remote node into
-// the download schedule. This is usually invoked through the BlockHashesMsg by
-// the protocol handler.
-func (d *Downloader) DeliverHashes(id string, hashes []common.Hash) error {
+// DeliverHeaders injects a new batch of blck headers received from a remote
+// node into the download schedule.
+func (d *Downloader) DeliverHeaders(id string, headers []*types.Header) (err error) {
+	// Update the delivery metrics for both good and failed deliveries
+	headerInMeter.Mark(int64(len(headers)))
+	defer func() {
+		if err != nil {
+			headerDropMeter.Mark(int64(len(headers)))
+		}
+	}()
 	// Make sure the downloader is active
 	if atomic.LoadInt32(&d.synchronising) == 0 {
 		return errNoSyncActive
@@ -1219,7 +1326,34 @@ func (d *Downloader) DeliverHashes(id string, hashes []common.Hash) error {
 	d.cancelLock.RUnlock()
 
 	select {
-	case d.hashCh <- hashPack{id, hashes}:
+	case d.headerCh <- headerPack{id, headers}:
+		return nil
+
+	case <-cancel:
+		return errNoSyncActive
+	}
+}
+
+// DeliverBodies injects a new batch of block bodies received from a remote node.
+func (d *Downloader) DeliverBodies(id string, transactions [][]*types.Transaction, uncles [][]*types.Header) (err error) {
+	// Update the delivery metrics for both good and failed deliveries
+	bodyInMeter.Mark(int64(len(transactions)))
+	defer func() {
+		if err != nil {
+			bodyDropMeter.Mark(int64(len(transactions)))
+		}
+	}()
+	// Make sure the downloader is active
+	if atomic.LoadInt32(&d.synchronising) == 0 {
+		return errNoSyncActive
+	}
+	// Deliver or abort if the sync is canceled while queuing
+	d.cancelLock.RLock()
+	cancel := d.cancelCh
+	d.cancelLock.RUnlock()
+
+	select {
+	case d.bodyCh <- bodyPack{id, transactions, uncles}:
 		return nil
 
 	case <-cancel:
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index 61fc7827b..8d009b671 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -17,7 +17,6 @@
 package downloader
 
 import (
-	"crypto/rand"
 	"errors"
 	"fmt"
 	"math/big"
@@ -28,20 +27,39 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/params"
 )
 
 var (
-	testdb, _ = ethdb.NewMemDatabase()
-	genesis   = core.GenesisBlockForTesting(testdb, common.Address{}, big.NewInt(0))
+	testdb, _   = ethdb.NewMemDatabase()
+	testKey, _  = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+	testAddress = crypto.PubkeyToAddress(testKey.PublicKey)
+	genesis     = core.GenesisBlockForTesting(testdb, testAddress, big.NewInt(1000000000))
 )
 
-// makeChain creates a chain of n blocks starting at but not including
-// parent. the returned hash chain is ordered head->parent.
+// makeChain creates a chain of n blocks starting at and including parent.
+// the returned hash chain is ordered head->parent. In addition, every 3rd block
+// contains a transaction and every 5th an uncle to allow testing correct block
+// reassembly.
 func makeChain(n int, seed byte, parent *types.Block) ([]common.Hash, map[common.Hash]*types.Block) {
-	blocks := core.GenerateChain(parent, testdb, n, func(i int, gen *core.BlockGen) {
-		gen.SetCoinbase(common.Address{seed})
+	blocks := core.GenerateChain(parent, testdb, n, func(i int, block *core.BlockGen) {
+		block.SetCoinbase(common.Address{seed})
+
+		// If the block number is multiple of 3, send a bonus transaction to the miner
+		if parent == genesis && i%3 == 0 {
+			tx, err := types.NewTransaction(block.TxNonce(testAddress), common.Address{seed}, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(testKey)
+			if err != nil {
+				panic(err)
+			}
+			block.AddTx(tx)
+		}
+		// If the block number is a multiple of 5, add a bonus uncle to the block
+		if i%5 == 0 {
+			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 1).Hash(), Number: big.NewInt(int64(i - 1))})
+		}
 	})
 	hashes := make([]common.Hash, n+1)
 	hashes[len(hashes)-1] = parent.Hash()
@@ -79,8 +97,6 @@ type downloadTester struct {
 	ownBlocks  map[common.Hash]*types.Block            // Blocks belonging to the tester
 	peerHashes map[string][]common.Hash                // Hash chain belonging to different test peers
 	peerBlocks map[string]map[common.Hash]*types.Block // Blocks belonging to different test peers
-
-	maxHashFetch int // Overrides the maximum number of retrieved hashes
 }
 
 // newTester creates a new downloader test mocker.
@@ -157,7 +173,9 @@ func (dl *downloadTester) newPeer(id string, version int, hashes []common.Hash,
 // specific delay time on processing the network packets sent to it, simulating
 // potentially slow network IO.
 func (dl *downloadTester) newSlowPeer(id string, version int, hashes []common.Hash, blocks map[common.Hash]*types.Block, delay time.Duration) error {
-	err := dl.downloader.RegisterPeer(id, version, hashes[0], dl.peerGetRelHashesFn(id, delay), dl.peerGetAbsHashesFn(id, version, delay), dl.peerGetBlocksFn(id, delay))
+	err := dl.downloader.RegisterPeer(id, version, hashes[0],
+		dl.peerGetRelHashesFn(id, delay), dl.peerGetAbsHashesFn(id, delay), dl.peerGetBlocksFn(id, delay),
+		nil, dl.peerGetAbsHeadersFn(id, delay), dl.peerGetBodiesFn(id, delay))
 	if err == nil {
 		// Assign the owned hashes and blocks to the peer (deep copy)
 		dl.peerHashes[id] = make([]common.Hash, len(hashes))
@@ -185,13 +203,9 @@ func (dl *downloadTester) peerGetRelHashesFn(id string, delay time.Duration) fun
 	return func(head common.Hash) error {
 		time.Sleep(delay)
 
-		limit := MaxHashFetch
-		if dl.maxHashFetch > 0 {
-			limit = dl.maxHashFetch
-		}
 		// Gather the next batch of hashes
 		hashes := dl.peerHashes[id]
-		result := make([]common.Hash, 0, limit)
+		result := make([]common.Hash, 0, MaxHashFetch)
 		for i, hash := range hashes {
 			if hash == head {
 				i++
@@ -205,7 +219,7 @@ func (dl *downloadTester) peerGetRelHashesFn(id string, delay time.Duration) fun
 		// Delay delivery a bit to allow attacks to unfold
 		go func() {
 			time.Sleep(time.Millisecond)
-			dl.downloader.DeliverHashes(id, result)
+			dl.downloader.DeliverHashes61(id, result)
 		}()
 		return nil
 	}
@@ -214,29 +228,20 @@ func (dl *downloadTester) peerGetRelHashesFn(id string, delay time.Duration) fun
 // peerGetAbsHashesFn constructs a GetHashesFromNumber function associated with
 // a particular peer in the download tester. The returned function can be used to
 // retrieve batches of hashes from the particularly requested peer.
-func (dl *downloadTester) peerGetAbsHashesFn(id string, version int, delay time.Duration) func(uint64, int) error {
-	// If the simulated peer runs eth/60, this message is not supported
-	if version == eth60 {
-		return func(uint64, int) error { return nil }
-	}
-	// Otherwise create a method to request the blocks by number
+func (dl *downloadTester) peerGetAbsHashesFn(id string, delay time.Duration) func(uint64, int) error {
 	return func(head uint64, count int) error {
 		time.Sleep(delay)
 
-		limit := count
-		if dl.maxHashFetch > 0 {
-			limit = dl.maxHashFetch
-		}
 		// Gather the next batch of hashes
 		hashes := dl.peerHashes[id]
-		result := make([]common.Hash, 0, limit)
-		for i := 0; i < limit && len(hashes)-int(head)-1-i >= 0; i++ {
+		result := make([]common.Hash, 0, count)
+		for i := 0; i < count && len(hashes)-int(head)-1-i >= 0; i++ {
 			result = append(result, hashes[len(hashes)-int(head)-1-i])
 		}
 		// Delay delivery a bit to allow attacks to unfold
 		go func() {
 			time.Sleep(time.Millisecond)
-			dl.downloader.DeliverHashes(id, result)
+			dl.downloader.DeliverHashes61(id, result)
 		}()
 		return nil
 	}
@@ -255,40 +260,75 @@ func (dl *downloadTester) peerGetBlocksFn(id string, delay time.Duration) func([
 				result = append(result, block)
 			}
 		}
-		go dl.downloader.DeliverBlocks(id, result)
+		go dl.downloader.DeliverBlocks61(id, result)
 
 		return nil
 	}
 }
 
-// Tests that simple synchronization, without throttling from a good peer works.
-func TestSynchronisation60(t *testing.T) {
-	// Create a small enough block chain to download and the tester
-	targetBlocks := blockCacheLimit - 15
-	hashes, blocks := makeChain(targetBlocks, 0, genesis)
-
-	tester := newTester()
-	tester.newPeer("peer", eth60, hashes, blocks)
+// peerGetAbsHeadersFn constructs a GetBlockHeaders function based on a numbered
+// origin; associated with a particular peer in the download tester. The returned
+// function can be used to retrieve batches of headers from the particular peer.
+func (dl *downloadTester) peerGetAbsHeadersFn(id string, delay time.Duration) func(uint64, int, int, bool) error {
+	return func(origin uint64, amount int, skip int, reverse bool) error {
+		time.Sleep(delay)
 
-	// Synchronise with the peer and make sure all blocks were retrieved
-	if err := tester.sync("peer", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
+		// Gather the next batch of hashes
+		hashes := dl.peerHashes[id]
+		blocks := dl.peerBlocks[id]
+		result := make([]*types.Header, 0, amount)
+		for i := 0; i < amount && len(hashes)-int(origin)-1-i >= 0; i++ {
+			if block, ok := blocks[hashes[len(hashes)-int(origin)-1-i]]; ok {
+				result = append(result, block.Header())
+			}
+		}
+		// Delay delivery a bit to allow attacks to unfold
+		go func() {
+			time.Sleep(time.Millisecond)
+			dl.downloader.DeliverHeaders(id, result)
+		}()
+		return nil
 	}
-	if imported := len(tester.ownBlocks); imported != targetBlocks+1 {
-		t.Fatalf("synchronised block mismatch: have %v, want %v", imported, targetBlocks+1)
+}
+
+// peerGetBodiesFn constructs a getBlockBodies method associated with a particular
+// peer in the download tester. The returned function can be used to retrieve
+// batches of block bodies from the particularly requested peer.
+func (dl *downloadTester) peerGetBodiesFn(id string, delay time.Duration) func([]common.Hash) error {
+	return func(hashes []common.Hash) error {
+		time.Sleep(delay)
+		blocks := dl.peerBlocks[id]
+
+		transactions := make([][]*types.Transaction, 0, len(hashes))
+		uncles := make([][]*types.Header, 0, len(hashes))
+
+		for _, hash := range hashes {
+			if block, ok := blocks[hash]; ok {
+				transactions = append(transactions, block.Transactions())
+				uncles = append(uncles, block.Uncles())
+			}
+		}
+		go dl.downloader.DeliverBodies(id, transactions, uncles)
+
+		return nil
 	}
 }
 
 // Tests that simple synchronization against a canonical chain works correctly.
 // In this test common ancestor lookup should be short circuited and not require
 // binary searching.
-func TestCanonicalSynchronisation61(t *testing.T) {
+func TestCanonicalSynchronisation61(t *testing.T) { testCanonicalSynchronisation(t, 61) }
+func TestCanonicalSynchronisation62(t *testing.T) { testCanonicalSynchronisation(t, 62) }
+func TestCanonicalSynchronisation63(t *testing.T) { testCanonicalSynchronisation(t, 63) }
+func TestCanonicalSynchronisation64(t *testing.T) { testCanonicalSynchronisation(t, 64) }
+
+func testCanonicalSynchronisation(t *testing.T, protocol int) {
 	// Create a small enough block chain to download
 	targetBlocks := blockCacheLimit - 15
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
 	tester := newTester()
-	tester.newPeer("peer", eth61, hashes, blocks)
+	tester.newPeer("peer", protocol, hashes, blocks)
 
 	// Synchronise with the peer and make sure all blocks were retrieved
 	if err := tester.sync("peer", nil); err != nil {
@@ -301,8 +341,10 @@ func TestCanonicalSynchronisation61(t *testing.T) {
 
 // Tests that if a large batch of blocks are being downloaded, it is throttled
 // until the cached blocks are retrieved.
-func TestThrottling60(t *testing.T) { testThrottling(t, eth60) }
-func TestThrottling61(t *testing.T) { testThrottling(t, eth61) }
+func TestThrottling61(t *testing.T) { testThrottling(t, 61) }
+func TestThrottling62(t *testing.T) { testThrottling(t, 62) }
+func TestThrottling63(t *testing.T) { testThrottling(t, 63) }
+func TestThrottling64(t *testing.T) { testThrottling(t, 64) }
 
 func testThrottling(t *testing.T, protocol int) {
 	// Create a long block chain to download and the tester
@@ -313,11 +355,10 @@ func testThrottling(t *testing.T, protocol int) {
 	tester.newPeer("peer", protocol, hashes, blocks)
 
 	// Wrap the importer to allow stepping
-	done := make(chan int)
-	tester.downloader.insertChain = func(blocks types.Blocks) (int, error) {
-		n, err := tester.insertChain(blocks)
-		done <- n
-		return n, err
+	blocked, proceed := uint32(0), make(chan struct{})
+	tester.downloader.chainInsertHook = func(blocks []*Block) {
+		atomic.StoreUint32(&blocked, uint32(len(blocks)))
+		<-proceed
 	}
 	// Start a synchronisation concurrently
 	errc := make(chan error)
@@ -328,27 +369,25 @@ func testThrottling(t *testing.T, protocol int) {
 	for len(tester.ownBlocks) < targetBlocks+1 {
 		// Wait a bit for sync to throttle itself
 		var cached int
-		for start := time.Now(); time.Since(start) < 3*time.Second; {
+		for start := time.Now(); time.Since(start) < time.Second; {
 			time.Sleep(25 * time.Millisecond)
 
 			cached = len(tester.downloader.queue.blockPool)
-			if cached == blockCacheLimit || len(tester.ownBlocks)+cached == targetBlocks+1 {
+			if cached == blockCacheLimit || len(tester.ownBlocks)+cached+int(atomic.LoadUint32(&blocked)) == targetBlocks+1 {
 				break
 			}
 		}
 		// Make sure we filled up the cache, then exhaust it
 		time.Sleep(25 * time.Millisecond) // give it a chance to screw up
-		if cached != blockCacheLimit && len(tester.ownBlocks)+cached < targetBlocks+1 {
-			t.Fatalf("block count mismatch: have %v, want %v", cached, blockCacheLimit)
+		if cached != blockCacheLimit && len(tester.ownBlocks)+cached+int(atomic.LoadUint32(&blocked)) != targetBlocks+1 {
+			t.Fatalf("block count mismatch: have %v, want %v (owned %v, target %v)", cached, blockCacheLimit, len(tester.ownBlocks), targetBlocks+1)
 		}
-		<-done // finish previous blocking import
-		for cached > maxBlockProcess {
-			cached -= <-done
+		// Permit the blocked blocks to import
+		if atomic.LoadUint32(&blocked) > 0 {
+			atomic.StoreUint32(&blocked, uint32(0))
+			proceed <- struct{}{}
 		}
-		time.Sleep(25 * time.Millisecond) // yield to the insertion
 	}
-	<-done // finish the last blocking import
-
 	// Check that we haven't pulled more blocks than available
 	if len(tester.ownBlocks) > targetBlocks+1 {
 		t.Fatalf("target block count mismatch: have %v, want %v", len(tester.ownBlocks), targetBlocks+1)
@@ -361,14 +400,19 @@ func testThrottling(t *testing.T, protocol int) {
 // Tests that simple synchronization against a forked chain works correctly. In
 // this test common ancestor lookup should *not* be short circuited, and a full
 // binary search should be executed.
-func TestForkedSynchronisation61(t *testing.T) {
+func TestForkedSynchronisation61(t *testing.T) { testForkedSynchronisation(t, 61) }
+func TestForkedSynchronisation62(t *testing.T) { testForkedSynchronisation(t, 62) }
+func TestForkedSynchronisation63(t *testing.T) { testForkedSynchronisation(t, 63) }
+func TestForkedSynchronisation64(t *testing.T) { testForkedSynchronisation(t, 64) }
+
+func testForkedSynchronisation(t *testing.T, protocol int) {
 	// Create a long enough forked chain
 	common, fork := MaxHashFetch, 2*MaxHashFetch
 	hashesA, hashesB, blocksA, blocksB := makeChainFork(common+fork, fork, genesis)
 
 	tester := newTester()
-	tester.newPeer("fork A", eth61, hashesA, blocksA)
-	tester.newPeer("fork B", eth61, hashesB, blocksB)
+	tester.newPeer("fork A", protocol, hashesA, blocksA)
+	tester.newPeer("fork B", protocol, hashesB, blocksB)
 
 	// Synchronise with the peer and make sure all blocks were retrieved
 	if err := tester.sync("fork A", nil); err != nil {
@@ -387,21 +431,36 @@ func TestForkedSynchronisation61(t *testing.T) {
 }
 
 // Tests that an inactive downloader will not accept incoming hashes and blocks.
-func TestInactiveDownloader(t *testing.T) {
+func TestInactiveDownloader61(t *testing.T) {
 	tester := newTester()
 
 	// Check that neither hashes nor blocks are accepted
-	if err := tester.downloader.DeliverHashes("bad peer", []common.Hash{}); err != errNoSyncActive {
+	if err := tester.downloader.DeliverHashes61("bad peer", []common.Hash{}); err != errNoSyncActive {
 		t.Errorf("error mismatch: have %v, want %v", err, errNoSyncActive)
 	}
-	if err := tester.downloader.DeliverBlocks("bad peer", []*types.Block{}); err != errNoSyncActive {
+	if err := tester.downloader.DeliverBlocks61("bad peer", []*types.Block{}); err != errNoSyncActive {
+		t.Errorf("error mismatch: have %v, want %v", err, errNoSyncActive)
+	}
+}
+
+// Tests that an inactive downloader will not accept incoming block headers and bodies.
+func TestInactiveDownloader62(t *testing.T) {
+	tester := newTester()
+
+	// Check that neither block headers nor bodies are accepted
+	if err := tester.downloader.DeliverHeaders("bad peer", []*types.Header{}); err != errNoSyncActive {
+		t.Errorf("error mismatch: have %v, want %v", err, errNoSyncActive)
+	}
+	if err := tester.downloader.DeliverBodies("bad peer", [][]*types.Transaction{}, [][]*types.Header{}); err != errNoSyncActive {
 		t.Errorf("error mismatch: have %v, want %v", err, errNoSyncActive)
 	}
 }
 
 // Tests that a canceled download wipes all previously accumulated state.
-func TestCancel60(t *testing.T) { testCancel(t, eth60) }
-func TestCancel61(t *testing.T) { testCancel(t, eth61) }
+func TestCancel61(t *testing.T) { testCancel(t, 61) }
+func TestCancel62(t *testing.T) { testCancel(t, 62) }
+func TestCancel63(t *testing.T) { testCancel(t, 63) }
+func TestCancel64(t *testing.T) { testCancel(t, 64) }
 
 func testCancel(t *testing.T, protocol int) {
 	// Create a small enough block chain to download and the tester
@@ -409,6 +468,9 @@ func testCancel(t *testing.T, protocol int) {
 	if targetBlocks >= MaxHashFetch {
 		targetBlocks = MaxHashFetch - 15
 	}
+	if targetBlocks >= MaxHeaderFetch {
+		targetBlocks = MaxHeaderFetch - 15
+	}
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
 	tester := newTester()
@@ -416,28 +478,30 @@ func testCancel(t *testing.T, protocol int) {
 
 	// Make sure canceling works with a pristine downloader
 	tester.downloader.cancel()
-	hashCount, blockCount := tester.downloader.queue.Size()
-	if hashCount > 0 || blockCount > 0 {
-		t.Errorf("block or hash count mismatch: %d hashes, %d blocks, want 0", hashCount, blockCount)
+	downloading, importing := tester.downloader.queue.Size()
+	if downloading > 0 || importing > 0 {
+		t.Errorf("download or import count mismatch: %d downloading, %d importing, want 0", downloading, importing)
 	}
 	// Synchronise with the peer, but cancel afterwards
 	if err := tester.sync("peer", nil); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 	tester.downloader.cancel()
-	hashCount, blockCount = tester.downloader.queue.Size()
-	if hashCount > 0 || blockCount > 0 {
-		t.Errorf("block or hash count mismatch: %d hashes, %d blocks, want 0", hashCount, blockCount)
+	downloading, importing = tester.downloader.queue.Size()
+	if downloading > 0 || importing > 0 {
+		t.Errorf("download or import count mismatch: %d downloading, %d importing, want 0", downloading, importing)
 	}
 }
 
 // Tests that synchronisation from multiple peers works as intended (multi thread sanity test).
-func TestMultiSynchronisation60(t *testing.T) { testMultiSynchronisation(t, eth60) }
-func TestMultiSynchronisation61(t *testing.T) { testMultiSynchronisation(t, eth61) }
+func TestMultiSynchronisation61(t *testing.T) { testMultiSynchronisation(t, 61) }
+func TestMultiSynchronisation62(t *testing.T) { testMultiSynchronisation(t, 62) }
+func TestMultiSynchronisation63(t *testing.T) { testMultiSynchronisation(t, 63) }
+func TestMultiSynchronisation64(t *testing.T) { testMultiSynchronisation(t, 64) }
 
 func testMultiSynchronisation(t *testing.T, protocol int) {
 	// Create various peers with various parts of the chain
-	targetPeers := 16
+	targetPeers := 8
 	targetBlocks := targetPeers*blockCacheLimit - 15
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
@@ -463,394 +527,130 @@ func testMultiSynchronisation(t *testing.T, protocol int) {
 	}
 }
 
-// Tests that synchronising with a peer who's very slow at network IO does not
-// stall the other peers in the system.
-func TestSlowSynchronisation60(t *testing.T) {
-	tester := newTester()
+// Tests that if a block is empty (i.e. header only), no body request should be
+// made, and instead the header should be assembled into a whole block in itself.
+func TestEmptyBlockShortCircuit62(t *testing.T) { testEmptyBlockShortCircuit(t, 62) }
+func TestEmptyBlockShortCircuit63(t *testing.T) { testEmptyBlockShortCircuit(t, 63) }
+func TestEmptyBlockShortCircuit64(t *testing.T) { testEmptyBlockShortCircuit(t, 64) }
 
-	// Create a batch of blocks, with a slow and a full speed peer
-	targetCycles := 2
-	targetBlocks := targetCycles*blockCacheLimit - 15
-	targetIODelay := time.Second
+func testEmptyBlockShortCircuit(t *testing.T, protocol int) {
+	// Create a small enough block chain to download
+	targetBlocks := blockCacheLimit - 15
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
-	tester.newSlowPeer("fast", eth60, hashes, blocks, 0)
-	tester.newSlowPeer("slow", eth60, hashes, blocks, targetIODelay)
-
-	// Try to sync with the peers (pull hashes from fast)
-	start := time.Now()
-	if err := tester.sync("fast", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-	if imported := len(tester.ownBlocks); imported != targetBlocks+1 {
-		t.Fatalf("synchronised block mismatch: have %v, want %v", imported, targetBlocks+1)
-	}
-	// Check that the slow peer got hit at most once per block-cache-size import
-	limit := time.Duration(targetCycles+1) * targetIODelay
-	if delay := time.Since(start); delay >= limit {
-		t.Fatalf("synchronisation exceeded delay limit: have %v, want %v", delay, limit)
-	}
-}
-
-// Tests that if a peer returns an invalid chain with a block pointing to a non-
-// existing parent, it is correctly detected and handled.
-func TestNonExistingParentAttack60(t *testing.T) {
 	tester := newTester()
+	tester.newPeer("peer", protocol, hashes, blocks)
 
-	// Forge a single-link chain with a forged header
-	hashes, blocks := makeChain(1, 0, genesis)
-	tester.newPeer("valid", eth60, hashes, blocks)
-
-	wrongblock := types.NewBlock(&types.Header{}, nil, nil, nil)
-	wrongblock.Td = blocks[hashes[0]].Td
-	hashes, blocks = makeChain(1, 0, wrongblock)
-	tester.newPeer("attack", eth60, hashes, blocks)
-
-	// Try and sync with the malicious node and check that it fails
-	if err := tester.sync("attack", nil); err == nil {
-		t.Fatalf("block synchronization succeeded")
-	}
-	if tester.hasBlock(hashes[0]) {
-		t.Fatalf("tester accepted unknown-parent block: %v", blocks[hashes[0]])
+	// Instrument the downloader to signal body requests
+	requested := int32(0)
+	tester.downloader.bodyFetchHook = func(headers []*types.Header) {
+		atomic.AddInt32(&requested, int32(len(headers)))
 	}
-	// Try to synchronize with the valid chain and make sure it succeeds
-	if err := tester.sync("valid", nil); err != nil {
+	// Synchronise with the peer and make sure all blocks were retrieved
+	if err := tester.sync("peer", nil); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
-	if !tester.hasBlock(tester.peerHashes["valid"][0]) {
-		t.Fatalf("tester didn't accept known-parent block: %v", tester.peerBlocks["valid"][hashes[0]])
+	if imported := len(tester.ownBlocks); imported != targetBlocks+1 {
+		t.Fatalf("synchronised block mismatch: have %v, want %v", imported, targetBlocks+1)
 	}
-}
-
-// Tests that if a malicious peers keeps sending us repeating hashes, we don't
-// loop indefinitely.
-func TestRepeatingHashAttack60(t *testing.T) { // TODO: Is this thing valid??
-	tester := newTester()
-
-	// Create a valid chain, but drop the last link
-	hashes, blocks := makeChain(blockCacheLimit, 0, genesis)
-	tester.newPeer("valid", eth60, hashes, blocks)
-	tester.newPeer("attack", eth60, hashes[:len(hashes)-1], blocks)
-
-	// Try and sync with the malicious node
-	errc := make(chan error)
-	go func() {
-		errc <- tester.sync("attack", nil)
-	}()
-	// Make sure that syncing returns and does so with a failure
-	select {
-	case <-time.After(time.Second):
-		t.Fatalf("synchronisation blocked")
-	case err := <-errc:
-		if err == nil {
-			t.Fatalf("synchronisation succeeded")
+	// Validate the number of block bodies that should have been requested
+	needed := 0
+	for _, block := range blocks {
+		if block != genesis && (len(block.Transactions()) > 0 || len(block.Uncles()) > 0) {
+			needed++
 		}
 	}
-	// Ensure that a valid chain can still pass sync
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
+	if int(requested) != needed {
+		t.Fatalf("block body retrieval count mismatch: have %v, want %v", requested, needed)
 	}
 }
 
-// Tests that if a malicious peers returns a non-existent block hash, it should
-// eventually time out and the sync reattempted.
-func TestNonExistingBlockAttack60(t *testing.T) {
-	tester := newTester()
+// Tests that if a peer sends an invalid body for a requested block, it gets
+// dropped immediately by the downloader.
+func TestInvalidBlockBodyAttack62(t *testing.T) { testInvalidBlockBodyAttack(t, 62) }
+func TestInvalidBlockBodyAttack63(t *testing.T) { testInvalidBlockBodyAttack(t, 63) }
+func TestInvalidBlockBodyAttack64(t *testing.T) { testInvalidBlockBodyAttack(t, 64) }
 
-	// Create a valid chain, but forge the last link
-	hashes, blocks := makeChain(blockCacheLimit, 0, genesis)
-	tester.newPeer("valid", eth60, hashes, blocks)
+func testInvalidBlockBodyAttack(t *testing.T, protocol int) {
+	// Create two peers, one feeding invalid block bodies
+	targetBlocks := 4*blockCacheLimit - 15
+	hashes, validBlocks := makeChain(targetBlocks, 0, genesis)
 
-	hashes[len(hashes)/2] = common.Hash{}
-	tester.newPeer("attack", eth60, hashes, blocks)
-
-	// Try and sync with the malicious node and check that it fails
-	if err := tester.sync("attack", nil); err != errPeersUnavailable {
-		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errPeersUnavailable)
-	}
-	// Ensure that a valid chain can still pass sync
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-}
-
-// Tests that if a malicious peer is returning hashes in a weird order, that the
-// sync throttler doesn't choke on them waiting for the valid blocks.
-func TestInvalidHashOrderAttack60(t *testing.T) {
-	tester := newTester()
-
-	// Create a valid long chain, but reverse some hashes within
-	hashes, blocks := makeChain(4*blockCacheLimit, 0, genesis)
-	tester.newPeer("valid", eth60, hashes, blocks)
-
-	chunk1 := make([]common.Hash, blockCacheLimit)
-	chunk2 := make([]common.Hash, blockCacheLimit)
-	copy(chunk1, hashes[blockCacheLimit:2*blockCacheLimit])
-	copy(chunk2, hashes[2*blockCacheLimit:3*blockCacheLimit])
-
-	copy(hashes[2*blockCacheLimit:], chunk1)
-	copy(hashes[blockCacheLimit:], chunk2)
-	tester.newPeer("attack", eth60, hashes, blocks)
-
-	// Try and sync with the malicious node and check that it fails
-	if err := tester.sync("attack", nil); err != errInvalidChain {
-		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
-	}
-	// Ensure that a valid chain can still pass sync
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-}
-
-// Tests that if a malicious peer makes up a random hash chain and tries to push
-// indefinitely, it actually gets caught with it.
-func TestMadeupHashChainAttack60(t *testing.T) {
-	tester := newTester()
-	blockSoftTTL = 100 * time.Millisecond
-	crossCheckCycle = 25 * time.Millisecond
-
-	// Create a long chain of hashes without backing blocks
-	hashes, blocks := makeChain(4*blockCacheLimit, 0, genesis)
-
-	randomHashes := make([]common.Hash, 1024*blockCacheLimit)
-	for i := range randomHashes {
-		rand.Read(randomHashes[i][:])
-	}
-
-	tester.newPeer("valid", eth60, hashes, blocks)
-	tester.newPeer("attack", eth60, randomHashes, nil)
-
-	// Try and sync with the malicious node and check that it fails
-	if err := tester.sync("attack", nil); err != errCrossCheckFailed {
-		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
-	}
-	// Ensure that a valid chain can still pass sync
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-}
-
-// Tests that if a malicious peer makes up a random hash chain, and tries to push
-// indefinitely, one hash at a time, it actually gets caught with it. The reason
-// this is separate from the classical made up chain attack is that sending hashes
-// one by one prevents reliable block/parent verification.
-func TestMadeupHashChainDrippingAttack60(t *testing.T) {
-	// Create a random chain of hashes to drip
-	randomHashes := make([]common.Hash, 16*blockCacheLimit)
-	for i := range randomHashes {
-		rand.Read(randomHashes[i][:])
-	}
-	randomHashes[len(randomHashes)-1] = genesis.Hash()
-	tester := newTester()
-
-	// Try and sync with the attacker, one hash at a time
-	tester.maxHashFetch = 1
-	tester.newPeer("attack", eth60, randomHashes, nil)
-	if err := tester.sync("attack", nil); err != errStallingPeer {
-		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errStallingPeer)
-	}
-}
-
-// Tests that if a malicious peer makes up a random block chain, and tried to
-// push indefinitely, it actually gets caught with it.
-func TestMadeupBlockChainAttack60(t *testing.T) {
-	defaultBlockTTL := blockSoftTTL
-	defaultCrossCheckCycle := crossCheckCycle
-
-	blockSoftTTL = 100 * time.Millisecond
-	crossCheckCycle = 25 * time.Millisecond
-
-	// Create a long chain of blocks and simulate an invalid chain by dropping every second
-	hashes, blocks := makeChain(16*blockCacheLimit, 0, genesis)
-	gapped := make([]common.Hash, len(hashes)/2)
-	for i := 0; i < len(gapped); i++ {
-		gapped[i] = hashes[2*i]
-	}
-	// Try and sync with the malicious node and check that it fails
-	tester := newTester()
-	tester.newPeer("attack", eth60, gapped, blocks)
-	if err := tester.sync("attack", nil); err != errCrossCheckFailed {
-		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
-	}
-	// Ensure that a valid chain can still pass sync
-	blockSoftTTL = defaultBlockTTL
-	crossCheckCycle = defaultCrossCheckCycle
-
-	tester.newPeer("valid", eth60, hashes, blocks)
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-}
-
-// Tests that if one/multiple malicious peers try to feed a banned blockchain to
-// the downloader, it will not keep refetching the same chain indefinitely, but
-// gradually block pieces of it, until its head is also blocked.
-func TestBannedChainStarvationAttack60(t *testing.T) {
-	n := 8 * blockCacheLimit
-	fork := n/2 - 23
-	hashes, forkHashes, blocks, forkBlocks := makeChainFork(n, fork, genesis)
-
-	// Create the tester and ban the selected hash.
-	tester := newTester()
-	tester.downloader.banned.Add(forkHashes[fork-1])
-	tester.newPeer("valid", eth60, hashes, blocks)
-	tester.newPeer("attack", eth60, forkHashes, forkBlocks)
-
-	// Iteratively try to sync, and verify that the banned hash list grows until
-	// the head of the invalid chain is blocked too.
-	for banned := tester.downloader.banned.Size(); ; {
-		// Try to sync with the attacker, check hash chain failure
-		if err := tester.sync("attack", nil); err != errInvalidChain {
-			if tester.downloader.banned.Has(forkHashes[0]) && err == errBannedHead {
-				break
-			}
-			t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
-		}
-		// Check that the ban list grew with at least 1 new item, or all banned
-		bans := tester.downloader.banned.Size()
-		if bans < banned+1 {
-			t.Fatalf("ban count mismatch: have %v, want %v+", bans, banned+1)
-		}
-		banned = bans
-	}
-	// Check that after banning an entire chain, bad peers get dropped
-	if err := tester.newPeer("new attacker", eth60, forkHashes, forkBlocks); err != errBannedHead {
-		t.Fatalf("peer registration mismatch: have %v, want %v", err, errBannedHead)
+	invalidBlocks := make(map[common.Hash]*types.Block)
+	for hash, block := range validBlocks {
+		invalidBlocks[hash] = types.NewBlockWithHeader(block.Header())
 	}
-	if peer := tester.downloader.peers.Peer("new attacker"); peer != nil {
-		t.Fatalf("banned attacker registered: %v", peer)
-	}
-	// Ensure that a valid chain can still pass sync
-	if err := tester.sync("valid", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-}
-
-// Tests that if a peer sends excessively many/large invalid chains that are
-// gradually banned, it will have an upper limit on the consumed memory and also
-// the origin bad hashes will not be evacuated.
-func TestBannedChainMemoryExhaustionAttack60(t *testing.T) {
-	// Construct a banned chain with more chunks than the ban limit
-	n := 8 * blockCacheLimit
-	fork := n/2 - 23
-	hashes, forkHashes, blocks, forkBlocks := makeChainFork(n, fork, genesis)
 
-	// Create the tester and ban the root hash of the fork.
 	tester := newTester()
-	tester.downloader.banned.Add(forkHashes[fork-1])
-
-	// Reduce the test size a bit
-	defaultMaxBlockFetch := MaxBlockFetch
-	defaultMaxBannedHashes := maxBannedHashes
-
-	MaxBlockFetch = 4
-	maxBannedHashes = 256
-
-	tester.newPeer("valid", eth60, hashes, blocks)
-	tester.newPeer("attack", eth60, forkHashes, forkBlocks)
-
-	// Iteratively try to sync, and verify that the banned hash list grows until
-	// the head of the invalid chain is blocked too.
-	for {
-		// Try to sync with the attacker, check hash chain failure
-		if err := tester.sync("attack", nil); err != errInvalidChain {
-			t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
-		}
-		// Short circuit if the entire chain was banned.
-		if tester.downloader.banned.Has(forkHashes[0]) {
-			break
-		}
-		// Otherwise ensure we never exceed the memory allowance and the hard coded bans are untouched
-		if bans := tester.downloader.banned.Size(); bans > maxBannedHashes {
-			t.Fatalf("ban cap exceeded: have %v, want max %v", bans, maxBannedHashes)
-		}
-		for hash := range core.BadHashes {
-			if !tester.downloader.banned.Has(hash) {
-				t.Fatalf("hard coded ban evacuated: %x", hash)
-			}
-		}
-	}
-	// Ensure that a valid chain can still pass sync
-	MaxBlockFetch = defaultMaxBlockFetch
-	maxBannedHashes = defaultMaxBannedHashes
+	tester.newPeer("valid", protocol, hashes, validBlocks)
+	tester.newPeer("attack", protocol, hashes, invalidBlocks)
 
+	// Synchronise with the valid peer (will pull contents from the attacker too)
 	if err := tester.sync("valid", nil); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
-}
-
-// Tests a corner case (potential attack) where a peer delivers both good as well
-// as unrequested blocks to a hash request. This may trigger a different code
-// path than the fully correct or fully invalid delivery, potentially causing
-// internal state problems
-//
-// No, don't delete this test, it actually did happen!
-func TestOverlappingDeliveryAttack60(t *testing.T) {
-	// Create an arbitrary batch of blocks ( < cache-size not to block)
-	targetBlocks := blockCacheLimit - 23
-	hashes, blocks := makeChain(targetBlocks, 0, genesis)
-
-	// Register an attacker that always returns non-requested blocks too
-	tester := newTester()
-	tester.newPeer("attack", eth60, hashes, blocks)
-
-	rawGetBlocks := tester.downloader.peers.Peer("attack").getBlocks
-	tester.downloader.peers.Peer("attack").getBlocks = func(request []common.Hash) error {
-		// Add a non requested hash the screw the delivery (genesis should be fine)
-		return rawGetBlocks(append(request, hashes[0]))
-	}
-	// Test that synchronisation can complete, check for import success
-	if err := tester.sync("attack", nil); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
+	if imported := len(tester.ownBlocks); imported != len(hashes) {
+		t.Fatalf("synchronised block mismatch: have %v, want %v", imported, len(hashes))
 	}
-	start := time.Now()
-	for len(tester.ownHashes) != len(hashes) && time.Since(start) < time.Second {
-		time.Sleep(50 * time.Millisecond)
-	}
-	if len(tester.ownHashes) != len(hashes) {
-		t.Fatalf("chain length mismatch: have %v, want %v", len(tester.ownHashes), len(hashes))
+	// Make sure the attacker was detected and dropped in the mean time
+	if _, ok := tester.peerHashes["attack"]; ok {
+		t.Fatalf("block body attacker not detected/dropped")
 	}
 }
 
 // Tests that a peer advertising an high TD doesn't get to stall the downloader
 // afterwards by not sending any useful hashes.
-func TestHighTDStarvationAttack61(t *testing.T) {
+func TestHighTDStarvationAttack61(t *testing.T) { testHighTDStarvationAttack(t, 61) }
+func TestHighTDStarvationAttack62(t *testing.T) { testHighTDStarvationAttack(t, 62) }
+func TestHighTDStarvationAttack63(t *testing.T) { testHighTDStarvationAttack(t, 63) }
+func TestHighTDStarvationAttack64(t *testing.T) { testHighTDStarvationAttack(t, 64) }
+
+func testHighTDStarvationAttack(t *testing.T, protocol int) {
 	tester := newTester()
-	tester.newPeer("attack", eth61, []common.Hash{genesis.Hash()}, nil)
+	hashes, blocks := makeChain(0, 0, genesis)
+
+	tester.newPeer("attack", protocol, []common.Hash{hashes[0]}, blocks)
 	if err := tester.sync("attack", big.NewInt(1000000)); err != errStallingPeer {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errStallingPeer)
 	}
 }
 
 // Tests that misbehaving peers are disconnected, whilst behaving ones are not.
-func TestHashAttackerDropping(t *testing.T) {
+func TestBlockHeaderAttackerDropping61(t *testing.T) { testBlockHeaderAttackerDropping(t, 61) }
+func TestBlockHeaderAttackerDropping62(t *testing.T) { testBlockHeaderAttackerDropping(t, 62) }
+func TestBlockHeaderAttackerDropping63(t *testing.T) { testBlockHeaderAttackerDropping(t, 63) }
+func TestBlockHeaderAttackerDropping64(t *testing.T) { testBlockHeaderAttackerDropping(t, 64) }
+
+func testBlockHeaderAttackerDropping(t *testing.T, protocol int) {
 	// Define the disconnection requirement for individual hash fetch errors
 	tests := []struct {
 		result error
 		drop   bool
 	}{
-		{nil, false},                 // Sync succeeded, all is well
-		{errBusy, false},             // Sync is already in progress, no problem
-		{errUnknownPeer, false},      // Peer is unknown, was already dropped, don't double drop
-		{errBadPeer, true},           // Peer was deemed bad for some reason, drop it
-		{errStallingPeer, true},      // Peer was detected to be stalling, drop it
-		{errBannedHead, true},        // Peer's head hash is a known bad hash, drop it
-		{errNoPeers, false},          // No peers to download from, soft race, no issue
-		{errPendingQueue, false},     // There are blocks still cached, wait to exhaust, no issue
-		{errTimeout, true},           // No hashes received in due time, drop the peer
-		{errEmptyHashSet, true},      // No hashes were returned as a response, drop as it's a dead end
-		{errPeersUnavailable, true},  // Nobody had the advertised blocks, drop the advertiser
-		{errInvalidChain, true},      // Hash chain was detected as invalid, definitely drop
-		{errCrossCheckFailed, true},  // Hash-origin failed to pass a block cross check, drop
-		{errCancelHashFetch, false},  // Synchronisation was canceled, origin may be innocent, don't drop
-		{errCancelBlockFetch, false}, // Synchronisation was canceled, origin may be innocent, don't drop
+		{nil, false},                  // Sync succeeded, all is well
+		{errBusy, false},              // Sync is already in progress, no problem
+		{errUnknownPeer, false},       // Peer is unknown, was already dropped, don't double drop
+		{errBadPeer, true},            // Peer was deemed bad for some reason, drop it
+		{errStallingPeer, true},       // Peer was detected to be stalling, drop it
+		{errNoPeers, false},           // No peers to download from, soft race, no issue
+		{errPendingQueue, false},      // There are blocks still cached, wait to exhaust, no issue
+		{errTimeout, true},            // No hashes received in due time, drop the peer
+		{errEmptyHashSet, true},       // No hashes were returned as a response, drop as it's a dead end
+		{errEmptyHeaderSet, true},     // No headers were returned as a response, drop as it's a dead end
+		{errPeersUnavailable, true},   // Nobody had the advertised blocks, drop the advertiser
+		{errInvalidChain, true},       // Hash chain was detected as invalid, definitely drop
+		{errInvalidBody, false},       // A bad peer was detected, but not the sync origin
+		{errCancelHashFetch, false},   // Synchronisation was canceled, origin may be innocent, don't drop
+		{errCancelBlockFetch, false},  // Synchronisation was canceled, origin may be innocent, don't drop
+		{errCancelHeaderFetch, false}, // Synchronisation was canceled, origin may be innocent, don't drop
+		{errCancelBodyFetch, false},   // Synchronisation was canceled, origin may be innocent, don't drop
 	}
 	// Run the tests and check disconnection status
 	tester := newTester()
 	for i, tt := range tests {
 		// Register a new peer and ensure it's presence
 		id := fmt.Sprintf("test %d", i)
-		if err := tester.newPeer(id, eth60, []common.Hash{genesis.Hash()}, nil); err != nil {
+		if err := tester.newPeer(id, protocol, []common.Hash{genesis.Hash()}, nil); err != nil {
 			t.Fatalf("test %d: failed to register new peer: %v", i, err)
 		}
 		if _, ok := tester.peerHashes[id]; !ok {
@@ -867,7 +667,12 @@ func TestHashAttackerDropping(t *testing.T) {
 }
 
 // Tests that feeding bad blocks will result in a peer drop.
-func TestBlockAttackerDropping(t *testing.T) {
+func TestBlockBodyAttackerDropping61(t *testing.T) { testBlockBodyAttackerDropping(t, 61) }
+func TestBlockBodyAttackerDropping62(t *testing.T) { testBlockBodyAttackerDropping(t, 62) }
+func TestBlockBodyAttackerDropping63(t *testing.T) { testBlockBodyAttackerDropping(t, 63) }
+func TestBlockBodyAttackerDropping64(t *testing.T) { testBlockBodyAttackerDropping(t, 64) }
+
+func testBlockBodyAttackerDropping(t *testing.T, protocol int) {
 	// Define the disconnection requirement for individual block import errors
 	tests := []struct {
 		failure bool
@@ -882,7 +687,7 @@ func TestBlockAttackerDropping(t *testing.T) {
 	for i, tt := range tests {
 		// Register a new peer and ensure it's presence
 		id := fmt.Sprintf("test %d", i)
-		if err := tester.newPeer(id, eth60, []common.Hash{common.Hash{}}, nil); err != nil {
+		if err := tester.newPeer(id, protocol, []common.Hash{common.Hash{}}, nil); err != nil {
 			t.Fatalf("test %d: failed to register new peer: %v", i, err)
 		}
 		if _, ok := tester.peerHashes[id]; !ok {
diff --git a/eth/downloader/metrics.go b/eth/downloader/metrics.go
new file mode 100644
index 000000000..fd926affd
--- /dev/null
+++ b/eth/downloader/metrics.go
@@ -0,0 +1,45 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Contains the metrics collected by the downloader.
+
+package downloader
+
+import (
+	"github.com/ethereum/go-ethereum/metrics"
+)
+
+var (
+	hashInMeter      = metrics.NewMeter("eth/downloader/hashes/in")
+	hashReqTimer     = metrics.NewTimer("eth/downloader/hashes/req")
+	hashDropMeter    = metrics.NewMeter("eth/downloader/hashes/drop")
+	hashTimeoutMeter = metrics.NewMeter("eth/downloader/hashes/timeout")
+
+	blockInMeter      = metrics.NewMeter("eth/downloader/blocks/in")
+	blockReqTimer     = metrics.NewTimer("eth/downloader/blocks/req")
+	blockDropMeter    = metrics.NewMeter("eth/downloader/blocks/drop")
+	blockTimeoutMeter = metrics.NewMeter("eth/downloader/blocks/timeout")
+
+	headerInMeter      = metrics.NewMeter("eth/downloader/headers/in")
+	headerReqTimer     = metrics.NewTimer("eth/downloader/headers/req")
+	headerDropMeter    = metrics.NewMeter("eth/downloader/headers/drop")
+	headerTimeoutMeter = metrics.NewMeter("eth/downloader/headers/timeout")
+
+	bodyInMeter      = metrics.NewMeter("eth/downloader/bodies/in")
+	bodyReqTimer     = metrics.NewTimer("eth/downloader/bodies/req")
+	bodyDropMeter    = metrics.NewMeter("eth/downloader/bodies/drop")
+	bodyTimeoutMeter = metrics.NewMeter("eth/downloader/bodies/timeout")
+)
diff --git a/eth/downloader/peer.go b/eth/downloader/peer.go
index 4273b9168..8fd1f9a99 100644
--- a/eth/downloader/peer.go
+++ b/eth/downloader/peer.go
@@ -31,10 +31,16 @@ import (
 	"gopkg.in/fatih/set.v0"
 )
 
+// Hash and block fetchers belonging to eth/61 and below
 type relativeHashFetcherFn func(common.Hash) error
 type absoluteHashFetcherFn func(uint64, int) error
 type blockFetcherFn func([]common.Hash) error
 
+// Block header and body fethers belonging to eth/62 and above
+type relativeHeaderFetcherFn func(common.Hash, int, int, bool) error
+type absoluteHeaderFetcherFn func(uint64, int, int, bool) error
+type blockBodyFetcherFn func([]common.Hash) error
+
 var (
 	errAlreadyFetching   = errors.New("already fetching blocks from peer")
 	errAlreadyRegistered = errors.New("peer is already registered")
@@ -54,25 +60,37 @@ type peer struct {
 
 	ignored *set.Set // Set of hashes not to request (didn't have previously)
 
-	getRelHashes relativeHashFetcherFn // Method to retrieve a batch of hashes from an origin hash
-	getAbsHashes absoluteHashFetcherFn // Method to retrieve a batch of hashes from an absolute position
-	getBlocks    blockFetcherFn        // Method to retrieve a batch of blocks
+	getRelHashes relativeHashFetcherFn // [eth/61] Method to retrieve a batch of hashes from an origin hash
+	getAbsHashes absoluteHashFetcherFn // [eth/61] Method to retrieve a batch of hashes from an absolute position
+	getBlocks    blockFetcherFn        // [eth/61] Method to retrieve a batch of blocks
+
+	getRelHeaders  relativeHeaderFetcherFn // [eth/62] Method to retrieve a batch of headers from an origin hash
+	getAbsHeaders  absoluteHeaderFetcherFn // [eth/62] Method to retrieve a batch of headers from an absolute position
+	getBlockBodies blockBodyFetcherFn      // [eth/62] Method to retrieve a batch of block bodies
 
 	version int // Eth protocol version number to switch strategies
 }
 
 // newPeer create a new downloader peer, with specific hash and block retrieval
 // mechanisms.
-func newPeer(id string, version int, head common.Hash, getRelHashes relativeHashFetcherFn, getAbsHashes absoluteHashFetcherFn, getBlocks blockFetcherFn) *peer {
+func newPeer(id string, version int, head common.Hash,
+	getRelHashes relativeHashFetcherFn, getAbsHashes absoluteHashFetcherFn, getBlocks blockFetcherFn, // eth/61 callbacks, remove when upgrading
+	getRelHeaders relativeHeaderFetcherFn, getAbsHeaders absoluteHeaderFetcherFn, getBlockBodies blockBodyFetcherFn) *peer {
 	return &peer{
-		id:           id,
-		head:         head,
-		capacity:     1,
+		id:       id,
+		head:     head,
+		capacity: 1,
+		ignored:  set.New(),
+
 		getRelHashes: getRelHashes,
 		getAbsHashes: getAbsHashes,
 		getBlocks:    getBlocks,
-		ignored:      set.New(),
-		version:      version,
+
+		getRelHeaders:  getRelHeaders,
+		getAbsHeaders:  getAbsHeaders,
+		getBlockBodies: getBlockBodies,
+
+		version: version,
 	}
 }
 
@@ -83,8 +101,8 @@ func (p *peer) Reset() {
 	p.ignored.Clear()
 }
 
-// Fetch sends a block retrieval request to the remote peer.
-func (p *peer) Fetch(request *fetchRequest) error {
+// Fetch61 sends a block retrieval request to the remote peer.
+func (p *peer) Fetch61(request *fetchRequest) error {
 	// Short circuit if the peer is already fetching
 	if !atomic.CompareAndSwapInt32(&p.idle, 0, 1) {
 		return errAlreadyFetching
@@ -101,10 +119,28 @@ func (p *peer) Fetch(request *fetchRequest) error {
 	return nil
 }
 
-// SetIdle sets the peer to idle, allowing it to execute new retrieval requests.
+// Fetch sends a block body retrieval request to the remote peer.
+func (p *peer) Fetch(request *fetchRequest) error {
+	// Short circuit if the peer is already fetching
+	if !atomic.CompareAndSwapInt32(&p.idle, 0, 1) {
+		return errAlreadyFetching
+	}
+	p.started = time.Now()
+
+	// Convert the header set to a retrievable slice
+	hashes := make([]common.Hash, 0, len(request.Headers))
+	for _, header := range request.Headers {
+		hashes = append(hashes, header.Hash())
+	}
+	go p.getBlockBodies(hashes)
+
+	return nil
+}
+
+// SetIdle61 sets the peer to idle, allowing it to execute new retrieval requests.
 // Its block retrieval allowance will also be updated either up- or downwards,
 // depending on whether the previous fetch completed in time or not.
-func (p *peer) SetIdle() {
+func (p *peer) SetIdle61() {
 	// Update the peer's download allowance based on previous performance
 	scale := 2.0
 	if time.Since(p.started) > blockSoftTTL {
@@ -131,6 +167,36 @@ func (p *peer) SetIdle() {
 	atomic.StoreInt32(&p.idle, 0)
 }
 
+// SetIdle sets the peer to idle, allowing it to execute new retrieval requests.
+// Its block body retrieval allowance will also be updated either up- or downwards,
+// depending on whether the previous fetch completed in time or not.
+func (p *peer) SetIdle() {
+	// Update the peer's download allowance based on previous performance
+	scale := 2.0
+	if time.Since(p.started) > bodySoftTTL {
+		scale = 0.5
+		if time.Since(p.started) > bodyHardTTL {
+			scale = 1 / float64(MaxBodyFetch) // reduces capacity to 1
+		}
+	}
+	for {
+		// Calculate the new download bandwidth allowance
+		prev := atomic.LoadInt32(&p.capacity)
+		next := int32(math.Max(1, math.Min(float64(MaxBodyFetch), float64(prev)*scale)))
+
+		// Try to update the old value
+		if atomic.CompareAndSwapInt32(&p.capacity, prev, next) {
+			// If we're having problems at 1 capacity, try to find better peers
+			if next == 1 {
+				p.Demote()
+			}
+			break
+		}
+	}
+	// Set the peer to idle to allow further block requests
+	atomic.StoreInt32(&p.idle, 0)
+}
+
 // Capacity retrieves the peers block download allowance based on its previously
 // discovered bandwidth capacity.
 func (p *peer) Capacity() int {
diff --git a/eth/downloader/queue.go b/eth/downloader/queue.go
index 96e08e144..7db78327b 100644
--- a/eth/downloader/queue.go
+++ b/eth/downloader/queue.go
@@ -43,16 +43,20 @@ var (
 
 // fetchRequest is a currently running block retrieval operation.
 type fetchRequest struct {
-	Peer   *peer               // Peer to which the request was sent
-	Hashes map[common.Hash]int // Requested hashes with their insertion index (priority)
-	Time   time.Time           // Time when the request was made
+	Peer    *peer               // Peer to which the request was sent
+	Hashes  map[common.Hash]int // [eth/61] Requested hashes with their insertion index (priority)
+	Headers []*types.Header     // [eth/62] Requested headers, sorted by request order
+	Time    time.Time           // Time when the request was made
 }
 
 // queue represents hashes that are either need fetching or are being fetched
 type queue struct {
-	hashPool    map[common.Hash]int // Pending hashes, mapping to their insertion index (priority)
-	hashQueue   *prque.Prque        // Priority queue of the block hashes to fetch
-	hashCounter int                 // Counter indexing the added hashes to ensure retrieval order
+	hashPool    map[common.Hash]int // [eth/61] Pending hashes, mapping to their insertion index (priority)
+	hashQueue   *prque.Prque        // [eth/61] Priority queue of the block hashes to fetch
+	hashCounter int                 // [eth/61] Counter indexing the added hashes to ensure retrieval order
+
+	headerPool  map[common.Hash]*types.Header // [eth/62] Pending headers, mapping from their hashes
+	headerQueue *prque.Prque                  // [eth/62] Priority queue of the headers to fetch the bodies for
 
 	pendPool map[string]*fetchRequest // Currently pending block retrieval operations
 
@@ -66,11 +70,13 @@ type queue struct {
 // newQueue creates a new download queue for scheduling block retrieval.
 func newQueue() *queue {
 	return &queue{
-		hashPool:   make(map[common.Hash]int),
-		hashQueue:  prque.New(),
-		pendPool:   make(map[string]*fetchRequest),
-		blockPool:  make(map[common.Hash]uint64),
-		blockCache: make([]*Block, blockCacheLimit),
+		hashPool:    make(map[common.Hash]int),
+		hashQueue:   prque.New(),
+		headerPool:  make(map[common.Hash]*types.Header),
+		headerQueue: prque.New(),
+		pendPool:    make(map[string]*fetchRequest),
+		blockPool:   make(map[common.Hash]uint64),
+		blockCache:  make([]*Block, blockCacheLimit),
 	}
 }
 
@@ -83,6 +89,9 @@ func (q *queue) Reset() {
 	q.hashQueue.Reset()
 	q.hashCounter = 0
 
+	q.headerPool = make(map[common.Hash]*types.Header)
+	q.headerQueue.Reset()
+
 	q.pendPool = make(map[string]*fetchRequest)
 
 	q.blockPool = make(map[common.Hash]uint64)
@@ -90,21 +99,21 @@ func (q *queue) Reset() {
 	q.blockCache = make([]*Block, blockCacheLimit)
 }
 
-// Size retrieves the number of hashes in the queue, returning separately for
+// Size retrieves the number of blocks in the queue, returning separately for
 // pending and already downloaded.
 func (q *queue) Size() (int, int) {
 	q.lock.RLock()
 	defer q.lock.RUnlock()
 
-	return len(q.hashPool), len(q.blockPool)
+	return len(q.hashPool) + len(q.headerPool), len(q.blockPool)
 }
 
-// Pending retrieves the number of hashes pending for retrieval.
+// Pending retrieves the number of blocks pending for retrieval.
 func (q *queue) Pending() int {
 	q.lock.RLock()
 	defer q.lock.RUnlock()
 
-	return q.hashQueue.Size()
+	return q.hashQueue.Size() + q.headerQueue.Size()
 }
 
 // InFlight retrieves the number of fetch requests currently in flight.
@@ -124,7 +133,7 @@ func (q *queue) Throttle() bool {
 	// Calculate the currently in-flight block requests
 	pending := 0
 	for _, request := range q.pendPool {
-		pending += len(request.Hashes)
+		pending += len(request.Hashes) + len(request.Headers)
 	}
 	// Throttle if more blocks are in-flight than free space in the cache
 	return pending >= len(q.blockCache)-len(q.blockPool)
@@ -138,15 +147,18 @@ func (q *queue) Has(hash common.Hash) bool {
 	if _, ok := q.hashPool[hash]; ok {
 		return true
 	}
+	if _, ok := q.headerPool[hash]; ok {
+		return true
+	}
 	if _, ok := q.blockPool[hash]; ok {
 		return true
 	}
 	return false
 }
 
-// Insert adds a set of hashes for the download queue for scheduling, returning
+// Insert61 adds a set of hashes for the download queue for scheduling, returning
 // the new hashes encountered.
-func (q *queue) Insert(hashes []common.Hash, fifo bool) []common.Hash {
+func (q *queue) Insert61(hashes []common.Hash, fifo bool) []common.Hash {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
@@ -172,6 +184,29 @@ func (q *queue) Insert(hashes []common.Hash, fifo bool) []common.Hash {
 	return inserts
 }
 
+// Insert adds a set of headers for the download queue for scheduling, returning
+// the new headers encountered.
+func (q *queue) Insert(headers []*types.Header) []*types.Header {
+	q.lock.Lock()
+	defer q.lock.Unlock()
+
+	// Insert all the headers prioritized by the contained block number
+	inserts := make([]*types.Header, 0, len(headers))
+	for _, header := range headers {
+		// Make sure no duplicate requests are executed
+		hash := header.Hash()
+		if _, ok := q.headerPool[hash]; ok {
+			glog.V(logger.Warn).Infof("Header %x already scheduled", hash)
+			continue
+		}
+		// Queue the header for body retrieval
+		inserts = append(inserts, header)
+		q.headerPool[hash] = header
+		q.headerQueue.Push(header, -float32(header.Number.Uint64()))
+	}
+	return inserts
+}
+
 // GetHeadBlock retrieves the first block from the cache, or nil if it hasn't
 // been downloaded yet (or simply non existent).
 func (q *queue) GetHeadBlock() *Block {
@@ -227,9 +262,9 @@ func (q *queue) TakeBlocks() []*Block {
 	return blocks
 }
 
-// Reserve reserves a set of hashes for the given peer, skipping any previously
+// Reserve61 reserves a set of hashes for the given peer, skipping any previously
 // failed download.
-func (q *queue) Reserve(p *peer, count int) *fetchRequest {
+func (q *queue) Reserve61(p *peer, count int) *fetchRequest {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
@@ -276,6 +311,68 @@ func (q *queue) Reserve(p *peer, count int) *fetchRequest {
 	return request
 }
 
+// Reserve reserves a set of headers for the given peer, skipping any previously
+// failed download. Beside the next batch of needed fetches, it also returns a
+// flag whether empty blocks were queued requiring processing.
+func (q *queue) Reserve(p *peer, count int) (*fetchRequest, bool, error) {
+	q.lock.Lock()
+	defer q.lock.Unlock()
+
+	// Short circuit if the pool has been depleted, or if the peer's already
+	// downloading something (sanity check not to corrupt state)
+	if q.headerQueue.Empty() {
+		return nil, false, nil
+	}
+	if _, ok := q.pendPool[p.id]; ok {
+		return nil, false, nil
+	}
+	// Calculate an upper limit on the bodies we might fetch (i.e. throttling)
+	space := len(q.blockCache) - len(q.blockPool)
+	for _, request := range q.pendPool {
+		space -= len(request.Headers)
+	}
+	// Retrieve a batch of headers, skipping previously failed ones
+	send := make([]*types.Header, 0, count)
+	skip := make([]*types.Header, 0)
+
+	process := false
+	for proc := 0; proc < space && len(send) < count && !q.headerQueue.Empty(); proc++ {
+		header := q.headerQueue.PopItem().(*types.Header)
+
+		// If the header defines an empty block, deliver straight
+		if header.TxHash == types.DeriveSha(types.Transactions{}) && header.UncleHash == types.CalcUncleHash([]*types.Header{}) {
+			if err := q.enqueue("", types.NewBlockWithHeader(header)); err != nil {
+				return nil, false, errInvalidChain
+			}
+			delete(q.headerPool, header.Hash())
+			process, space, proc = true, space-1, proc-1
+			continue
+		}
+		// If it's a content block, add to the body fetch request
+		if p.ignored.Has(header.Hash()) {
+			skip = append(skip, header)
+		} else {
+			send = append(send, header)
+		}
+	}
+	// Merge all the skipped headers back
+	for _, header := range skip {
+		q.headerQueue.Push(header, -float32(header.Number.Uint64()))
+	}
+	// Assemble and return the block download request
+	if len(send) == 0 {
+		return nil, process, nil
+	}
+	request := &fetchRequest{
+		Peer:    p,
+		Headers: send,
+		Time:    time.Now(),
+	}
+	q.pendPool[p.id] = request
+
+	return request, process, nil
+}
+
 // Cancel aborts a fetch request, returning all pending hashes to the queue.
 func (q *queue) Cancel(request *fetchRequest) {
 	q.lock.Lock()
@@ -284,6 +381,9 @@ func (q *queue) Cancel(request *fetchRequest) {
 	for hash, index := range request.Hashes {
 		q.hashQueue.Push(hash, float32(index))
 	}
+	for _, header := range request.Headers {
+		q.headerQueue.Push(header, -float32(header.Number.Uint64()))
+	}
 	delete(q.pendPool, request.Peer.id)
 }
 
@@ -297,9 +397,19 @@ func (q *queue) Expire(timeout time.Duration) []string {
 	peers := []string{}
 	for id, request := range q.pendPool {
 		if time.Since(request.Time) > timeout {
+			// Update the metrics with the timeout
+			if len(request.Hashes) > 0 {
+				blockTimeoutMeter.Mark(1)
+			} else {
+				bodyTimeoutMeter.Mark(1)
+			}
+			// Return any non satisfied requests to the pool
 			for hash, index := range request.Hashes {
 				q.hashQueue.Push(hash, float32(index))
 			}
+			for _, header := range request.Headers {
+				q.headerQueue.Push(header, -float32(header.Number.Uint64()))
+			}
 			peers = append(peers, id)
 		}
 	}
@@ -310,8 +420,8 @@ func (q *queue) Expire(timeout time.Duration) []string {
 	return peers
 }
 
-// Deliver injects a block retrieval response into the download queue.
-func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
+// Deliver61 injects a block retrieval response into the download queue.
+func (q *queue) Deliver61(id string, blocks []*types.Block) (err error) {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
@@ -320,6 +430,7 @@ func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
 	if request == nil {
 		return errNoFetchesPending
 	}
+	blockReqTimer.UpdateSince(request.Time)
 	delete(q.pendPool, id)
 
 	// If no blocks were retrieved, mark them as unavailable for the origin peer
@@ -337,19 +448,12 @@ func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
 			errs = append(errs, fmt.Errorf("non-requested block %x", hash))
 			continue
 		}
-		// If a requested block falls out of the range, the hash chain is invalid
-		index := int(int64(block.NumberU64()) - int64(q.blockOffset))
-		if index >= len(q.blockCache) || index < 0 {
-			return errInvalidChain
-		}
-		// Otherwise merge the block and mark the hash block
-		q.blockCache[index] = &Block{
-			RawBlock:   block,
-			OriginPeer: id,
+		// Queue the block up for processing
+		if err := q.enqueue(id, block); err != nil {
+			return err
 		}
 		delete(request.Hashes, hash)
 		delete(q.hashPool, hash)
-		q.blockPool[hash] = block.NumberU64()
 	}
 	// Return all failed or missing fetches to the queue
 	for hash, index := range request.Hashes {
@@ -365,6 +469,89 @@ func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
 	return nil
 }
 
+// Deliver injects a block body retrieval response into the download queue.
+func (q *queue) Deliver(id string, txLists [][]*types.Transaction, uncleLists [][]*types.Header) error {
+	q.lock.Lock()
+	defer q.lock.Unlock()
+
+	// Short circuit if the block bodies were never requested
+	request := q.pendPool[id]
+	if request == nil {
+		return errNoFetchesPending
+	}
+	bodyReqTimer.UpdateSince(request.Time)
+	delete(q.pendPool, id)
+
+	// If no block bodies were retrieved, mark them as unavailable for the origin peer
+	if len(txLists) == 0 || len(uncleLists) == 0 {
+		for hash, _ := range request.Headers {
+			request.Peer.ignored.Add(hash)
+		}
+	}
+	// Assemble each of the block bodies with their headers and queue for processing
+	errs := make([]error, 0)
+	for i, header := range request.Headers {
+		// Short circuit block assembly if no more bodies are found
+		if i >= len(txLists) || i >= len(uncleLists) {
+			break
+		}
+		// Reconstruct the next block if contents match up
+		if types.DeriveSha(types.Transactions(txLists[i])) != header.TxHash || types.CalcUncleHash(uncleLists[i]) != header.UncleHash {
+			errs = []error{errInvalidBody}
+			break
+		}
+		block := types.NewBlockWithHeader(header).WithBody(txLists[i], uncleLists[i])
+
+		// Queue the block up for processing
+		if err := q.enqueue(id, block); err != nil {
+			errs = []error{err}
+			break
+		}
+		request.Headers[i] = nil
+		delete(q.headerPool, header.Hash())
+	}
+	// Return all failed or missing fetches to the queue
+	for _, header := range request.Headers {
+		if header != nil {
+			q.headerQueue.Push(header, -float32(header.Number.Uint64()))
+		}
+	}
+	// If none of the blocks were good, it's a stale delivery
+	switch {
+	case len(errs) == 0:
+		return nil
+
+	case len(errs) == 1 && errs[0] == errInvalidBody:
+		return errInvalidBody
+
+	case len(errs) == 1 && errs[0] == errInvalidChain:
+		return errInvalidChain
+
+	case len(errs) == len(request.Headers):
+		return errStaleDelivery
+
+	default:
+		return fmt.Errorf("multiple failures: %v", errs)
+	}
+}
+
+// enqueue inserts a new block into the final delivery queue, waiting for pickup
+// by the processor.
+func (q *queue) enqueue(origin string, block *types.Block) error {
+	// If a requested block falls out of the range, the hash chain is invalid
+	index := int(int64(block.NumberU64()) - int64(q.blockOffset))
+	if index >= len(q.blockCache) || index < 0 {
+		return errInvalidChain
+	}
+	// Otherwise merge the block and mark the hash done
+	q.blockCache[index] = &Block{
+		RawBlock:   block,
+		OriginPeer: origin,
+	}
+	q.blockPool[block.Header().Hash()] = block.NumberU64()
+	return nil
+}
+
 // Prepare configures the block cache offset to allow accepting inbound blocks.
 func (q *queue) Prepare(offset uint64) {
 	q.lock.Lock()
diff --git a/eth/fetcher/fetcher.go b/eth/fetcher/fetcher.go
index 55b6c5c1c..b8ec1fc55 100644
--- a/eth/fetcher/fetcher.go
+++ b/eth/fetcher/fetcher.go
@@ -51,6 +51,12 @@ type blockRetrievalFn func(common.Hash) *types.Block
 // blockRequesterFn is a callback type for sending a block retrieval request.
 type blockRequesterFn func([]common.Hash) error
 
+// headerRequesterFn is a callback type for sending a header retrieval request.
+type headerRequesterFn func(common.Hash) error
+
+// bodyRequesterFn is a callback type for sending a body retrieval request.
+type bodyRequesterFn func([]common.Hash) error
+
 // blockValidatorFn is a callback type to verify a block's header for fast propagation.
 type blockValidatorFn func(block *types.Block, parent *types.Block) error
 
@@ -69,11 +75,30 @@ type peerDropFn func(id string)
 // announce is the hash notification of the availability of a new block in the
 // network.
 type announce struct {
-	hash common.Hash // Hash of the block being announced
-	time time.Time   // Timestamp of the announcement
+	hash   common.Hash   // Hash of the block being announced
+	number uint64        // Number of the block being announced (0 = unknown | old protocol)
+	header *types.Header // Header of the block partially reassembled (new protocol)
+	time   time.Time     // Timestamp of the announcement
+
+	origin string // Identifier of the peer originating the notification
+
+	fetch61     blockRequesterFn  // [eth/61] Fetcher function to retrieve an announced block
+	fetchHeader headerRequesterFn // [eth/62] Fetcher function to retrieve the header of an announced block
+	fetchBodies bodyRequesterFn   // [eth/62] Fetcher function to retrieve the body of an announced block
+}
 
-	origin string           // Identifier of the peer originating the notification
-	fetch  blockRequesterFn // Fetcher function to retrieve
+// headerFilterTask represents a batch of headers needing fetcher filtering.
+type headerFilterTask struct {
+	headers []*types.Header // Collection of headers to filter
+	time    time.Time       // Arrival time of the headers
+}
+
+// headerFilterTask represents a batch of block bodies (transactions and uncles)
+// needing fetcher filtering.
+type bodyFilterTask struct {
+	transactions [][]*types.Transaction // Collection of transactions per block bodies
+	uncles       [][]*types.Header      // Collection of uncles per block bodies
+	time         time.Time              // Arrival time of the blocks' contents
 }
 
 // inject represents a schedules import operation.
@@ -88,14 +113,20 @@ type Fetcher struct {
 	// Various event channels
 	notify chan *announce
 	inject chan *inject
-	filter chan chan []*types.Block
-	done   chan common.Hash
-	quit   chan struct{}
+
+	blockFilter  chan chan []*types.Block
+	headerFilter chan chan *headerFilterTask
+	bodyFilter   chan chan *bodyFilterTask
+
+	done chan common.Hash
+	quit chan struct{}
 
 	// Announce states
-	announces map[string]int              // Per peer announce counts to prevent memory exhaustion
-	announced map[common.Hash][]*announce // Announced blocks, scheduled for fetching
-	fetching  map[common.Hash]*announce   // Announced blocks, currently fetching
+	announces  map[string]int              // Per peer announce counts to prevent memory exhaustion
+	announced  map[common.Hash][]*announce // Announced blocks, scheduled for fetching
+	fetching   map[common.Hash]*announce   // Announced blocks, currently fetching
+	fetched    map[common.Hash][]*announce // Blocks with headers fetched, scheduled for body retrieval
+	completing map[common.Hash]*announce   // Blocks with headers, currently body-completing
 
 	// Block cache
 	queue  *prque.Prque            // Queue containing the import operations (block number sorted)
@@ -111,8 +142,9 @@ type Fetcher struct {
 	dropPeer       peerDropFn         // Drops a peer for misbehaving
 
 	// Testing hooks
-	fetchingHook func([]common.Hash) // Method to call upon starting a block fetch
-	importedHook func(*types.Block)  // Method to call upon successful block import
+	fetchingHook   func([]common.Hash) // Method to call upon starting a block (eth/61) or header (eth/62) fetch
+	completingHook func([]common.Hash) // Method to call upon starting a block body fetch (eth/62)
+	importedHook   func(*types.Block)  // Method to call upon successful block import (both eth/61 and eth/62)
 }
 
 // New creates a block fetcher to retrieve blocks based on hash announcements.
@@ -120,12 +152,16 @@ func New(getBlock blockRetrievalFn, validateBlock blockValidatorFn, broadcastBlo
 	return &Fetcher{
 		notify:         make(chan *announce),
 		inject:         make(chan *inject),
-		filter:         make(chan chan []*types.Block),
+		blockFilter:    make(chan chan []*types.Block),
+		headerFilter:   make(chan chan *headerFilterTask),
+		bodyFilter:     make(chan chan *bodyFilterTask),
 		done:           make(chan common.Hash),
 		quit:           make(chan struct{}),
 		announces:      make(map[string]int),
 		announced:      make(map[common.Hash][]*announce),
 		fetching:       make(map[common.Hash]*announce),
+		fetched:        make(map[common.Hash][]*announce),
+		completing:     make(map[common.Hash]*announce),
 		queue:          prque.New(),
 		queues:         make(map[string]int),
 		queued:         make(map[common.Hash]*inject),
@@ -152,12 +188,17 @@ func (f *Fetcher) Stop() {
 
 // Notify announces the fetcher of the potential availability of a new block in
 // the network.
-func (f *Fetcher) Notify(peer string, hash common.Hash, time time.Time, fetcher blockRequesterFn) error {
+func (f *Fetcher) Notify(peer string, hash common.Hash, number uint64, time time.Time,
+	blockFetcher blockRequesterFn, // eth/61 specific whole block fetcher
+	headerFetcher headerRequesterFn, bodyFetcher bodyRequesterFn) error {
 	block := &announce{
-		hash:   hash,
-		time:   time,
-		origin: peer,
-		fetch:  fetcher,
+		hash:        hash,
+		number:      number,
+		time:        time,
+		origin:      peer,
+		fetch61:     blockFetcher,
+		fetchHeader: headerFetcher,
+		fetchBodies: bodyFetcher,
 	}
 	select {
 	case f.notify <- block:
@@ -181,14 +222,16 @@ func (f *Fetcher) Enqueue(peer string, block *types.Block) error {
 	}
 }
 
-// Filter extracts all the blocks that were explicitly requested by the fetcher,
+// FilterBlocks extracts all the blocks that were explicitly requested by the fetcher,
 // returning those that should be handled differently.
-func (f *Fetcher) Filter(blocks types.Blocks) types.Blocks {
+func (f *Fetcher) FilterBlocks(blocks types.Blocks) types.Blocks {
+	glog.V(logger.Detail).Infof("[eth/61] filtering %d blocks", len(blocks))
+
 	// Send the filter channel to the fetcher
 	filter := make(chan []*types.Block)
 
 	select {
-	case f.filter <- filter:
+	case f.blockFilter <- filter:
 	case <-f.quit:
 		return nil
 	}
@@ -207,11 +250,69 @@ func (f *Fetcher) Filter(blocks types.Blocks) types.Blocks {
 	}
 }
 
+// FilterHeaders extracts all the headers that were explicitly requested by the fetcher,
+// returning those that should be handled differently.
+func (f *Fetcher) FilterHeaders(headers []*types.Header, time time.Time) []*types.Header {
+	glog.V(logger.Detail).Infof("[eth/62] filtering %d headers", len(headers))
+
+	// Send the filter channel to the fetcher
+	filter := make(chan *headerFilterTask)
+
+	select {
+	case f.headerFilter <- filter:
+	case <-f.quit:
+		return nil
+	}
+	// Request the filtering of the header list
+	select {
+	case filter <- &headerFilterTask{headers: headers, time: time}:
+	case <-f.quit:
+		return nil
+	}
+	// Retrieve the headers remaining after filtering
+	select {
+	case task := <-filter:
+		return task.headers
+	case <-f.quit:
+		return nil
+	}
+}
+
+// FilterBodies extracts all the block bodies that were explicitly requested by
+// the fetcher, returning those that should be handled differently.
+func (f *Fetcher) FilterBodies(transactions [][]*types.Transaction, uncles [][]*types.Header, time time.Time) ([][]*types.Transaction, [][]*types.Header) {
+	glog.V(logger.Detail).Infof("[eth/62] filtering %d:%d bodies", len(transactions), len(uncles))
+
+	// Send the filter channel to the fetcher
+	filter := make(chan *bodyFilterTask)
+
+	select {
+	case f.bodyFilter <- filter:
+	case <-f.quit:
+		return nil, nil
+	}
+	// Request the filtering of the body list
+	select {
+	case filter <- &bodyFilterTask{transactions: transactions, uncles: uncles, time: time}:
+	case <-f.quit:
+		return nil, nil
+	}
+	// Retrieve the bodies remaining after filtering
+	select {
+	case task := <-filter:
+		return task.transactions, task.uncles
+	case <-f.quit:
+		return nil, nil
+	}
+}
+
 // Loop is the main fetcher loop, checking and processing various notification
 // events.
 func (f *Fetcher) loop() {
 	// Iterate the block fetching until a quit is requested
-	fetch := time.NewTimer(0)
+	fetchTimer := time.NewTimer(0)
+	completeTimer := time.NewTimer(0)
+
 	for {
 		// Clean up any expired block fetches
 		for hash, announce := range f.fetching {
@@ -246,26 +347,38 @@ func (f *Fetcher) loop() {
 
 		case notification := <-f.notify:
 			// A block was announced, make sure the peer isn't DOSing us
-			announceMeter.Mark(1)
+			propAnnounceInMeter.Mark(1)
 
 			count := f.announces[notification.origin] + 1
 			if count > hashLimit {
 				glog.V(logger.Debug).Infof("Peer %s: exceeded outstanding announces (%d)", notification.origin, hashLimit)
+				propAnnounceDOSMeter.Mark(1)
 				break
 			}
+			// If we have a valid block number, check that it's potentially useful
+			if notification.number > 0 {
+				if dist := int64(notification.number) - int64(f.chainHeight()); dist < -maxUncleDist || dist > maxQueueDist {
+					glog.V(logger.Debug).Infof("[eth/62] Peer %s: discarded announcement #%d [%x…], distance %d", notification.origin, notification.number, notification.hash[:4], dist)
+					propAnnounceDropMeter.Mark(1)
+					break
+				}
+			}
 			// All is well, schedule the announce if block's not yet downloading
 			if _, ok := f.fetching[notification.hash]; ok {
 				break
 			}
+			if _, ok := f.completing[notification.hash]; ok {
+				break
+			}
 			f.announces[notification.origin] = count
 			f.announced[notification.hash] = append(f.announced[notification.hash], notification)
 			if len(f.announced) == 1 {
-				f.reschedule(fetch)
+				f.rescheduleFetch(fetchTimer)
 			}
 
 		case op := <-f.inject:
 			// A direct block insertion was requested, try and fill any pending gaps
-			broadcastMeter.Mark(1)
+			propBroadcastInMeter.Mark(1)
 			f.enqueue(op.origin, op.block)
 
 		case hash := <-f.done:
@@ -273,7 +386,7 @@ func (f *Fetcher) loop() {
 			f.forgetHash(hash)
 			f.forgetBlock(hash)
 
-		case <-fetch.C:
+		case <-fetchTimer.C:
 			// At least one block's timer ran out, check for needing retrieval
 			request := make(map[string][]common.Hash)
 
@@ -290,30 +403,80 @@ func (f *Fetcher) loop() {
 					}
 				}
 			}
-			// Send out all block requests
+			// Send out all block (eth/61) or header (eth/62) requests
 			for peer, hashes := range request {
 				if glog.V(logger.Detail) && len(hashes) > 0 {
 					list := "["
 					for _, hash := range hashes {
-						list += fmt.Sprintf("%x, ", hash[:4])
+						list += fmt.Sprintf("%x…, ", hash[:4])
 					}
 					list = list[:len(list)-2] + "]"
 
-					glog.V(logger.Detail).Infof("Peer %s: fetching %s", peer, list)
+					if f.fetching[hashes[0]].fetch61 != nil {
+						glog.V(logger.Detail).Infof("[eth/61] Peer %s: fetching blocks %s", peer, list)
+					} else {
+						glog.V(logger.Detail).Infof("[eth/62] Peer %s: fetching headers %s", peer, list)
+					}
 				}
 				// Create a closure of the fetch and schedule in on a new thread
-				fetcher, hashes := f.fetching[hashes[0]].fetch, hashes
+				fetchBlocks, fetchHeader, hashes := f.fetching[hashes[0]].fetch61, f.fetching[hashes[0]].fetchHeader, hashes
 				go func() {
 					if f.fetchingHook != nil {
 						f.fetchingHook(hashes)
 					}
-					fetcher(hashes)
+					if fetchBlocks != nil {
+						// Use old eth/61 protocol to retrieve whole blocks
+						blockFetchMeter.Mark(int64(len(hashes)))
+						fetchBlocks(hashes)
+					} else {
+						// Use new eth/62 protocol to retrieve headers first
+						for _, hash := range hashes {
+							headerFetchMeter.Mark(1)
+							fetchHeader(hash) // Suboptimal, but protocol doesn't allow batch header retrievals
+						}
+					}
 				}()
 			}
 			// Schedule the next fetch if blocks are still pending
-			f.reschedule(fetch)
+			f.rescheduleFetch(fetchTimer)
+
+		case <-completeTimer.C:
+			// At least one header's timer ran out, retrieve everything
+			request := make(map[string][]common.Hash)
+
+			for hash, announces := range f.fetched {
+				// Pick a random peer to retrieve from, reset all others
+				announce := announces[rand.Intn(len(announces))]
+				f.forgetHash(hash)
+
+				// If the block still didn't arrive, queue for completion
+				if f.getBlock(hash) == nil {
+					request[announce.origin] = append(request[announce.origin], hash)
+					f.completing[hash] = announce
+				}
+			}
+			// Send out all block body requests
+			for peer, hashes := range request {
+				if glog.V(logger.Detail) && len(hashes) > 0 {
+					list := "["
+					for _, hash := range hashes {
+						list += fmt.Sprintf("%x…, ", hash[:4])
+					}
+					list = list[:len(list)-2] + "]"
+
+					glog.V(logger.Detail).Infof("[eth/62] Peer %s: fetching bodies %s", peer, list)
+				}
+				// Create a closure of the fetch and schedule in on a new thread
+				if f.completingHook != nil {
+					f.completingHook(hashes)
+				}
+				bodyFetchMeter.Mark(int64(len(hashes)))
+				go f.completing[hashes[0]].fetchBodies(hashes)
+			}
+			// Schedule the next fetch if blocks are still pending
+			f.rescheduleComplete(completeTimer)
 
-		case filter := <-f.filter:
+		case filter := <-f.blockFilter:
 			// Blocks arrived, extract any explicit fetches, return all else
 			var blocks types.Blocks
 			select {
@@ -321,6 +484,7 @@ func (f *Fetcher) loop() {
 			case <-f.quit:
 				return
 			}
+			blockFilterInMeter.Mark(int64(len(blocks)))
 
 			explicit, download := []*types.Block{}, []*types.Block{}
 			for _, block := range blocks {
@@ -339,6 +503,7 @@ func (f *Fetcher) loop() {
 				}
 			}
 
+			blockFilterOutMeter.Mark(int64(len(download)))
 			select {
 			case filter <- download:
 			case <-f.quit:
@@ -350,12 +515,146 @@ func (f *Fetcher) loop() {
 					f.enqueue(announce.origin, block)
 				}
 			}
+
+		case filter := <-f.headerFilter:
+			// Headers arrived from a remote peer. Extract those that were explicitly
+			// requested by the fetcher, and return everything else so it's delivered
+			// to other parts of the system.
+			var task *headerFilterTask
+			select {
+			case task = <-filter:
+			case <-f.quit:
+				return
+			}
+			headerFilterInMeter.Mark(int64(len(task.headers)))
+
+			// Split the batch of headers into unknown ones (to return to the caller),
+			// known incomplete ones (requiring body retrievals) and completed blocks.
+			unknown, incomplete, complete := []*types.Header{}, []*announce{}, []*types.Block{}
+			for _, header := range task.headers {
+				hash := header.Hash()
+
+				// Filter fetcher-requested headers from other synchronisation algorithms
+				if announce := f.fetching[hash]; announce != nil && f.fetched[hash] == nil && f.completing[hash] == nil && f.queued[hash] == nil {
+					// If the delivered header does not match the promised number, drop the announcer
+					if header.Number.Uint64() != announce.number {
+						glog.V(logger.Detail).Infof("[eth/62] Peer %s: invalid block number for [%x…]: announced %d, provided %d", announce.origin, header.Hash().Bytes()[:4], announce.number, header.Number.Uint64())
+						f.dropPeer(announce.origin)
+						f.forgetHash(hash)
+						continue
+					}
+					// Only keep if not imported by other means
+					if f.getBlock(hash) == nil {
+						announce.header = header
+						announce.time = task.time
+
+						// If the block is empty (header only), short circuit into the final import queue
+						if header.TxHash == types.DeriveSha(types.Transactions{}) && header.UncleHash == types.CalcUncleHash([]*types.Header{}) {
+							glog.V(logger.Detail).Infof("[eth/62] Peer %s: block #%d [%x…] empty, skipping body retrieval", announce.origin, header.Number.Uint64(), header.Hash().Bytes()[:4])
+
+							block := types.NewBlockWithHeader(header)
+							block.ReceivedAt = task.time
+
+							complete = append(complete, block)
+							f.completing[hash] = announce
+							continue
+						}
+						// Otherwise add to the list of blocks needing completion
+						incomplete = append(incomplete, announce)
+					} else {
+						glog.V(logger.Detail).Infof("[eth/62] Peer %s: block #%d [%x…] already imported, discarding header", announce.origin, header.Number.Uint64(), header.Hash().Bytes()[:4])
+						f.forgetHash(hash)
+					}
+				} else {
+					// Fetcher doesn't know about it, add to the return list
+					unknown = append(unknown, header)
+				}
+			}
+			headerFilterOutMeter.Mark(int64(len(unknown)))
+			select {
+			case filter <- &headerFilterTask{headers: unknown, time: task.time}:
+			case <-f.quit:
+				return
+			}
+			// Schedule the retrieved headers for body completion
+			for _, announce := range incomplete {
+				hash := announce.header.Hash()
+				if _, ok := f.completing[hash]; ok {
+					continue
+				}
+				f.fetched[hash] = append(f.fetched[hash], announce)
+				if len(f.fetched) == 1 {
+					f.rescheduleComplete(completeTimer)
+				}
+			}
+			// Schedule the header-only blocks for import
+			for _, block := range complete {
+				if announce := f.completing[block.Hash()]; announce != nil {
+					f.enqueue(announce.origin, block)
+				}
+			}
+
+		case filter := <-f.bodyFilter:
+			// Block bodies arrived, extract any explicitly requested blocks, return the rest
+			var task *bodyFilterTask
+			select {
+			case task = <-filter:
+			case <-f.quit:
+				return
+			}
+			bodyFilterInMeter.Mark(int64(len(task.transactions)))
+
+			blocks := []*types.Block{}
+			for i := 0; i < len(task.transactions) && i < len(task.uncles); i++ {
+				// Match up a body to any possible completion request
+				matched := false
+
+				for hash, announce := range f.completing {
+					if f.queued[hash] == nil {
+						txnHash := types.DeriveSha(types.Transactions(task.transactions[i]))
+						uncleHash := types.CalcUncleHash(task.uncles[i])
+
+						if txnHash == announce.header.TxHash && uncleHash == announce.header.UncleHash {
+							// Mark the body matched, reassemble if still unknown
+							matched = true
+
+							if f.getBlock(hash) == nil {
+								block := types.NewBlockWithHeader(announce.header).WithBody(task.transactions[i], task.uncles[i])
+								block.ReceivedAt = task.time
+
+								blocks = append(blocks, block)
+							} else {
+								f.forgetHash(hash)
+							}
+						}
+					}
+				}
+				if matched {
+					task.transactions = append(task.transactions[:i], task.transactions[i+1:]...)
+					task.uncles = append(task.uncles[:i], task.uncles[i+1:]...)
+					i--
+					continue
+				}
+			}
+
+			bodyFilterOutMeter.Mark(int64(len(task.transactions)))
+			select {
+			case filter <- task:
+			case <-f.quit:
+				return
+			}
+			// Schedule the retrieved blocks for ordered import
+			for _, block := range blocks {
+				if announce := f.completing[block.Hash()]; announce != nil {
+					f.enqueue(announce.origin, block)
+				}
+			}
 		}
 	}
 }
 
-// reschedule resets the specified fetch timer to the next announce timeout.
-func (f *Fetcher) reschedule(fetch *time.Timer) {
+// rescheduleFetch resets the specified fetch timer to the next announce timeout.
+func (f *Fetcher) rescheduleFetch(fetch *time.Timer) {
 	// Short circuit if no blocks are announced
 	if len(f.announced) == 0 {
 		return
@@ -370,6 +669,22 @@ func (f *Fetcher) reschedule(fetch *time.Timer) {
 	fetch.Reset(arriveTimeout - time.Since(earliest))
 }
 
+// rescheduleComplete resets the specified completion timer to the next fetch timeout.
+func (f *Fetcher) rescheduleComplete(complete *time.Timer) {
+	// Short circuit if no headers are fetched
+	if len(f.fetched) == 0 {
+		return
+	}
+	// Otherwise find the earliest expiring announcement
+	earliest := time.Now()
+	for _, announces := range f.fetched {
+		if earliest.After(announces[0].time) {
+			earliest = announces[0].time
+		}
+	}
+	complete.Reset(gatherSlack - time.Since(earliest))
+}
+
 // enqueue schedules a new future import operation, if the block to be imported
 // has not yet been seen.
 func (f *Fetcher) enqueue(peer string, block *types.Block) {
@@ -378,13 +693,16 @@ func (f *Fetcher) enqueue(peer string, block *types.Block) {
 	// Ensure the peer isn't DOSing us
 	count := f.queues[peer] + 1
 	if count > blockLimit {
-		glog.V(logger.Debug).Infof("Peer %s: discarded block #%d [%x], exceeded allowance (%d)", peer, block.NumberU64(), hash.Bytes()[:4], blockLimit)
+		glog.V(logger.Debug).Infof("Peer %s: discarded block #%d [%x…], exceeded allowance (%d)", peer, block.NumberU64(), hash.Bytes()[:4], blockLimit)
+		propBroadcastDOSMeter.Mark(1)
+		f.forgetHash(hash)
 		return
 	}
 	// Discard any past or too distant blocks
 	if dist := int64(block.NumberU64()) - int64(f.chainHeight()); dist < -maxUncleDist || dist > maxQueueDist {
-		glog.V(logger.Debug).Infof("Peer %s: discarded block #%d [%x], distance %d", peer, block.NumberU64(), hash.Bytes()[:4], dist)
-		discardMeter.Mark(1)
+		glog.V(logger.Debug).Infof("Peer %s: discarded block #%d [%x…], distance %d", peer, block.NumberU64(), hash.Bytes()[:4], dist)
+		propBroadcastDropMeter.Mark(1)
+		f.forgetHash(hash)
 		return
 	}
 	// Schedule the block for future importing
@@ -398,7 +716,7 @@ func (f *Fetcher) enqueue(peer string, block *types.Block) {
 		f.queue.Push(op, -float32(block.NumberU64()))
 
 		if glog.V(logger.Debug) {
-			glog.Infof("Peer %s: queued block #%d [%x], total %v", peer, block.NumberU64(), hash.Bytes()[:4], f.queue.Size())
+			glog.Infof("Peer %s: queued block #%d [%x…], total %v", peer, block.NumberU64(), hash.Bytes()[:4], f.queue.Size())
 		}
 	}
 }
@@ -410,39 +728,39 @@ func (f *Fetcher) insert(peer string, block *types.Block) {
 	hash := block.Hash()
 
 	// Run the import on a new thread
-	glog.V(logger.Debug).Infof("Peer %s: importing block #%d [%x]", peer, block.NumberU64(), hash[:4])
+	glog.V(logger.Debug).Infof("Peer %s: importing block #%d [%x…]", peer, block.NumberU64(), hash[:4])
 	go func() {
 		defer func() { f.done <- hash }()
 
 		// If the parent's unknown, abort insertion
 		parent := f.getBlock(block.ParentHash())
 		if parent == nil {
+			glog.V(logger.Debug).Infof("Peer %s: parent []%x] of block #%d [%x…] unknown", block.ParentHash().Bytes()[:4], peer, block.NumberU64(), hash[:4])
 			return
 		}
 		// Quickly validate the header and propagate the block if it passes
 		switch err := f.validateBlock(block, parent); err {
 		case nil:
 			// All ok, quickly propagate to our peers
-			broadcastTimer.UpdateSince(block.ReceivedAt)
+			propBroadcastOutTimer.UpdateSince(block.ReceivedAt)
 			go f.broadcastBlock(block, true)
 
 		case core.BlockFutureErr:
-			futureMeter.Mark(1)
 			// Weird future block, don't fail, but neither propagate
 
 		default:
 			// Something went very wrong, drop the peer
-			glog.V(logger.Debug).Infof("Peer %s: block #%d [%x] verification failed: %v", peer, block.NumberU64(), hash[:4], err)
+			glog.V(logger.Debug).Infof("Peer %s: block #%d [%x…] verification failed: %v", peer, block.NumberU64(), hash[:4], err)
 			f.dropPeer(peer)
 			return
 		}
 		// Run the actual import and log any issues
 		if _, err := f.insertChain(types.Blocks{block}); err != nil {
-			glog.V(logger.Warn).Infof("Peer %s: block #%d [%x] import failed: %v", peer, block.NumberU64(), hash[:4], err)
+			glog.V(logger.Warn).Infof("Peer %s: block #%d [%x…] import failed: %v", peer, block.NumberU64(), hash[:4], err)
 			return
 		}
 		// If import succeeded, broadcast the block
-		announceTimer.UpdateSince(block.ReceivedAt)
+		propAnnounceOutTimer.UpdateSince(block.ReceivedAt)
 		go f.broadcastBlock(block, false)
 
 		// Invoke the testing hook if needed
@@ -472,9 +790,27 @@ func (f *Fetcher) forgetHash(hash common.Hash) {
 		}
 		delete(f.fetching, hash)
 	}
+
+	// Remove any pending completion requests and decrement the DOS counters
+	for _, announce := range f.fetched[hash] {
+		f.announces[announce.origin]--
+		if f.announces[announce.origin] == 0 {
+			delete(f.announces, announce.origin)
+		}
+	}
+	delete(f.fetched, hash)
+
+	// Remove any pending completions and decrement the DOS counters
+	if announce := f.completing[hash]; announce != nil {
+		f.announces[announce.origin]--
+		if f.announces[announce.origin] == 0 {
+			delete(f.announces, announce.origin)
+		}
+		delete(f.completing, hash)
+	}
 }
 
-// forgetBlock removes all traces of a queued block frmo the fetcher's internal
+// forgetBlock removes all traces of a queued block from the fetcher's internal
 // state.
 func (f *Fetcher) forgetBlock(hash common.Hash) {
 	if insert := f.queued[hash]; insert != nil {
diff --git a/eth/fetcher/fetcher_test.go b/eth/fetcher/fetcher_test.go
index ecbb3f868..707d8d758 100644
--- a/eth/fetcher/fetcher_test.go
+++ b/eth/fetcher/fetcher_test.go
@@ -27,21 +27,39 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/params"
 )
 
 var (
 	testdb, _    = ethdb.NewMemDatabase()
-	genesis      = core.GenesisBlockForTesting(testdb, common.Address{}, big.NewInt(0))
+	testKey, _   = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+	testAddress  = crypto.PubkeyToAddress(testKey.PublicKey)
+	genesis      = core.GenesisBlockForTesting(testdb, testAddress, big.NewInt(1000000000))
 	unknownBlock = types.NewBlock(&types.Header{GasLimit: params.GenesisGasLimit}, nil, nil, nil)
 )
 
 // makeChain creates a chain of n blocks starting at and including parent.
-// the returned hash chain is ordered head->parent.
+// the returned hash chain is ordered head->parent. In addition, every 3rd block
+// contains a transaction and every 5th an uncle to allow testing correct block
+// reassembly.
 func makeChain(n int, seed byte, parent *types.Block) ([]common.Hash, map[common.Hash]*types.Block) {
-	blocks := core.GenerateChain(parent, testdb, n, func(i int, gen *core.BlockGen) {
-		gen.SetCoinbase(common.Address{seed})
+	blocks := core.GenerateChain(parent, testdb, n, func(i int, block *core.BlockGen) {
+		block.SetCoinbase(common.Address{seed})
+
+		// If the block number is multiple of 3, send a bonus transaction to the miner
+		if parent == genesis && i%3 == 0 {
+			tx, err := types.NewTransaction(block.TxNonce(testAddress), common.Address{seed}, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(testKey)
+			if err != nil {
+				panic(err)
+			}
+			block.AddTx(tx)
+		}
+		// If the block number is a multiple of 5, add a bonus uncle to the block
+		if i%5 == 0 {
+			block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 1).Hash(), Number: big.NewInt(int64(i - 1))})
+		}
 	})
 	hashes := make([]common.Hash, n+1)
 	hashes[len(hashes)-1] = parent.Hash()
@@ -60,6 +78,7 @@ type fetcherTester struct {
 
 	hashes []common.Hash                // Hash chain belonging to the tester
 	blocks map[common.Hash]*types.Block // Blocks belonging to the tester
+	drops  map[string]bool              // Map of peers dropped by the fetcher
 
 	lock sync.RWMutex
 }
@@ -69,6 +88,7 @@ func newTester() *fetcherTester {
 	tester := &fetcherTester{
 		hashes: []common.Hash{genesis.Hash()},
 		blocks: map[common.Hash]*types.Block{genesis.Hash(): genesis},
+		drops:  make(map[string]bool),
 	}
 	tester.fetcher = New(tester.getBlock, tester.verifyBlock, tester.broadcastBlock, tester.chainHeight, tester.insertChain, tester.dropPeer)
 	tester.fetcher.Start()
@@ -122,12 +142,14 @@ func (f *fetcherTester) insertChain(blocks types.Blocks) (int, error) {
 	return 0, nil
 }
 
-// dropPeer is a nop placeholder for the peer removal.
+// dropPeer is an emulator for the peer removal, simply accumulating the various
+// peers dropped by the fetcher.
 func (f *fetcherTester) dropPeer(peer string) {
+	f.drops[peer] = true
 }
 
-// peerFetcher retrieves a fetcher associated with a simulated peer.
-func (f *fetcherTester) makeFetcher(blocks map[common.Hash]*types.Block) blockRequesterFn {
+// makeBlockFetcher retrieves a block fetcher associated with a simulated peer.
+func (f *fetcherTester) makeBlockFetcher(blocks map[common.Hash]*types.Block) blockRequesterFn {
 	closure := make(map[common.Hash]*types.Block)
 	for hash, block := range blocks {
 		closure[hash] = block
@@ -142,18 +164,105 @@ func (f *fetcherTester) makeFetcher(blocks map[common.Hash]*types.Block) blockRe
 			}
 		}
 		// Return on a new thread
-		go f.fetcher.Filter(blocks)
+		go f.fetcher.FilterBlocks(blocks)
+
+		return nil
+	}
+}
+
+// makeHeaderFetcher retrieves a block header fetcher associated with a simulated peer.
+func (f *fetcherTester) makeHeaderFetcher(blocks map[common.Hash]*types.Block, drift time.Duration) headerRequesterFn {
+	closure := make(map[common.Hash]*types.Block)
+	for hash, block := range blocks {
+		closure[hash] = block
+	}
+	// Create a function that return a header from the closure
+	return func(hash common.Hash) error {
+		// Gather the blocks to return
+		headers := make([]*types.Header, 0, 1)
+		if block, ok := closure[hash]; ok {
+			headers = append(headers, block.Header())
+		}
+		// Return on a new thread
+		go f.fetcher.FilterHeaders(headers, time.Now().Add(drift))
+
+		return nil
+	}
+}
+
+// makeBodyFetcher retrieves a block body fetcher associated with a simulated peer.
+func (f *fetcherTester) makeBodyFetcher(blocks map[common.Hash]*types.Block, drift time.Duration) bodyRequesterFn {
+	closure := make(map[common.Hash]*types.Block)
+	for hash, block := range blocks {
+		closure[hash] = block
+	}
+	// Create a function that returns blocks from the closure
+	return func(hashes []common.Hash) error {
+		// Gather the block bodies to return
+		transactions := make([][]*types.Transaction, 0, len(hashes))
+		uncles := make([][]*types.Header, 0, len(hashes))
+
+		for _, hash := range hashes {
+			if block, ok := closure[hash]; ok {
+				transactions = append(transactions, block.Transactions())
+				uncles = append(uncles, block.Uncles())
+			}
+		}
+		// Return on a new thread
+		go f.fetcher.FilterBodies(transactions, uncles, time.Now().Add(drift))
 
 		return nil
 	}
 }
 
+// verifyFetchingEvent verifies that one single event arrive on an fetching channel.
+func verifyFetchingEvent(t *testing.T, fetching chan []common.Hash, arrive bool) {
+	if arrive {
+		select {
+		case <-fetching:
+		case <-time.After(time.Second):
+			t.Fatalf("fetching timeout")
+		}
+	} else {
+		select {
+		case <-fetching:
+			t.Fatalf("fetching invoked")
+		case <-time.After(10 * time.Millisecond):
+		}
+	}
+}
+
+// verifyCompletingEvent verifies that one single event arrive on an completing channel.
+func verifyCompletingEvent(t *testing.T, completing chan []common.Hash, arrive bool) {
+	if arrive {
+		select {
+		case <-completing:
+		case <-time.After(time.Second):
+			t.Fatalf("completing timeout")
+		}
+	} else {
+		select {
+		case <-completing:
+			t.Fatalf("completing invoked")
+		case <-time.After(10 * time.Millisecond):
+		}
+	}
+}
+
 // verifyImportEvent verifies that one single event arrive on an import channel.
-func verifyImportEvent(t *testing.T, imported chan *types.Block) {
-	select {
-	case <-imported:
-	case <-time.After(time.Second):
-		t.Fatalf("import timeout")
+func verifyImportEvent(t *testing.T, imported chan *types.Block, arrive bool) {
+	if arrive {
+		select {
+		case <-imported:
+		case <-time.After(time.Second):
+			t.Fatalf("import timeout")
+		}
+	} else {
+		select {
+		case <-imported:
+			t.Fatalf("import invoked")
+		case <-time.After(10 * time.Millisecond):
+		}
 	}
 }
 
@@ -164,7 +273,7 @@ func verifyImportCount(t *testing.T, imported chan *types.Block, count int) {
 		select {
 		case <-imported:
 		case <-time.After(time.Second):
-			t.Fatalf("block %d: import timeout", i)
+			t.Fatalf("block %d: import timeout", i+1)
 		}
 	}
 	verifyImportDone(t, imported)
@@ -181,51 +290,78 @@ func verifyImportDone(t *testing.T, imported chan *types.Block) {
 
 // Tests that a fetcher accepts block announcements and initiates retrievals for
 // them, successfully importing into the local chain.
-func TestSequentialAnnouncements(t *testing.T) {
+func TestSequentialAnnouncements61(t *testing.T) { testSequentialAnnouncements(t, 61) }
+func TestSequentialAnnouncements62(t *testing.T) { testSequentialAnnouncements(t, 62) }
+func TestSequentialAnnouncements63(t *testing.T) { testSequentialAnnouncements(t, 63) }
+func TestSequentialAnnouncements64(t *testing.T) { testSequentialAnnouncements(t, 64) }
+
+func testSequentialAnnouncements(t *testing.T, protocol int) {
 	// Create a chain of blocks to import
 	targetBlocks := 4 * hashLimit
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	// Iteratively announce blocks until all are imported
 	imported := make(chan *types.Block)
 	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
 
 	for i := len(hashes) - 2; i >= 0; i-- {
-		tester.fetcher.Notify("valid", hashes[i], time.Now().Add(-arriveTimeout), fetcher)
-		verifyImportEvent(t, imported)
+		if protocol < 62 {
+			tester.fetcher.Notify("valid", hashes[i], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+		} else {
+			tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+		}
+		verifyImportEvent(t, imported, true)
 	}
 	verifyImportDone(t, imported)
 }
 
 // Tests that if blocks are announced by multiple peers (or even the same buggy
 // peer), they will only get downloaded at most once.
-func TestConcurrentAnnouncements(t *testing.T) {
+func TestConcurrentAnnouncements61(t *testing.T) { testConcurrentAnnouncements(t, 61) }
+func TestConcurrentAnnouncements62(t *testing.T) { testConcurrentAnnouncements(t, 62) }
+func TestConcurrentAnnouncements63(t *testing.T) { testConcurrentAnnouncements(t, 63) }
+func TestConcurrentAnnouncements64(t *testing.T) { testConcurrentAnnouncements(t, 64) }
+
+func testConcurrentAnnouncements(t *testing.T, protocol int) {
 	// Create a chain of blocks to import
 	targetBlocks := 4 * hashLimit
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
 	// Assemble a tester with a built in counter for the requests
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	counter := uint32(0)
-	wrapper := func(hashes []common.Hash) error {
+	blockWrapper := func(hashes []common.Hash) error {
 		atomic.AddUint32(&counter, uint32(len(hashes)))
-		return fetcher(hashes)
+		return blockFetcher(hashes)
+	}
+	headerWrapper := func(hash common.Hash) error {
+		atomic.AddUint32(&counter, 1)
+		return headerFetcher(hash)
 	}
 	// Iteratively announce blocks until all are imported
 	imported := make(chan *types.Block)
 	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
 
 	for i := len(hashes) - 2; i >= 0; i-- {
-		tester.fetcher.Notify("first", hashes[i], time.Now().Add(-arriveTimeout), wrapper)
-		tester.fetcher.Notify("second", hashes[i], time.Now().Add(-arriveTimeout+time.Millisecond), wrapper)
-		tester.fetcher.Notify("second", hashes[i], time.Now().Add(-arriveTimeout-time.Millisecond), wrapper)
-
-		verifyImportEvent(t, imported)
+		if protocol < 62 {
+			tester.fetcher.Notify("first", hashes[i], 0, time.Now().Add(-arriveTimeout), blockWrapper, nil, nil)
+			tester.fetcher.Notify("second", hashes[i], 0, time.Now().Add(-arriveTimeout+time.Millisecond), blockWrapper, nil, nil)
+			tester.fetcher.Notify("second", hashes[i], 0, time.Now().Add(-arriveTimeout-time.Millisecond), blockWrapper, nil, nil)
+		} else {
+			tester.fetcher.Notify("first", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerWrapper, bodyFetcher)
+			tester.fetcher.Notify("second", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout+time.Millisecond), nil, headerWrapper, bodyFetcher)
+			tester.fetcher.Notify("second", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout-time.Millisecond), nil, headerWrapper, bodyFetcher)
+		}
+		verifyImportEvent(t, imported, true)
 	}
 	verifyImportDone(t, imported)
 
@@ -237,56 +373,90 @@ func TestConcurrentAnnouncements(t *testing.T) {
 
 // Tests that announcements arriving while a previous is being fetched still
 // results in a valid import.
-func TestOverlappingAnnouncements(t *testing.T) {
+func TestOverlappingAnnouncements61(t *testing.T) { testOverlappingAnnouncements(t, 61) }
+func TestOverlappingAnnouncements62(t *testing.T) { testOverlappingAnnouncements(t, 62) }
+func TestOverlappingAnnouncements63(t *testing.T) { testOverlappingAnnouncements(t, 63) }
+func TestOverlappingAnnouncements64(t *testing.T) { testOverlappingAnnouncements(t, 64) }
+
+func testOverlappingAnnouncements(t *testing.T, protocol int) {
 	// Create a chain of blocks to import
 	targetBlocks := 4 * hashLimit
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	// Iteratively announce blocks, but overlap them continuously
-	fetching := make(chan []common.Hash)
+	overlap := 16
 	imported := make(chan *types.Block, len(hashes)-1)
-	tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- hashes }
+	for i := 0; i < overlap; i++ {
+		imported <- nil
+	}
 	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
 
 	for i := len(hashes) - 2; i >= 0; i-- {
-		tester.fetcher.Notify("valid", hashes[i], time.Now().Add(-arriveTimeout), fetcher)
+		if protocol < 62 {
+			tester.fetcher.Notify("valid", hashes[i], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+		} else {
+			tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+		}
 		select {
-		case <-fetching:
+		case <-imported:
 		case <-time.After(time.Second):
-			t.Fatalf("hash %d: announce timeout", len(hashes)-i)
+			t.Fatalf("block %d: import timeout", len(hashes)-i)
 		}
 	}
 	// Wait for all the imports to complete and check count
-	verifyImportCount(t, imported, len(hashes)-1)
+	verifyImportCount(t, imported, overlap)
 }
 
 // Tests that announces already being retrieved will not be duplicated.
-func TestPendingDeduplication(t *testing.T) {
+func TestPendingDeduplication61(t *testing.T) { testPendingDeduplication(t, 61) }
+func TestPendingDeduplication62(t *testing.T) { testPendingDeduplication(t, 62) }
+func TestPendingDeduplication63(t *testing.T) { testPendingDeduplication(t, 63) }
+func TestPendingDeduplication64(t *testing.T) { testPendingDeduplication(t, 64) }
+
+func testPendingDeduplication(t *testing.T, protocol int) {
 	// Create a hash and corresponding block
 	hashes, blocks := makeChain(1, 0, genesis)
 
 	// Assemble a tester with a built in counter and delayed fetcher
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	delay := 50 * time.Millisecond
 	counter := uint32(0)
-	wrapper := func(hashes []common.Hash) error {
+	blockWrapper := func(hashes []common.Hash) error {
 		atomic.AddUint32(&counter, uint32(len(hashes)))
 
 		// Simulate a long running fetch
 		go func() {
 			time.Sleep(delay)
-			fetcher(hashes)
+			blockFetcher(hashes)
+		}()
+		return nil
+	}
+	headerWrapper := func(hash common.Hash) error {
+		atomic.AddUint32(&counter, 1)
+
+		// Simulate a long running fetch
+		go func() {
+			time.Sleep(delay)
+			headerFetcher(hash)
 		}()
 		return nil
 	}
 	// Announce the same block many times until it's fetched (wait for any pending ops)
 	for tester.getBlock(hashes[0]) == nil {
-		tester.fetcher.Notify("repeater", hashes[0], time.Now().Add(-arriveTimeout), wrapper)
+		if protocol < 62 {
+			tester.fetcher.Notify("repeater", hashes[0], 0, time.Now().Add(-arriveTimeout), blockWrapper, nil, nil)
+		} else {
+			tester.fetcher.Notify("repeater", hashes[0], 1, time.Now().Add(-arriveTimeout), nil, headerWrapper, bodyFetcher)
+		}
 		time.Sleep(time.Millisecond)
 	}
 	time.Sleep(delay)
@@ -302,14 +472,21 @@ func TestPendingDeduplication(t *testing.T) {
 
 // Tests that announcements retrieved in a random order are cached and eventually
 // imported when all the gaps are filled in.
-func TestRandomArrivalImport(t *testing.T) {
+func TestRandomArrivalImport61(t *testing.T) { testRandomArrivalImport(t, 61) }
+func TestRandomArrivalImport62(t *testing.T) { testRandomArrivalImport(t, 62) }
+func TestRandomArrivalImport63(t *testing.T) { testRandomArrivalImport(t, 63) }
+func TestRandomArrivalImport64(t *testing.T) { testRandomArrivalImport(t, 64) }
+
+func testRandomArrivalImport(t *testing.T, protocol int) {
 	// Create a chain of blocks to import, and choose one to delay
 	targetBlocks := maxQueueDist
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 	skip := targetBlocks / 2
 
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	// Iteratively announce blocks, skipping one entry
 	imported := make(chan *types.Block, len(hashes)-1)
@@ -317,25 +494,40 @@ func TestRandomArrivalImport(t *testing.T) {
 
 	for i := len(hashes) - 1; i >= 0; i-- {
 		if i != skip {
-			tester.fetcher.Notify("valid", hashes[i], time.Now().Add(-arriveTimeout), fetcher)
+			if protocol < 62 {
+				tester.fetcher.Notify("valid", hashes[i], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+			} else {
+				tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+			}
 			time.Sleep(time.Millisecond)
 		}
 	}
 	// Finally announce the skipped entry and check full import
-	tester.fetcher.Notify("valid", hashes[skip], time.Now().Add(-arriveTimeout), fetcher)
+	if protocol < 62 {
+		tester.fetcher.Notify("valid", hashes[skip], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+	} else {
+		tester.fetcher.Notify("valid", hashes[skip], uint64(len(hashes)-skip-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	}
 	verifyImportCount(t, imported, len(hashes)-1)
 }
 
 // Tests that direct block enqueues (due to block propagation vs. hash announce)
 // are correctly schedule, filling and import queue gaps.
-func TestQueueGapFill(t *testing.T) {
+func TestQueueGapFill61(t *testing.T) { testQueueGapFill(t, 61) }
+func TestQueueGapFill62(t *testing.T) { testQueueGapFill(t, 62) }
+func TestQueueGapFill63(t *testing.T) { testQueueGapFill(t, 63) }
+func TestQueueGapFill64(t *testing.T) { testQueueGapFill(t, 64) }
+
+func testQueueGapFill(t *testing.T, protocol int) {
 	// Create a chain of blocks to import, and choose one to not announce at all
 	targetBlocks := maxQueueDist
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
 	skip := targetBlocks / 2
 
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	// Iteratively announce blocks, skipping one entry
 	imported := make(chan *types.Block, len(hashes)-1)
@@ -343,7 +535,11 @@ func TestQueueGapFill(t *testing.T) {
 
 	for i := len(hashes) - 1; i >= 0; i-- {
 		if i != skip {
-			tester.fetcher.Notify("valid", hashes[i], time.Now().Add(-arriveTimeout), fetcher)
+			if protocol < 62 {
+				tester.fetcher.Notify("valid", hashes[i], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+			} else {
+				tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+			}
 			time.Sleep(time.Millisecond)
 		}
 	}
@@ -354,13 +550,20 @@ func TestQueueGapFill(t *testing.T) {
 
 // Tests that blocks arriving from various sources (multiple propagations, hash
 // announces, etc) do not get scheduled for import multiple times.
-func TestImportDeduplication(t *testing.T) {
+func TestImportDeduplication61(t *testing.T) { testImportDeduplication(t, 61) }
+func TestImportDeduplication62(t *testing.T) { testImportDeduplication(t, 62) }
+func TestImportDeduplication63(t *testing.T) { testImportDeduplication(t, 63) }
+func TestImportDeduplication64(t *testing.T) { testImportDeduplication(t, 64) }
+
+func testImportDeduplication(t *testing.T, protocol int) {
 	// Create two blocks to import (one for duplication, the other for stalling)
 	hashes, blocks := makeChain(2, 0, genesis)
 
 	// Create the tester and wrap the importer with a counter
 	tester := newTester()
-	fetcher := tester.makeFetcher(blocks)
+	blockFetcher := tester.makeBlockFetcher(blocks)
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	counter := uint32(0)
 	tester.fetcher.insertChain = func(blocks types.Blocks) (int, error) {
@@ -374,7 +577,11 @@ func TestImportDeduplication(t *testing.T) {
 	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
 
 	// Announce the duplicating block, wait for retrieval, and also propagate directly
-	tester.fetcher.Notify("valid", hashes[0], time.Now().Add(-arriveTimeout), fetcher)
+	if protocol < 62 {
+		tester.fetcher.Notify("valid", hashes[0], 0, time.Now().Add(-arriveTimeout), blockFetcher, nil, nil)
+	} else {
+		tester.fetcher.Notify("valid", hashes[0], 1, time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	}
 	<-fetching
 
 	tester.fetcher.Enqueue("valid", blocks[hashes[0]])
@@ -391,35 +598,157 @@ func TestImportDeduplication(t *testing.T) {
 }
 
 // Tests that blocks with numbers much lower or higher than out current head get
-// discarded no prevent wasting resources on useless blocks from faulty peers.
-func TestDistantDiscarding(t *testing.T) {
-	// Create a long chain to import
+// discarded to prevent wasting resources on useless blocks from faulty peers.
+func TestDistantPropagationDiscarding(t *testing.T) {
+	// Create a long chain to import and define the discard boundaries
 	hashes, blocks := makeChain(3*maxQueueDist, 0, genesis)
 	head := hashes[len(hashes)/2]
 
+	low, high := len(hashes)/2+maxUncleDist+1, len(hashes)/2-maxQueueDist-1
+
 	// Create a tester and simulate a head block being the middle of the above chain
 	tester := newTester()
 	tester.hashes = []common.Hash{head}
 	tester.blocks = map[common.Hash]*types.Block{head: blocks[head]}
 
 	// Ensure that a block with a lower number than the threshold is discarded
-	tester.fetcher.Enqueue("lower", blocks[hashes[0]])
+	tester.fetcher.Enqueue("lower", blocks[hashes[low]])
 	time.Sleep(10 * time.Millisecond)
 	if !tester.fetcher.queue.Empty() {
 		t.Fatalf("fetcher queued stale block")
 	}
 	// Ensure that a block with a higher number than the threshold is discarded
-	tester.fetcher.Enqueue("higher", blocks[hashes[len(hashes)-1]])
+	tester.fetcher.Enqueue("higher", blocks[hashes[high]])
 	time.Sleep(10 * time.Millisecond)
 	if !tester.fetcher.queue.Empty() {
 		t.Fatalf("fetcher queued future block")
 	}
 }
 
+// Tests that announcements with numbers much lower or higher than out current
+// head get discarded to prevent wasting resources on useless blocks from faulty
+// peers.
+func TestDistantAnnouncementDiscarding62(t *testing.T) { testDistantAnnouncementDiscarding(t, 62) }
+func TestDistantAnnouncementDiscarding63(t *testing.T) { testDistantAnnouncementDiscarding(t, 63) }
+func TestDistantAnnouncementDiscarding64(t *testing.T) { testDistantAnnouncementDiscarding(t, 64) }
+
+func testDistantAnnouncementDiscarding(t *testing.T, protocol int) {
+	// Create a long chain to import and define the discard boundaries
+	hashes, blocks := makeChain(3*maxQueueDist, 0, genesis)
+	head := hashes[len(hashes)/2]
+
+	low, high := len(hashes)/2+maxUncleDist+1, len(hashes)/2-maxQueueDist-1
+
+	// Create a tester and simulate a head block being the middle of the above chain
+	tester := newTester()
+	tester.hashes = []common.Hash{head}
+	tester.blocks = map[common.Hash]*types.Block{head: blocks[head]}
+
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
+
+	fetching := make(chan struct{}, 2)
+	tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- struct{}{} }
+
+	// Ensure that a block with a lower number than the threshold is discarded
+	tester.fetcher.Notify("lower", hashes[low], blocks[hashes[low]].NumberU64(), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	select {
+	case <-time.After(50 * time.Millisecond):
+	case <-fetching:
+		t.Fatalf("fetcher requested stale header")
+	}
+	// Ensure that a block with a higher number than the threshold is discarded
+	tester.fetcher.Notify("higher", hashes[high], blocks[hashes[high]].NumberU64(), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	select {
+	case <-time.After(50 * time.Millisecond):
+	case <-fetching:
+		t.Fatalf("fetcher requested future header")
+	}
+}
+
+// Tests that peers announcing blocks with invalid numbers (i.e. not matching
+// the headers provided afterwards) get dropped as malicious.
+func TestInvalidNumberAnnouncement62(t *testing.T) { testInvalidNumberAnnouncement(t, 62) }
+func TestInvalidNumberAnnouncement63(t *testing.T) { testInvalidNumberAnnouncement(t, 63) }
+func TestInvalidNumberAnnouncement64(t *testing.T) { testInvalidNumberAnnouncement(t, 64) }
+
+func testInvalidNumberAnnouncement(t *testing.T, protocol int) {
+	// Create a single block to import and check numbers against
+	hashes, blocks := makeChain(1, 0, genesis)
+
+	tester := newTester()
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
+
+	imported := make(chan *types.Block)
+	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+	// Announce a block with a bad number, check for immediate drop
+	tester.fetcher.Notify("bad", hashes[0], 2, time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	verifyImportEvent(t, imported, false)
+
+	if !tester.drops["bad"] {
+		t.Fatalf("peer with invalid numbered announcement not dropped")
+	}
+	// Make sure a good announcement passes without a drop
+	tester.fetcher.Notify("good", hashes[0], 1, time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+	verifyImportEvent(t, imported, true)
+
+	if tester.drops["good"] {
+		t.Fatalf("peer with valid numbered announcement dropped")
+	}
+	verifyImportDone(t, imported)
+}
+
+// Tests that if a block is empty (i.e. header only), no body request should be
+// made, and instead the header should be assembled into a whole block in itself.
+func TestEmptyBlockShortCircuit62(t *testing.T) { testEmptyBlockShortCircuit(t, 62) }
+func TestEmptyBlockShortCircuit63(t *testing.T) { testEmptyBlockShortCircuit(t, 63) }
+func TestEmptyBlockShortCircuit64(t *testing.T) { testEmptyBlockShortCircuit(t, 64) }
+
+func testEmptyBlockShortCircuit(t *testing.T, protocol int) {
+	// Create a chain of blocks to import
+	hashes, blocks := makeChain(32, 0, genesis)
+
+	tester := newTester()
+	headerFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	bodyFetcher := tester.makeBodyFetcher(blocks, 0)
+
+	// Add a monitoring hook for all internal events
+	fetching := make(chan []common.Hash)
+	tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- hashes }
+
+	completing := make(chan []common.Hash)
+	tester.fetcher.completingHook = func(hashes []common.Hash) { completing <- hashes }
+
+	imported := make(chan *types.Block)
+	tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+	// Iteratively announce blocks until all are imported
+	for i := len(hashes) - 2; i >= 0; i-- {
+		tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, headerFetcher, bodyFetcher)
+
+		// All announces should fetch the header
+		verifyFetchingEvent(t, fetching, true)
+
+		// Only blocks with data contents should request bodies
+		verifyCompletingEvent(t, completing, len(blocks[hashes[i]].Transactions()) > 0 || len(blocks[hashes[i]].Uncles()) > 0)
+
+		// Irrelevant of the construct, import should succeed
+		verifyImportEvent(t, imported, true)
+	}
+	verifyImportDone(t, imported)
+}
+
 // Tests that a peer is unable to use unbounded memory with sending infinite
 // block announcements to a node, but that even in the face of such an attack,
 // the fetcher remains operational.
-func TestHashMemoryExhaustionAttack(t *testing.T) {
+func TestHashMemoryExhaustionAttack61(t *testing.T) { testHashMemoryExhaustionAttack(t, 61) }
+func TestHashMemoryExhaustionAttack62(t *testing.T) { testHashMemoryExhaustionAttack(t, 62) }
+func TestHashMemoryExhaustionAttack63(t *testing.T) { testHashMemoryExhaustionAttack(t, 63) }
+func TestHashMemoryExhaustionAttack64(t *testing.T) { testHashMemoryExhaustionAttack(t, 64) }
+
+func testHashMemoryExhaustionAttack(t *testing.T, protocol int) {
 	// Create a tester with instrumented import hooks
 	tester := newTester()
 
@@ -429,17 +758,29 @@ func TestHashMemoryExhaustionAttack(t *testing.T) {
 	// Create a valid chain and an infinite junk chain
 	targetBlocks := hashLimit + 2*maxQueueDist
 	hashes, blocks := makeChain(targetBlocks, 0, genesis)
-	valid := tester.makeFetcher(blocks)
+	validBlockFetcher := tester.makeBlockFetcher(blocks)
+	validHeaderFetcher := tester.makeHeaderFetcher(blocks, -gatherSlack)
+	validBodyFetcher := tester.makeBodyFetcher(blocks, 0)
 
 	attack, _ := makeChain(targetBlocks, 0, unknownBlock)
-	attacker := tester.makeFetcher(nil)
+	attackerBlockFetcher := tester.makeBlockFetcher(nil)
+	attackerHeaderFetcher := tester.makeHeaderFetcher(nil, -gatherSlack)
+	attackerBodyFetcher := tester.makeBodyFetcher(nil, 0)
 
 	// Feed the tester a huge hashset from the attacker, and a limited from the valid peer
 	for i := 0; i < len(attack); i++ {
 		if i < maxQueueDist {
-			tester.fetcher.Notify("valid", hashes[len(hashes)-2-i], time.Now(), valid)
+			if protocol < 62 {
+				tester.fetcher.Notify("valid", hashes[len(hashes)-2-i], 0, time.Now(), validBlockFetcher, nil, nil)
+			} else {
+				tester.fetcher.Notify("valid", hashes[len(hashes)-2-i], uint64(i+1), time.Now(), nil, validHeaderFetcher, validBodyFetcher)
+			}
+		}
+		if protocol < 62 {
+			tester.fetcher.Notify("attacker", attack[i], 0, time.Now(), attackerBlockFetcher, nil, nil)
+		} else {
+			tester.fetcher.Notify("attacker", attack[i], 1 /* don't distance drop */, time.Now(), nil, attackerHeaderFetcher, attackerBodyFetcher)
 		}
-		tester.fetcher.Notify("attacker", attack[i], time.Now(), attacker)
 	}
 	if len(tester.fetcher.announced) != hashLimit+maxQueueDist {
 		t.Fatalf("queued announce count mismatch: have %d, want %d", len(tester.fetcher.announced), hashLimit+maxQueueDist)
@@ -449,8 +790,12 @@ func TestHashMemoryExhaustionAttack(t *testing.T) {
 
 	// Feed the remaining valid hashes to ensure DOS protection state remains clean
 	for i := len(hashes) - maxQueueDist - 2; i >= 0; i-- {
-		tester.fetcher.Notify("valid", hashes[i], time.Now().Add(-arriveTimeout), valid)
-		verifyImportEvent(t, imported)
+		if protocol < 62 {
+			tester.fetcher.Notify("valid", hashes[i], 0, time.Now().Add(-arriveTimeout), validBlockFetcher, nil, nil)
+		} else {
+			tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), nil, validHeaderFetcher, validBodyFetcher)
+		}
+		verifyImportEvent(t, imported, true)
 	}
 	verifyImportDone(t, imported)
 }
@@ -498,7 +843,7 @@ func TestBlockMemoryExhaustionAttack(t *testing.T) {
 	// Insert the remaining blocks in chunks to ensure clean DOS protection
 	for i := maxQueueDist; i < len(hashes)-1; i++ {
 		tester.fetcher.Enqueue("valid", blocks[hashes[len(hashes)-2-i]])
-		verifyImportEvent(t, imported)
+		verifyImportEvent(t, imported, true)
 	}
 	verifyImportDone(t, imported)
 }
diff --git a/eth/fetcher/metrics.go b/eth/fetcher/metrics.go
index 76cc49226..b82d3ca01 100644
--- a/eth/fetcher/metrics.go
+++ b/eth/fetcher/metrics.go
@@ -23,10 +23,24 @@ import (
 )
 
 var (
-	announceMeter  = metrics.NewMeter("eth/sync/RemoteAnnounces")
-	announceTimer  = metrics.NewTimer("eth/sync/LocalAnnounces")
-	broadcastMeter = metrics.NewMeter("eth/sync/RemoteBroadcasts")
-	broadcastTimer = metrics.NewTimer("eth/sync/LocalBroadcasts")
-	discardMeter   = metrics.NewMeter("eth/sync/DiscardedBlocks")
-	futureMeter    = metrics.NewMeter("eth/sync/FutureBlocks")
+	propAnnounceInMeter   = metrics.NewMeter("eth/fetcher/prop/announces/in")
+	propAnnounceOutTimer  = metrics.NewTimer("eth/fetcher/prop/announces/out")
+	propAnnounceDropMeter = metrics.NewMeter("eth/fetcher/prop/announces/drop")
+	propAnnounceDOSMeter  = metrics.NewMeter("eth/fetcher/prop/announces/dos")
+
+	propBroadcastInMeter   = metrics.NewMeter("eth/fetcher/prop/broadcasts/in")
+	propBroadcastOutTimer  = metrics.NewTimer("eth/fetcher/prop/broadcasts/out")
+	propBroadcastDropMeter = metrics.NewMeter("eth/fetcher/prop/broadcasts/drop")
+	propBroadcastDOSMeter  = metrics.NewMeter("eth/fetcher/prop/broadcasts/dos")
+
+	blockFetchMeter  = metrics.NewMeter("eth/fetcher/fetch/blocks")
+	headerFetchMeter = metrics.NewMeter("eth/fetcher/fetch/headers")
+	bodyFetchMeter   = metrics.NewMeter("eth/fetcher/fetch/bodies")
+
+	blockFilterInMeter   = metrics.NewMeter("eth/fetcher/filter/blocks/in")
+	blockFilterOutMeter  = metrics.NewMeter("eth/fetcher/filter/blocks/out")
+	headerFilterInMeter  = metrics.NewMeter("eth/fetcher/filter/headers/in")
+	headerFilterOutMeter = metrics.NewMeter("eth/fetcher/filter/headers/out")
+	bodyFilterInMeter    = metrics.NewMeter("eth/fetcher/filter/bodies/in")
+	bodyFilterOutMeter   = metrics.NewMeter("eth/fetcher/filter/bodies/out")
 )
diff --git a/eth/handler.go b/eth/handler.go
index 4f3d1f34c..f22afecb7 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -36,10 +36,8 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-// This is the target maximum size of returned blocks for the
-// getBlocks message. The reply message may exceed it
-// if a single block is larger than the limit.
-const maxBlockRespSize = 2 * 1024 * 1024
+// This is the target maximum size of returned blocks, headers or node data.
+const softResponseLimit = 2 * 1024 * 1024
 
 func errResp(code errCode, format string, v ...interface{}) error {
 	return fmt.Errorf("%v - %v", code, fmt.Sprintf(format, v...))
@@ -59,12 +57,13 @@ func (ep extProt) GetHashes(hash common.Hash) error    { return ep.getHashes(has
 func (ep extProt) GetBlock(hashes []common.Hash) error { return ep.getBlocks(hashes) }
 
 type ProtocolManager struct {
-	protVer, netId int
-	txpool         txPool
-	chainman       *core.ChainManager
-	downloader     *downloader.Downloader
-	fetcher        *fetcher.Fetcher
-	peers          *peerSet
+	txpool   txPool
+	chainman *core.ChainManager
+	chaindb  common.Database
+
+	downloader *downloader.Downloader
+	fetcher    *fetcher.Fetcher
+	peers      *peerSet
 
 	SubProtocols []p2p.Protocol
 
@@ -85,17 +84,17 @@ type ProtocolManager struct {
 
 // NewProtocolManager returns a new ethereum sub protocol manager. The Ethereum sub protocol manages peers capable
 // with the ethereum network.
-func NewProtocolManager(networkId int, mux *event.TypeMux, txpool txPool, pow pow.PoW, chainman *core.ChainManager) *ProtocolManager {
+func NewProtocolManager(networkId int, mux *event.TypeMux, txpool txPool, pow pow.PoW, chainman *core.ChainManager, chaindb common.Database) *ProtocolManager {
 	// Create the protocol manager with the base fields
 	manager := &ProtocolManager{
 		eventMux:  mux,
 		txpool:    txpool,
 		chainman:  chainman,
+		chaindb:   chaindb,
 		peers:     newPeerSet(),
 		newPeerCh: make(chan *peer, 1),
 		txsyncCh:  make(chan *txsync),
 		quitSync:  make(chan struct{}),
-		netId:     networkId,
 	}
 	// Initiate a sub-protocol for every implemented version we can handle
 	manager.SubProtocols = make([]p2p.Protocol, len(ProtocolVersions))
@@ -176,7 +175,7 @@ func (pm *ProtocolManager) Stop() {
 }
 
 func (pm *ProtocolManager) newPeer(pv, nv int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
-	return newPeer(pv, nv, p, rw)
+	return newPeer(pv, nv, p, newMeteredMsgWriter(rw))
 }
 
 // handle is the callback invoked to manage the life cycle of an eth peer. When
@@ -190,6 +189,9 @@ func (pm *ProtocolManager) handle(p *peer) error {
 		glog.V(logger.Debug).Infof("%v: handshake failed: %v", p, err)
 		return err
 	}
+	if rw, ok := p.rw.(*meteredMsgReadWriter); ok {
+		rw.Init(p.version)
+	}
 	// Register the peer locally
 	glog.V(logger.Detail).Infof("%v: adding peer", p)
 	if err := pm.peers.Register(p); err != nil {
@@ -199,7 +201,9 @@ func (pm *ProtocolManager) handle(p *peer) error {
 	defer pm.removePeer(p.id)
 
 	// Register the peer in the downloader. If the downloader considers it banned, we disconnect
-	if err := pm.downloader.RegisterPeer(p.id, p.version, p.Head(), p.RequestHashes, p.RequestHashesFromNumber, p.RequestBlocks); err != nil {
+	if err := pm.downloader.RegisterPeer(p.id, p.version, p.Head(),
+		p.RequestHashes, p.RequestHashesFromNumber, p.RequestBlocks,
+		p.RequestHeadersByHash, p.RequestHeadersByNumber, p.RequestBodies); err != nil {
 		return err
 	}
 	// Propagate existing transactions. new transactions appearing
@@ -230,12 +234,12 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 	defer msg.Discard()
 
 	// Handle the message depending on its contents
-	switch msg.Code {
-	case StatusMsg:
+	switch {
+	case msg.Code == StatusMsg:
 		// Status messages should never arrive after the handshake
 		return errResp(ErrExtraStatusMsg, "uncontrolled status message")
 
-	case GetBlockHashesMsg:
+	case p.version < eth62 && msg.Code == GetBlockHashesMsg:
 		// Retrieve the number of hashes to return and from which origin hash
 		var request getBlockHashesData
 		if err := msg.Decode(&request); err != nil {
@@ -251,7 +255,7 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		}
 		return p.SendBlockHashes(hashes)
 
-	case GetBlockHashesFromNumberMsg:
+	case p.version < eth62 && msg.Code == GetBlockHashesFromNumberMsg:
 		// Retrieve and decode the number of hashes to return and from which origin number
 		var request getBlockHashesFromNumberData
 		if err := msg.Decode(&request); err != nil {
@@ -278,24 +282,19 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		}
 		return p.SendBlockHashes(hashes)
 
-	case BlockHashesMsg:
+	case p.version < eth62 && msg.Code == BlockHashesMsg:
 		// A batch of hashes arrived to one of our previous requests
-		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
-		reqHashInPacketsMeter.Mark(1)
-
 		var hashes []common.Hash
-		if err := msgStream.Decode(&hashes); err != nil {
+		if err := msg.Decode(&hashes); err != nil {
 			break
 		}
-		reqHashInTrafficMeter.Mark(int64(32 * len(hashes)))
-
 		// Deliver them all to the downloader for queuing
-		err := pm.downloader.DeliverHashes(p.id, hashes)
+		err := pm.downloader.DeliverHashes61(p.id, hashes)
 		if err != nil {
 			glog.V(logger.Debug).Infoln(err)
 		}
 
-	case GetBlocksMsg:
+	case p.version < eth62 && msg.Code == GetBlocksMsg:
 		// Decode the retrieval message
 		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
 		if _, err := msgStream.List(); err != nil {
@@ -305,94 +304,279 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		var (
 			hash   common.Hash
 			bytes  common.StorageSize
-			hashes []common.Hash
 			blocks []*types.Block
 		)
-		for {
+		for len(blocks) < downloader.MaxBlockFetch && bytes < softResponseLimit {
+			//Retrieve the hash of the next block
 			err := msgStream.Decode(&hash)
 			if err == rlp.EOL {
 				break
 			} else if err != nil {
 				return errResp(ErrDecode, "msg %v: %v", msg, err)
 			}
-			hashes = append(hashes, hash)
-
 			// Retrieve the requested block, stopping if enough was found
 			if block := pm.chainman.GetBlock(hash); block != nil {
 				blocks = append(blocks, block)
 				bytes += block.Size()
-				if len(blocks) >= downloader.MaxBlockFetch || bytes > maxBlockRespSize {
-					break
-				}
 			}
 		}
-		if glog.V(logger.Detail) && len(blocks) == 0 && len(hashes) > 0 {
-			list := "["
-			for _, hash := range hashes {
-				list += fmt.Sprintf("%x, ", hash[:4])
-			}
-			list = list[:len(list)-2] + "]"
-
-			glog.Infof("%v: no blocks found for requested hashes %s", p, list)
-		}
 		return p.SendBlocks(blocks)
 
-	case BlocksMsg:
+	case p.version < eth62 && msg.Code == BlocksMsg:
 		// Decode the arrived block message
-		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
-		reqBlockInPacketsMeter.Mark(1)
-
 		var blocks []*types.Block
-		if err := msgStream.Decode(&blocks); err != nil {
+		if err := msg.Decode(&blocks); err != nil {
 			glog.V(logger.Detail).Infoln("Decode error", err)
 			blocks = nil
 		}
 		// Update the receive timestamp of each block
 		for _, block := range blocks {
-			reqBlockInTrafficMeter.Mark(block.Size().Int64())
 			block.ReceivedAt = msg.ReceivedAt
 		}
 		// Filter out any explicitly requested blocks, deliver the rest to the downloader
-		if blocks := pm.fetcher.Filter(blocks); len(blocks) > 0 {
-			pm.downloader.DeliverBlocks(p.id, blocks)
+		if blocks := pm.fetcher.FilterBlocks(blocks); len(blocks) > 0 {
+			pm.downloader.DeliverBlocks61(p.id, blocks)
 		}
 
-	case NewBlockHashesMsg:
-		// Retrieve and deseralize the remote new block hashes notification
+	// Block header query, collect the requested headers and reply
+	case p.version >= eth62 && msg.Code == GetBlockHeadersMsg:
+		// Decode the complex header query
+		var query getBlockHeadersData
+		if err := msg.Decode(&query); err != nil {
+			return errResp(ErrDecode, "%v: %v", msg, err)
+		}
+		// Gather blocks until the fetch or network limits is reached
+		var (
+			bytes   common.StorageSize
+			headers []*types.Header
+			unknown bool
+		)
+		for !unknown && len(headers) < int(query.Amount) && bytes < softResponseLimit && len(headers) < downloader.MaxHeaderFetch {
+			// Retrieve the next block satisfying the query
+			var origin *types.Block
+			if query.Origin.Hash != (common.Hash{}) {
+				origin = pm.chainman.GetBlock(query.Origin.Hash)
+			} else {
+				origin = pm.chainman.GetBlockByNumber(query.Origin.Number)
+			}
+			if origin == nil {
+				break
+			}
+			headers = append(headers, origin.Header())
+			bytes += origin.Size()
+
+			// Advance to the next block of the query
+			switch {
+			case query.Origin.Hash != (common.Hash{}) && query.Reverse:
+				// Hash based traversal towards the genesis block
+				for i := 0; i < int(query.Skip)+1; i++ {
+					if block := pm.chainman.GetBlock(query.Origin.Hash); block != nil {
+						query.Origin.Hash = block.ParentHash()
+					} else {
+						unknown = true
+						break
+					}
+				}
+			case query.Origin.Hash != (common.Hash{}) && !query.Reverse:
+				// Hash based traversal towards the leaf block
+				if block := pm.chainman.GetBlockByNumber(origin.NumberU64() + query.Skip + 1); block != nil {
+					if pm.chainman.GetBlockHashesFromHash(block.Hash(), query.Skip+1)[query.Skip] == query.Origin.Hash {
+						query.Origin.Hash = block.Hash()
+					} else {
+						unknown = true
+					}
+				} else {
+					unknown = true
+				}
+			case query.Reverse:
+				// Number based traversal towards the genesis block
+				if query.Origin.Number >= query.Skip+1 {
+					query.Origin.Number -= (query.Skip + 1)
+				} else {
+					unknown = true
+				}
+
+			case !query.Reverse:
+				// Number based traversal towards the leaf block
+				query.Origin.Number += (query.Skip + 1)
+			}
+		}
+		return p.SendBlockHeaders(headers)
+
+	case p.version >= eth62 && msg.Code == BlockHeadersMsg:
+		// A batch of headers arrived to one of our previous requests
+		var headers []*types.Header
+		if err := msg.Decode(&headers); err != nil {
+			return errResp(ErrDecode, "msg %v: %v", msg, err)
+		}
+		// Filter out any explicitly requested headers, deliver the rest to the downloader
+		filter := len(headers) == 1
+		if filter {
+			headers = pm.fetcher.FilterHeaders(headers, time.Now())
+		}
+		if len(headers) > 0 || !filter {
+			err := pm.downloader.DeliverHeaders(p.id, headers)
+			if err != nil {
+				glog.V(logger.Debug).Infoln(err)
+			}
+		}
+
+	case p.version >= eth62 && msg.Code == BlockBodiesMsg:
+		// A batch of block bodies arrived to one of our previous requests
+		var request blockBodiesData
+		if err := msg.Decode(&request); err != nil {
+			return errResp(ErrDecode, "msg %v: %v", msg, err)
+		}
+		// Deliver them all to the downloader for queuing
+		trasactions := make([][]*types.Transaction, len(request))
+		uncles := make([][]*types.Header, len(request))
+
+		for i, body := range request {
+			trasactions[i] = body.Transactions
+			uncles[i] = body.Uncles
+		}
+		// Filter out any explicitly requested bodies, deliver the rest to the downloader
+		if trasactions, uncles := pm.fetcher.FilterBodies(trasactions, uncles, time.Now()); len(trasactions) > 0 || len(uncles) > 0 {
+			err := pm.downloader.DeliverBodies(p.id, trasactions, uncles)
+			if err != nil {
+				glog.V(logger.Debug).Infoln(err)
+			}
+		}
+
+	case p.version >= eth62 && msg.Code == GetBlockBodiesMsg:
+		// Decode the retrieval message
 		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
+		if _, err := msgStream.List(); err != nil {
+			return err
+		}
+		// Gather blocks until the fetch or network limits is reached
+		var (
+			hash   common.Hash
+			bytes  common.StorageSize
+			bodies []*blockBody
+		)
+		for bytes < softResponseLimit && len(bodies) < downloader.MaxBlockFetch {
+			//Retrieve the hash of the next block
+			if err := msgStream.Decode(&hash); err == rlp.EOL {
+				break
+			} else if err != nil {
+				return errResp(ErrDecode, "msg %v: %v", msg, err)
+			}
+			// Retrieve the requested block, stopping if enough was found
+			if block := pm.chainman.GetBlock(hash); block != nil {
+				bodies = append(bodies, &blockBody{Transactions: block.Transactions(), Uncles: block.Uncles()})
+				bytes += block.Size()
+			}
+		}
+		return p.SendBlockBodies(bodies)
 
-		var hashes []common.Hash
-		if err := msgStream.Decode(&hashes); err != nil {
-			break
+	case p.version >= eth63 && msg.Code == GetNodeDataMsg:
+		// Decode the retrieval message
+		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
+		if _, err := msgStream.List(); err != nil {
+			return err
 		}
-		propHashInPacketsMeter.Mark(1)
-		propHashInTrafficMeter.Mark(int64(32 * len(hashes)))
+		// Gather state data until the fetch or network limits is reached
+		var (
+			hash  common.Hash
+			bytes int
+			data  [][]byte
+		)
+		for bytes < softResponseLimit && len(data) < downloader.MaxStateFetch {
+			// Retrieve the hash of the next state entry
+			if err := msgStream.Decode(&hash); err == rlp.EOL {
+				break
+			} else if err != nil {
+				return errResp(ErrDecode, "msg %v: %v", msg, err)
+			}
+			// Retrieve the requested state entry, stopping if enough was found
+			if entry, err := pm.chaindb.Get(hash.Bytes()); err == nil {
+				data = append(data, entry)
+				bytes += len(entry)
+			}
+		}
+		return p.SendNodeData(data)
 
+	case p.version >= eth63 && msg.Code == GetReceiptsMsg:
+		// Decode the retrieval message
+		msgStream := rlp.NewStream(msg.Payload, uint64(msg.Size))
+		if _, err := msgStream.List(); err != nil {
+			return err
+		}
+		// Gather state data until the fetch or network limits is reached
+		var (
+			hash     common.Hash
+			bytes    int
+			receipts []*types.Receipt
+		)
+		for bytes < softResponseLimit && len(receipts) < downloader.MaxReceiptsFetch {
+			// Retrieve the hash of the next transaction receipt
+			if err := msgStream.Decode(&hash); err == rlp.EOL {
+				break
+			} else if err != nil {
+				return errResp(ErrDecode, "msg %v: %v", msg, err)
+			}
+			// Retrieve the requested receipt, stopping if enough was found
+			if receipt := core.GetReceipt(pm.chaindb, hash); receipt != nil {
+				receipts = append(receipts, receipt)
+				bytes += len(receipt.RlpEncode())
+			}
+		}
+		return p.SendReceipts(receipts)
+
+	case msg.Code == NewBlockHashesMsg:
+		// Retrieve and deseralize the remote new block hashes notification
+		type announce struct {
+			Hash   common.Hash
+			Number uint64
+		}
+		var announces = []announce{}
+
+		if p.version < eth62 {
+			// We're running the old protocol, make block number unknown (0)
+			var hashes []common.Hash
+			if err := msg.Decode(&hashes); err != nil {
+				return errResp(ErrDecode, "%v: %v", msg, err)
+			}
+			for _, hash := range hashes {
+				announces = append(announces, announce{hash, 0})
+			}
+		} else {
+			// Otherwise extract both block hash and number
+			var request newBlockHashesData
+			if err := msg.Decode(&request); err != nil {
+				return errResp(ErrDecode, "%v: %v", msg, err)
+			}
+			for _, block := range request {
+				announces = append(announces, announce{block.Hash, block.Number})
+			}
+		}
 		// Mark the hashes as present at the remote node
-		for _, hash := range hashes {
-			p.MarkBlock(hash)
-			p.SetHead(hash)
+		for _, block := range announces {
+			p.MarkBlock(block.Hash)
+			p.SetHead(block.Hash)
 		}
 		// Schedule all the unknown hashes for retrieval
-		unknown := make([]common.Hash, 0, len(hashes))
-		for _, hash := range hashes {
-			if !pm.chainman.HasBlock(hash) {
-				unknown = append(unknown, hash)
+		unknown := make([]announce, 0, len(announces))
+		for _, block := range announces {
+			if !pm.chainman.HasBlock(block.Hash) {
+				unknown = append(unknown, block)
 			}
 		}
-		for _, hash := range unknown {
-			pm.fetcher.Notify(p.id, hash, time.Now(), p.RequestBlocks)
+		for _, block := range unknown {
+			if p.version < eth62 {
+				pm.fetcher.Notify(p.id, block.Hash, block.Number, time.Now(), p.RequestBlocks, nil, nil)
+			} else {
+				pm.fetcher.Notify(p.id, block.Hash, block.Number, time.Now(), nil, p.RequestOneHeader, p.RequestBodies)
+			}
 		}
 
-	case NewBlockMsg:
+	case msg.Code == NewBlockMsg:
 		// Retrieve and decode the propagated block
 		var request newBlockData
 		if err := msg.Decode(&request); err != nil {
 			return errResp(ErrDecode, "%v: %v", msg, err)
 		}
-		propBlockInPacketsMeter.Mark(1)
-		propBlockInTrafficMeter.Mark(request.Block.Size().Int64())
-
 		if err := request.Block.ValidateFields(); err != nil {
 			return errResp(ErrDecode, "block validation %v: %v", msg, err)
 		}
@@ -421,13 +605,12 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 			}
 		}
 
-	case TxMsg:
+	case msg.Code == TxMsg:
 		// Transactions arrived, parse all of them and deliver to the pool
 		var txs []*types.Transaction
 		if err := msg.Decode(&txs); err != nil {
 			return errResp(ErrDecode, "msg %v: %v", msg, err)
 		}
-		propTxnInPacketsMeter.Mark(1)
 		for i, tx := range txs {
 			// Validate and mark the remote transaction
 			if tx == nil {
@@ -436,7 +619,6 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 			p.MarkTransaction(tx.Hash())
 
 			// Log it's arrival for later analysis
-			propTxnInTrafficMeter.Mark(tx.Size().Int64())
 			jsonlogger.LogJson(&logger.EthTxReceived{
 				TxHash:   tx.Hash().Hex(),
 				RemoteId: p.ID().String(),
@@ -476,7 +658,11 @@ func (pm *ProtocolManager) BroadcastBlock(block *types.Block, propagate bool) {
 	// Otherwise if the block is indeed in out own chain, announce it
 	if pm.chainman.HasBlock(hash) {
 		for _, peer := range peers {
-			peer.SendNewBlockHashes([]common.Hash{hash})
+			if peer.version < eth62 {
+				peer.SendNewBlockHashes61([]common.Hash{hash})
+			} else {
+				peer.SendNewBlockHashes([]common.Hash{hash}, []uint64{block.NumberU64()})
+			}
 		}
 		glog.V(logger.Detail).Infof("announced block %x to %d peers in %v", hash[:4], len(peers), time.Since(block.ReceivedAt))
 	}
diff --git a/eth/handler_test.go b/eth/handler_test.go
new file mode 100644
index 000000000..6400d4e78
--- /dev/null
+++ b/eth/handler_test.go
@@ -0,0 +1,522 @@
+package eth
+
+import (
+	"fmt"
+	"math/big"
+	"math/rand"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/eth/downloader"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/p2p"
+	"github.com/ethereum/go-ethereum/params"
+)
+
+// Tests that hashes can be retrieved from a remote chain by hashes in reverse
+// order.
+func TestGetBlockHashes61(t *testing.T) { testGetBlockHashes(t, 61) }
+
+func testGetBlockHashes(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(downloader.MaxHashFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a batch of tests for various scenarios
+	limit := downloader.MaxHashFetch
+	tests := []struct {
+		origin common.Hash
+		number int
+		result int
+	}{
+		{common.Hash{}, 1, 0},                                 // Make sure non existent hashes don't return results
+		{pm.chainman.Genesis().Hash(), 1, 0},                  // There are no hashes to retrieve up from the genesis
+		{pm.chainman.GetBlockByNumber(5).Hash(), 5, 5},        // All the hashes including the genesis requested
+		{pm.chainman.GetBlockByNumber(5).Hash(), 10, 5},       // More hashes than available till the genesis requested
+		{pm.chainman.GetBlockByNumber(100).Hash(), 10, 10},    // All hashes available from the middle of the chain
+		{pm.chainman.CurrentBlock().Hash(), 10, 10},           // All hashes available from the head of the chain
+		{pm.chainman.CurrentBlock().Hash(), limit, limit},     // Request the maximum allowed hash count
+		{pm.chainman.CurrentBlock().Hash(), limit + 1, limit}, // Request more than the maximum allowed hash count
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Assemble the hash response we would like to receive
+		resp := make([]common.Hash, tt.result)
+		if len(resp) > 0 {
+			from := pm.chainman.GetBlock(tt.origin).NumberU64() - 1
+			for j := 0; j < len(resp); j++ {
+				resp[j] = pm.chainman.GetBlockByNumber(uint64(int(from) - j)).Hash()
+			}
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x03, getBlockHashesData{tt.origin, uint64(tt.number)})
+		if err := p2p.ExpectMsg(peer.app, 0x04, resp); err != nil {
+			t.Errorf("test %d: block hashes mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that hashes can be retrieved from a remote chain by numbers in forward
+// order.
+func TestGetBlockHashesFromNumber61(t *testing.T) { testGetBlockHashesFromNumber(t, 61) }
+
+func testGetBlockHashesFromNumber(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(downloader.MaxHashFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a batch of tests for various scenarios
+	limit := downloader.MaxHashFetch
+	tests := []struct {
+		origin uint64
+		number int
+		result int
+	}{
+		{pm.chainman.CurrentBlock().NumberU64() + 1, 1, 0},     // Out of bounds requests should return empty
+		{pm.chainman.CurrentBlock().NumberU64(), 1, 1},         // Make sure the head hash can be retrieved
+		{pm.chainman.CurrentBlock().NumberU64() - 4, 5, 5},     // All hashes, including the head hash requested
+		{pm.chainman.CurrentBlock().NumberU64() - 4, 10, 5},    // More hashes requested than available till the head
+		{pm.chainman.CurrentBlock().NumberU64() - 100, 10, 10}, // All hashes available from the middle of the chain
+		{0, 10, 10},           // All hashes available from the root of the chain
+		{0, limit, limit},     // Request the maximum allowed hash count
+		{0, limit + 1, limit}, // Request more than the maximum allowed hash count
+		{0, 1, 1},             // Make sure the genesis hash can be retrieved
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Assemble the hash response we would like to receive
+		resp := make([]common.Hash, tt.result)
+		for j := 0; j < len(resp); j++ {
+			resp[j] = pm.chainman.GetBlockByNumber(tt.origin + uint64(j)).Hash()
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x08, getBlockHashesFromNumberData{tt.origin, uint64(tt.number)})
+		if err := p2p.ExpectMsg(peer.app, 0x04, resp); err != nil {
+			t.Errorf("test %d: block hashes mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that blocks can be retrieved from a remote chain based on their hashes.
+func TestGetBlocks61(t *testing.T) { testGetBlocks(t, 61) }
+
+func testGetBlocks(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(downloader.MaxHashFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a batch of tests for various scenarios
+	limit := downloader.MaxBlockFetch
+	tests := []struct {
+		random    int           // Number of blocks to fetch randomly from the chain
+		explicit  []common.Hash // Explicitly requested blocks
+		available []bool        // Availability of explicitly requested blocks
+		expected  int           // Total number of existing blocks to expect
+	}{
+		{1, nil, nil, 1},                                                       // A single random block should be retrievable
+		{10, nil, nil, 10},                                                     // Multiple random blocks should be retrievable
+		{limit, nil, nil, limit},                                               // The maximum possible blocks should be retrievable
+		{limit + 1, nil, nil, limit},                                           // No more that the possible block count should be returned
+		{0, []common.Hash{pm.chainman.Genesis().Hash()}, []bool{true}, 1},      // The genesis block should be retrievable
+		{0, []common.Hash{pm.chainman.CurrentBlock().Hash()}, []bool{true}, 1}, // The chains head block should be retrievable
+		{0, []common.Hash{common.Hash{}}, []bool{false}, 0},                    // A non existent block should not be returned
+
+		// Existing and non-existing blocks interleaved should not cause problems
+		{0, []common.Hash{
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(1).Hash(),
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(10).Hash(),
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(100).Hash(),
+			common.Hash{},
+		}, []bool{false, true, false, true, false, true, false}, 3},
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Collect the hashes to request, and the response to expect
+		hashes, seen := []common.Hash{}, make(map[int64]bool)
+		blocks := []*types.Block{}
+
+		for j := 0; j < tt.random; j++ {
+			for {
+				num := rand.Int63n(int64(pm.chainman.CurrentBlock().NumberU64()))
+				if !seen[num] {
+					seen[num] = true
+
+					block := pm.chainman.GetBlockByNumber(uint64(num))
+					hashes = append(hashes, block.Hash())
+					if len(blocks) < tt.expected {
+						blocks = append(blocks, block)
+					}
+					break
+				}
+			}
+		}
+		for j, hash := range tt.explicit {
+			hashes = append(hashes, hash)
+			if tt.available[j] && len(blocks) < tt.expected {
+				blocks = append(blocks, pm.chainman.GetBlock(hash))
+			}
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x05, hashes)
+		if err := p2p.ExpectMsg(peer.app, 0x06, blocks); err != nil {
+			t.Errorf("test %d: blocks mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that block headers can be retrieved from a remote chain based on user queries.
+func TestGetBlockHeaders62(t *testing.T) { testGetBlockHeaders(t, 62) }
+func TestGetBlockHeaders63(t *testing.T) { testGetBlockHeaders(t, 63) }
+func TestGetBlockHeaders64(t *testing.T) { testGetBlockHeaders(t, 64) }
+
+func testGetBlockHeaders(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(downloader.MaxHashFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a "random" unknown hash for testing
+	var unknown common.Hash
+	for i, _ := range unknown {
+		unknown[i] = byte(i)
+	}
+	// Create a batch of tests for various scenarios
+	limit := uint64(downloader.MaxHeaderFetch)
+	tests := []struct {
+		query  *getBlockHeadersData // The query to execute for header retrieval
+		expect []common.Hash        // The hashes of the block whose headers are expected
+	}{
+		// A single random block should be retrievable by hash and number too
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: pm.chainman.GetBlockByNumber(limit / 2).Hash()}, Amount: 1},
+			[]common.Hash{pm.chainman.GetBlockByNumber(limit / 2).Hash()},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 1},
+			[]common.Hash{pm.chainman.GetBlockByNumber(limit / 2).Hash()},
+		},
+		// Multiple headers should be retrievable in both directions
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 3},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(limit / 2).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 + 1).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 + 2).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(limit / 2).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 - 1).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 - 2).Hash(),
+			},
+		},
+		// Multiple headers with skip lists should be retrievable
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Skip: 3, Amount: 3},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(limit / 2).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 + 4).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 + 8).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Skip: 3, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(limit / 2).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 - 4).Hash(),
+				pm.chainman.GetBlockByNumber(limit/2 - 8).Hash(),
+			},
+		},
+		// The chain endpoints should be retrievable
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 0}, Amount: 1},
+			[]common.Hash{pm.chainman.GetBlockByNumber(0).Hash()},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.chainman.CurrentBlock().NumberU64()}, Amount: 1},
+			[]common.Hash{pm.chainman.CurrentBlock().Hash()},
+		},
+		// Ensure protocol limits are honored
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.chainman.CurrentBlock().NumberU64() - 1}, Amount: limit + 10, Reverse: true},
+			pm.chainman.GetBlockHashesFromHash(pm.chainman.CurrentBlock().Hash(), limit),
+		},
+		// Check that requesting more than available is handled gracefully
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.chainman.CurrentBlock().NumberU64() - 4}, Skip: 3, Amount: 3},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(pm.chainman.CurrentBlock().NumberU64() - 4).Hash(),
+				pm.chainman.GetBlockByNumber(pm.chainman.CurrentBlock().NumberU64()).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 4}, Skip: 3, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(4).Hash(),
+				pm.chainman.GetBlockByNumber(0).Hash(),
+			},
+		},
+		// Check that requesting more than available is handled gracefully, even if mid skip
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.chainman.CurrentBlock().NumberU64() - 4}, Skip: 2, Amount: 3},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(pm.chainman.CurrentBlock().NumberU64() - 4).Hash(),
+				pm.chainman.GetBlockByNumber(pm.chainman.CurrentBlock().NumberU64() - 1).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 4}, Skip: 2, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.chainman.GetBlockByNumber(4).Hash(),
+				pm.chainman.GetBlockByNumber(1).Hash(),
+			},
+		},
+		// Check that non existing headers aren't returned
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: unknown}, Amount: 1},
+			[]common.Hash{},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.chainman.CurrentBlock().NumberU64() + 1}, Amount: 1},
+			[]common.Hash{},
+		},
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Collect the headers to expect in the response
+		headers := []*types.Header{}
+		for _, hash := range tt.expect {
+			headers = append(headers, pm.chainman.GetBlock(hash).Header())
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x03, tt.query)
+		if err := p2p.ExpectMsg(peer.app, 0x04, headers); err != nil {
+			t.Errorf("test %d: headers mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that block contents can be retrieved from a remote chain based on their hashes.
+func TestGetBlockBodies62(t *testing.T) { testGetBlockBodies(t, 62) }
+func TestGetBlockBodies63(t *testing.T) { testGetBlockBodies(t, 63) }
+func TestGetBlockBodies64(t *testing.T) { testGetBlockBodies(t, 64) }
+
+func testGetBlockBodies(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(downloader.MaxBlockFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a batch of tests for various scenarios
+	limit := downloader.MaxBlockFetch
+	tests := []struct {
+		random    int           // Number of blocks to fetch randomly from the chain
+		explicit  []common.Hash // Explicitly requested blocks
+		available []bool        // Availability of explicitly requested blocks
+		expected  int           // Total number of existing blocks to expect
+	}{
+		{1, nil, nil, 1},                                                       // A single random block should be retrievable
+		{10, nil, nil, 10},                                                     // Multiple random blocks should be retrievable
+		{limit, nil, nil, limit},                                               // The maximum possible blocks should be retrievable
+		{limit + 1, nil, nil, limit},                                           // No more that the possible block count should be returned
+		{0, []common.Hash{pm.chainman.Genesis().Hash()}, []bool{true}, 1},      // The genesis block should be retrievable
+		{0, []common.Hash{pm.chainman.CurrentBlock().Hash()}, []bool{true}, 1}, // The chains head block should be retrievable
+		{0, []common.Hash{common.Hash{}}, []bool{false}, 0},                    // A non existent block should not be returned
+
+		// Existing and non-existing blocks interleaved should not cause problems
+		{0, []common.Hash{
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(1).Hash(),
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(10).Hash(),
+			common.Hash{},
+			pm.chainman.GetBlockByNumber(100).Hash(),
+			common.Hash{},
+		}, []bool{false, true, false, true, false, true, false}, 3},
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Collect the hashes to request, and the response to expect
+		hashes, seen := []common.Hash{}, make(map[int64]bool)
+		bodies := []*blockBody{}
+
+		for j := 0; j < tt.random; j++ {
+			for {
+				num := rand.Int63n(int64(pm.chainman.CurrentBlock().NumberU64()))
+				if !seen[num] {
+					seen[num] = true
+
+					block := pm.chainman.GetBlockByNumber(uint64(num))
+					hashes = append(hashes, block.Hash())
+					if len(bodies) < tt.expected {
+						bodies = append(bodies, &blockBody{Transactions: block.Transactions(), Uncles: block.Uncles()})
+					}
+					break
+				}
+			}
+		}
+		for j, hash := range tt.explicit {
+			hashes = append(hashes, hash)
+			if tt.available[j] && len(bodies) < tt.expected {
+				block := pm.chainman.GetBlock(hash)
+				bodies = append(bodies, &blockBody{Transactions: block.Transactions(), Uncles: block.Uncles()})
+			}
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x05, hashes)
+		if err := p2p.ExpectMsg(peer.app, 0x06, bodies); err != nil {
+			t.Errorf("test %d: bodies mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that the node state database can be retrieved based on hashes.
+func TestGetNodeData63(t *testing.T) { testGetNodeData(t, 63) }
+func TestGetNodeData64(t *testing.T) { testGetNodeData(t, 64) }
+
+func testGetNodeData(t *testing.T, protocol int) {
+	// Define three accounts to simulate transactions with
+	acc1Key, _ := crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
+	acc2Key, _ := crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
+	acc1Addr := crypto.PubkeyToAddress(acc1Key.PublicKey)
+	acc2Addr := crypto.PubkeyToAddress(acc2Key.PublicKey)
+
+	// Create a chain generator with some simple transactions (blatantly stolen from @fjl/chain_makerts_test)
+	generator := func(i int, block *core.BlockGen) {
+		switch i {
+		case 0:
+			// In block 1, the test bank sends account #1 some ether.
+			tx, _ := types.NewTransaction(block.TxNonce(testBankAddress), acc1Addr, big.NewInt(10000), params.TxGas, nil, nil).SignECDSA(testBankKey)
+			block.AddTx(tx)
+		case 1:
+			// In block 2, the test bank sends some more ether to account #1.
+			// acc1Addr passes it on to account #2.
+			tx1, _ := types.NewTransaction(block.TxNonce(testBankAddress), acc1Addr, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(testBankKey)
+			tx2, _ := types.NewTransaction(block.TxNonce(acc1Addr), acc2Addr, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(acc1Key)
+			block.AddTx(tx1)
+			block.AddTx(tx2)
+		case 2:
+			// Block 3 is empty but was mined by account #2.
+			block.SetCoinbase(acc2Addr)
+			block.SetExtra([]byte("yeehaw"))
+		case 3:
+			// Block 4 includes blocks 2 and 3 as uncle headers (with modified extra data).
+			b2 := block.PrevBlock(1).Header()
+			b2.Extra = []byte("foo")
+			block.AddUncle(b2)
+			b3 := block.PrevBlock(2).Header()
+			b3.Extra = []byte("foo")
+			block.AddUncle(b3)
+		}
+	}
+	// Assemble the test environment
+	pm := newTestProtocolManager(4, generator, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Fetch for now the entire chain db
+	hashes := []common.Hash{}
+	for _, key := range pm.chaindb.(*ethdb.MemDatabase).Keys() {
+		hashes = append(hashes, common.BytesToHash(key))
+	}
+	p2p.Send(peer.app, 0x0d, hashes)
+	msg, err := peer.app.ReadMsg()
+	if err != nil {
+		t.Fatalf("failed to read node data response: %v", err)
+	}
+	if msg.Code != 0x0e {
+		t.Fatalf("response packet code mismatch: have %x, want %x", msg.Code, 0x0c)
+	}
+	var data [][]byte
+	if err := msg.Decode(&data); err != nil {
+		t.Fatalf("failed to decode response node data: %v", err)
+	}
+	// Verify that all hashes correspond to the requested data, and reconstruct a state tree
+	for i, want := range hashes {
+		if hash := crypto.Sha3Hash(data[i]); hash != want {
+			fmt.Errorf("data hash mismatch: have %x, want %x", hash, want)
+		}
+	}
+	statedb, _ := ethdb.NewMemDatabase()
+	for i := 0; i < len(data); i++ {
+		statedb.Put(hashes[i].Bytes(), data[i])
+	}
+	accounts := []common.Address{testBankAddress, acc1Addr, acc2Addr}
+	for i := uint64(0); i <= pm.chainman.CurrentBlock().NumberU64(); i++ {
+		trie := state.New(pm.chainman.GetBlockByNumber(i).Root(), statedb)
+
+		for j, acc := range accounts {
+			bw := pm.chainman.State().GetBalance(acc)
+			bh := trie.GetBalance(acc)
+
+			if (bw != nil && bh == nil) || (bw == nil && bh != nil) {
+				t.Errorf("test %d, account %d: balance mismatch: have %v, want %v", i, j, bh, bw)
+			}
+			if bw != nil && bh != nil && bw.Cmp(bw) != 0 {
+				t.Errorf("test %d, account %d: balance mismatch: have %v, want %v", i, j, bh, bw)
+			}
+		}
+	}
+}
+
+// Tests that the transaction receipts can be retrieved based on hashes.
+func TestGetReceipt63(t *testing.T) { testGetReceipt(t, 63) }
+func TestGetReceipt64(t *testing.T) { testGetReceipt(t, 64) }
+
+func testGetReceipt(t *testing.T, protocol int) {
+	// Define three accounts to simulate transactions with
+	acc1Key, _ := crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
+	acc2Key, _ := crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
+	acc1Addr := crypto.PubkeyToAddress(acc1Key.PublicKey)
+	acc2Addr := crypto.PubkeyToAddress(acc2Key.PublicKey)
+
+	// Create a chain generator with some simple transactions (blatantly stolen from @fjl/chain_makerts_test)
+	generator := func(i int, block *core.BlockGen) {
+		switch i {
+		case 0:
+			// In block 1, the test bank sends account #1 some ether.
+			tx, _ := types.NewTransaction(block.TxNonce(testBankAddress), acc1Addr, big.NewInt(10000), params.TxGas, nil, nil).SignECDSA(testBankKey)
+			block.AddTx(tx)
+		case 1:
+			// In block 2, the test bank sends some more ether to account #1.
+			// acc1Addr passes it on to account #2.
+			tx1, _ := types.NewTransaction(block.TxNonce(testBankAddress), acc1Addr, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(testBankKey)
+			tx2, _ := types.NewTransaction(block.TxNonce(acc1Addr), acc2Addr, big.NewInt(1000), params.TxGas, nil, nil).SignECDSA(acc1Key)
+			block.AddTx(tx1)
+			block.AddTx(tx2)
+		case 2:
+			// Block 3 is empty but was mined by account #2.
+			block.SetCoinbase(acc2Addr)
+			block.SetExtra([]byte("yeehaw"))
+		case 3:
+			// Block 4 includes blocks 2 and 3 as uncle headers (with modified extra data).
+			b2 := block.PrevBlock(1).Header()
+			b2.Extra = []byte("foo")
+			block.AddUncle(b2)
+			b3 := block.PrevBlock(2).Header()
+			b3.Extra = []byte("foo")
+			block.AddUncle(b3)
+		}
+	}
+	// Assemble the test environment
+	pm := newTestProtocolManager(4, generator, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Collect the hashes to request, and the response to expect
+	hashes := []common.Hash{}
+	for i := uint64(0); i <= pm.chainman.CurrentBlock().NumberU64(); i++ {
+		for _, tx := range pm.chainman.GetBlockByNumber(i).Transactions() {
+			hashes = append(hashes, tx.Hash())
+		}
+	}
+	receipts := make([]*types.Receipt, len(hashes))
+	for i, hash := range hashes {
+		receipts[i] = core.GetReceipt(pm.chaindb, hash)
+	}
+	// Send the hash request and verify the response
+	p2p.Send(peer.app, 0x0f, hashes)
+	if err := p2p.ExpectMsg(peer.app, 0x10, receipts); err != nil {
+		t.Errorf("receipts mismatch: %v", err)
+	}
+}
diff --git a/eth/helper_test.go b/eth/helper_test.go
new file mode 100644
index 000000000..3a799e6f6
--- /dev/null
+++ b/eth/helper_test.go
@@ -0,0 +1,147 @@
+// This file contains some shares testing functionality, common to  multiple
+// different files and modules being tested.
+
+package eth
+
+import (
+	"crypto/rand"
+	"math/big"
+	"sync"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/p2p"
+	"github.com/ethereum/go-ethereum/p2p/discover"
+)
+
+var (
+	testBankKey, _  = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+	testBankAddress = crypto.PubkeyToAddress(testBankKey.PublicKey)
+	testBankFunds   = big.NewInt(1000000)
+)
+
+// newTestProtocolManager creates a new protocol manager for testing purposes,
+// with the given number of blocks already known, and potential notification
+// channels for different events.
+func newTestProtocolManager(blocks int, generator func(int, *core.BlockGen), newtx chan<- []*types.Transaction) *ProtocolManager {
+	var (
+		evmux       = new(event.TypeMux)
+		pow         = new(core.FakePow)
+		db, _       = ethdb.NewMemDatabase()
+		genesis     = core.WriteGenesisBlockForTesting(db, testBankAddress, testBankFunds)
+		chainman, _ = core.NewChainManager(db, pow, evmux)
+		blockproc   = core.NewBlockProcessor(db, pow, chainman, evmux)
+	)
+	chainman.SetProcessor(blockproc)
+	if _, err := chainman.InsertChain(core.GenerateChain(genesis, db, blocks, generator)); err != nil {
+		panic(err)
+	}
+	pm := NewProtocolManager(NetworkId, evmux, &testTxPool{added: newtx}, pow, chainman, db)
+	pm.Start()
+	return pm
+}
+
+// testTxPool is a fake, helper transaction pool for testing purposes
+type testTxPool struct {
+	pool  []*types.Transaction        // Collection of all transactions
+	added chan<- []*types.Transaction // Notification channel for new transactions
+
+	lock sync.RWMutex // Protects the transaction pool
+}
+
+// AddTransactions appends a batch of transactions to the pool, and notifies any
+// listeners if the addition channel is non nil
+func (p *testTxPool) AddTransactions(txs []*types.Transaction) {
+	p.lock.Lock()
+	defer p.lock.Unlock()
+
+	p.pool = append(p.pool, txs...)
+	if p.added != nil {
+		p.added <- txs
+	}
+}
+
+// GetTransactions returns all the transactions known to the pool
+func (p *testTxPool) GetTransactions() types.Transactions {
+	p.lock.RLock()
+	defer p.lock.RUnlock()
+
+	txs := make([]*types.Transaction, len(p.pool))
+	copy(txs, p.pool)
+
+	return txs
+}
+
+// newTestTransaction create a new dummy transaction.
+func newTestTransaction(from *crypto.Key, nonce uint64, datasize int) *types.Transaction {
+	tx := types.NewTransaction(nonce, common.Address{}, big.NewInt(0), big.NewInt(100000), big.NewInt(0), make([]byte, datasize))
+	tx, _ = tx.SignECDSA(from.PrivateKey)
+
+	return tx
+}
+
+// testPeer is a simulated peer to allow testing direct network calls.
+type testPeer struct {
+	net p2p.MsgReadWriter // Network layer reader/writer to simulate remote messaging
+	app *p2p.MsgPipeRW    // Application layer reader/writer to simulate the local side
+	*peer
+}
+
+// newTestPeer creates a new peer registered at the given protocol manager.
+func newTestPeer(name string, version int, pm *ProtocolManager, shake bool) (*testPeer, <-chan error) {
+	// Create a message pipe to communicate through
+	app, net := p2p.MsgPipe()
+
+	// Generate a random id and create the peer
+	var id discover.NodeID
+	rand.Read(id[:])
+
+	peer := pm.newPeer(version, NetworkId, p2p.NewPeer(id, name, nil), net)
+
+	// Start the peer on a new thread
+	errc := make(chan error, 1)
+	go func() {
+		pm.newPeerCh <- peer
+		errc <- pm.handle(peer)
+	}()
+	tp := &testPeer{
+		app:  app,
+		net:  net,
+		peer: peer,
+	}
+	// Execute any implicitly requested handshakes and return
+	if shake {
+		td, head, genesis := pm.chainman.Status()
+		tp.handshake(nil, td, head, genesis)
+	}
+	return tp, errc
+}
+
+// handshake simulates a trivial handshake that expects the same state from the
+// remote side as we are simulating locally.
+func (p *testPeer) handshake(t *testing.T, td *big.Int, head common.Hash, genesis common.Hash) {
+	msg := &statusData{
+		ProtocolVersion: uint32(p.version),
+		NetworkId:       uint32(NetworkId),
+		TD:              td,
+		CurrentBlock:    head,
+		GenesisBlock:    genesis,
+	}
+	if err := p2p.ExpectMsg(p.app, StatusMsg, msg); err != nil {
+		t.Fatalf("status recv: %v", err)
+	}
+	if err := p2p.Send(p.app, StatusMsg, msg); err != nil {
+		t.Fatalf("status send: %v", err)
+	}
+}
+
+// close terminates the local side of the peer, notifying the remote protocol
+// manager of termination.
+func (p *testPeer) close() {
+	p.app.Close()
+}
diff --git a/eth/metrics.go b/eth/metrics.go
index 625b90b67..cfab3bcb3 100644
--- a/eth/metrics.go
+++ b/eth/metrics.go
@@ -18,27 +18,140 @@ package eth
 
 import (
 	"github.com/ethereum/go-ethereum/metrics"
+	"github.com/ethereum/go-ethereum/p2p"
 )
 
 var (
-	propTxnInPacketsMeter    = metrics.NewMeter("eth/prop/txns/in/packets")
-	propTxnInTrafficMeter    = metrics.NewMeter("eth/prop/txns/in/traffic")
-	propTxnOutPacketsMeter   = metrics.NewMeter("eth/prop/txns/out/packets")
-	propTxnOutTrafficMeter   = metrics.NewMeter("eth/prop/txns/out/traffic")
-	propHashInPacketsMeter   = metrics.NewMeter("eth/prop/hashes/in/packets")
-	propHashInTrafficMeter   = metrics.NewMeter("eth/prop/hashes/in/traffic")
-	propHashOutPacketsMeter  = metrics.NewMeter("eth/prop/hashes/out/packets")
-	propHashOutTrafficMeter  = metrics.NewMeter("eth/prop/hashes/out/traffic")
-	propBlockInPacketsMeter  = metrics.NewMeter("eth/prop/blocks/in/packets")
-	propBlockInTrafficMeter  = metrics.NewMeter("eth/prop/blocks/in/traffic")
-	propBlockOutPacketsMeter = metrics.NewMeter("eth/prop/blocks/out/packets")
-	propBlockOutTrafficMeter = metrics.NewMeter("eth/prop/blocks/out/traffic")
-	reqHashInPacketsMeter    = metrics.NewMeter("eth/req/hashes/in/packets")
-	reqHashInTrafficMeter    = metrics.NewMeter("eth/req/hashes/in/traffic")
-	reqHashOutPacketsMeter   = metrics.NewMeter("eth/req/hashes/out/packets")
-	reqHashOutTrafficMeter   = metrics.NewMeter("eth/req/hashes/out/traffic")
-	reqBlockInPacketsMeter   = metrics.NewMeter("eth/req/blocks/in/packets")
-	reqBlockInTrafficMeter   = metrics.NewMeter("eth/req/blocks/in/traffic")
-	reqBlockOutPacketsMeter  = metrics.NewMeter("eth/req/blocks/out/packets")
-	reqBlockOutTrafficMeter  = metrics.NewMeter("eth/req/blocks/out/traffic")
+	propTxnInPacketsMeter     = metrics.NewMeter("eth/prop/txns/in/packets")
+	propTxnInTrafficMeter     = metrics.NewMeter("eth/prop/txns/in/traffic")
+	propTxnOutPacketsMeter    = metrics.NewMeter("eth/prop/txns/out/packets")
+	propTxnOutTrafficMeter    = metrics.NewMeter("eth/prop/txns/out/traffic")
+	propHashInPacketsMeter    = metrics.NewMeter("eth/prop/hashes/in/packets")
+	propHashInTrafficMeter    = metrics.NewMeter("eth/prop/hashes/in/traffic")
+	propHashOutPacketsMeter   = metrics.NewMeter("eth/prop/hashes/out/packets")
+	propHashOutTrafficMeter   = metrics.NewMeter("eth/prop/hashes/out/traffic")
+	propBlockInPacketsMeter   = metrics.NewMeter("eth/prop/blocks/in/packets")
+	propBlockInTrafficMeter   = metrics.NewMeter("eth/prop/blocks/in/traffic")
+	propBlockOutPacketsMeter  = metrics.NewMeter("eth/prop/blocks/out/packets")
+	propBlockOutTrafficMeter  = metrics.NewMeter("eth/prop/blocks/out/traffic")
+	reqHashInPacketsMeter     = metrics.NewMeter("eth/req/hashes/in/packets")
+	reqHashInTrafficMeter     = metrics.NewMeter("eth/req/hashes/in/traffic")
+	reqHashOutPacketsMeter    = metrics.NewMeter("eth/req/hashes/out/packets")
+	reqHashOutTrafficMeter    = metrics.NewMeter("eth/req/hashes/out/traffic")
+	reqBlockInPacketsMeter    = metrics.NewMeter("eth/req/blocks/in/packets")
+	reqBlockInTrafficMeter    = metrics.NewMeter("eth/req/blocks/in/traffic")
+	reqBlockOutPacketsMeter   = metrics.NewMeter("eth/req/blocks/out/packets")
+	reqBlockOutTrafficMeter   = metrics.NewMeter("eth/req/blocks/out/traffic")
+	reqHeaderInPacketsMeter   = metrics.NewMeter("eth/req/headers/in/packets")
+	reqHeaderInTrafficMeter   = metrics.NewMeter("eth/req/headers/in/traffic")
+	reqHeaderOutPacketsMeter  = metrics.NewMeter("eth/req/headers/out/packets")
+	reqHeaderOutTrafficMeter  = metrics.NewMeter("eth/req/headers/out/traffic")
+	reqBodyInPacketsMeter     = metrics.NewMeter("eth/req/bodies/in/packets")
+	reqBodyInTrafficMeter     = metrics.NewMeter("eth/req/bodies/in/traffic")
+	reqBodyOutPacketsMeter    = metrics.NewMeter("eth/req/bodies/out/packets")
+	reqBodyOutTrafficMeter    = metrics.NewMeter("eth/req/bodies/out/traffic")
+	reqStateInPacketsMeter    = metrics.NewMeter("eth/req/states/in/packets")
+	reqStateInTrafficMeter    = metrics.NewMeter("eth/req/states/in/traffic")
+	reqStateOutPacketsMeter   = metrics.NewMeter("eth/req/states/out/packets")
+	reqStateOutTrafficMeter   = metrics.NewMeter("eth/req/states/out/traffic")
+	reqReceiptInPacketsMeter  = metrics.NewMeter("eth/req/receipts/in/packets")
+	reqReceiptInTrafficMeter  = metrics.NewMeter("eth/req/receipts/in/traffic")
+	reqReceiptOutPacketsMeter = metrics.NewMeter("eth/req/receipts/out/packets")
+	reqReceiptOutTrafficMeter = metrics.NewMeter("eth/req/receipts/out/traffic")
+	miscInPacketsMeter        = metrics.NewMeter("eth/misc/in/packets")
+	miscInTrafficMeter        = metrics.NewMeter("eth/misc/in/traffic")
+	miscOutPacketsMeter       = metrics.NewMeter("eth/misc/out/packets")
+	miscOutTrafficMeter       = metrics.NewMeter("eth/misc/out/traffic")
 )
+
+// meteredMsgReadWriter is a wrapper around a p2p.MsgReadWriter, capable of
+// accumulating the above defined metrics based on the data stream contents.
+type meteredMsgReadWriter struct {
+	p2p.MsgReadWriter     // Wrapped message stream to meter
+	version           int // Protocol version to select correct meters
+}
+
+// newMeteredMsgWriter wraps a p2p MsgReadWriter with metering support. If the
+// metrics system is disabled, this fucntion returns the original object.
+func newMeteredMsgWriter(rw p2p.MsgReadWriter) p2p.MsgReadWriter {
+	if !metrics.Enabled {
+		return rw
+	}
+	return &meteredMsgReadWriter{MsgReadWriter: rw}
+}
+
+// Init sets the protocol version used by the stream to know which meters to
+// increment in case of overlapping message ids between protocol versions.
+func (rw *meteredMsgReadWriter) Init(version int) {
+	rw.version = version
+}
+
+func (rw *meteredMsgReadWriter) ReadMsg() (p2p.Msg, error) {
+	// Read the message and short circuit in case of an error
+	msg, err := rw.MsgReadWriter.ReadMsg()
+	if err != nil {
+		return msg, err
+	}
+	// Account for the data traffic
+	packets, traffic := miscInPacketsMeter, miscInTrafficMeter
+	switch {
+	case rw.version < eth62 && msg.Code == BlockHashesMsg:
+		packets, traffic = reqHashInPacketsMeter, reqHashInTrafficMeter
+	case rw.version < eth62 && msg.Code == BlocksMsg:
+		packets, traffic = reqBlockInPacketsMeter, reqBlockInTrafficMeter
+
+	case rw.version >= eth62 && msg.Code == BlockHeadersMsg:
+		packets, traffic = reqBlockInPacketsMeter, reqBlockInTrafficMeter
+	case rw.version >= eth62 && msg.Code == BlockBodiesMsg:
+		packets, traffic = reqBodyInPacketsMeter, reqBodyInTrafficMeter
+
+	case rw.version >= eth63 && msg.Code == NodeDataMsg:
+		packets, traffic = reqStateInPacketsMeter, reqStateInTrafficMeter
+	case rw.version >= eth63 && msg.Code == ReceiptsMsg:
+		packets, traffic = reqReceiptInPacketsMeter, reqReceiptInTrafficMeter
+
+	case msg.Code == NewBlockHashesMsg:
+		packets, traffic = propHashInPacketsMeter, propHashInTrafficMeter
+	case msg.Code == NewBlockMsg:
+		packets, traffic = propBlockInPacketsMeter, propBlockInTrafficMeter
+	case msg.Code == TxMsg:
+		packets, traffic = propTxnInPacketsMeter, propTxnInTrafficMeter
+	}
+	packets.Mark(1)
+	traffic.Mark(int64(msg.Size))
+
+	return msg, err
+}
+
+func (rw *meteredMsgReadWriter) WriteMsg(msg p2p.Msg) error {
+	// Account for the data traffic
+	packets, traffic := miscOutPacketsMeter, miscOutTrafficMeter
+	switch {
+	case rw.version < eth62 && msg.Code == BlockHashesMsg:
+		packets, traffic = reqHashOutPacketsMeter, reqHashOutTrafficMeter
+	case rw.version < eth62 && msg.Code == BlocksMsg:
+		packets, traffic = reqBlockOutPacketsMeter, reqBlockOutTrafficMeter
+
+	case rw.version >= eth62 && msg.Code == BlockHeadersMsg:
+		packets, traffic = reqHeaderOutPacketsMeter, reqHeaderOutTrafficMeter
+	case rw.version >= eth62 && msg.Code == BlockBodiesMsg:
+		packets, traffic = reqBodyOutPacketsMeter, reqBodyOutTrafficMeter
+
+	case rw.version >= eth63 && msg.Code == NodeDataMsg:
+		packets, traffic = reqStateOutPacketsMeter, reqStateOutTrafficMeter
+	case rw.version >= eth63 && msg.Code == ReceiptsMsg:
+		packets, traffic = reqReceiptOutPacketsMeter, reqReceiptOutTrafficMeter
+
+	case msg.Code == NewBlockHashesMsg:
+		packets, traffic = propHashOutPacketsMeter, propHashOutTrafficMeter
+	case msg.Code == NewBlockMsg:
+		packets, traffic = propBlockOutPacketsMeter, propBlockOutTrafficMeter
+	case msg.Code == TxMsg:
+		packets, traffic = propTxnOutPacketsMeter, propTxnOutTrafficMeter
+	}
+	packets.Mark(1)
+	traffic.Mark(int64(msg.Size))
+
+	// Send the packet to the p2p layer
+	return rw.MsgReadWriter.WriteMsg(msg)
+}
diff --git a/eth/peer.go b/eth/peer.go
index ade1f37ea..8d7c48885 100644
--- a/eth/peer.go
+++ b/eth/peer.go
@@ -129,9 +129,7 @@ func (p *peer) MarkTransaction(hash common.Hash) {
 // SendTransactions sends transactions to the peer and includes the hashes
 // in its transaction hash set for future reference.
 func (p *peer) SendTransactions(txs types.Transactions) error {
-	propTxnOutPacketsMeter.Mark(1)
 	for _, tx := range txs {
-		propTxnOutTrafficMeter.Mark(tx.Size().Int64())
 		p.knownTxs.Add(tx.Hash())
 	}
 	return p2p.Send(p.rw, TxMsg, txs)
@@ -139,62 +137,126 @@ func (p *peer) SendTransactions(txs types.Transactions) error {
 
 // SendBlockHashes sends a batch of known hashes to the remote peer.
 func (p *peer) SendBlockHashes(hashes []common.Hash) error {
-	reqHashOutPacketsMeter.Mark(1)
-	reqHashOutTrafficMeter.Mark(int64(32 * len(hashes)))
-
 	return p2p.Send(p.rw, BlockHashesMsg, hashes)
 }
 
 // SendBlocks sends a batch of blocks to the remote peer.
 func (p *peer) SendBlocks(blocks []*types.Block) error {
-	reqBlockOutPacketsMeter.Mark(1)
-	for _, block := range blocks {
-		reqBlockOutTrafficMeter.Mark(block.Size().Int64())
-	}
 	return p2p.Send(p.rw, BlocksMsg, blocks)
 }
 
-// SendNewBlockHashes announces the availability of a number of blocks through
+// SendNewBlockHashes61 announces the availability of a number of blocks through
 // a hash notification.
-func (p *peer) SendNewBlockHashes(hashes []common.Hash) error {
-	propHashOutPacketsMeter.Mark(1)
-	propHashOutTrafficMeter.Mark(int64(32 * len(hashes)))
-
+func (p *peer) SendNewBlockHashes61(hashes []common.Hash) error {
 	for _, hash := range hashes {
 		p.knownBlocks.Add(hash)
 	}
 	return p2p.Send(p.rw, NewBlockHashesMsg, hashes)
 }
 
+// SendNewBlockHashes announces the availability of a number of blocks through
+// a hash notification.
+func (p *peer) SendNewBlockHashes(hashes []common.Hash, numbers []uint64) error {
+	for _, hash := range hashes {
+		p.knownBlocks.Add(hash)
+	}
+	request := make(newBlockHashesData, len(hashes))
+	for i := 0; i < len(hashes); i++ {
+		request[i].Hash = hashes[i]
+		request[i].Number = numbers[i]
+	}
+	return p2p.Send(p.rw, NewBlockHashesMsg, request)
+}
+
 // SendNewBlock propagates an entire block to a remote peer.
 func (p *peer) SendNewBlock(block *types.Block, td *big.Int) error {
-	propBlockOutPacketsMeter.Mark(1)
-	propBlockOutTrafficMeter.Mark(block.Size().Int64())
-
 	p.knownBlocks.Add(block.Hash())
 	return p2p.Send(p.rw, NewBlockMsg, []interface{}{block, td})
 }
 
+// SendBlockHeaders sends a batch of block headers to the remote peer.
+func (p *peer) SendBlockHeaders(headers []*types.Header) error {
+	return p2p.Send(p.rw, BlockHeadersMsg, headers)
+}
+
+// SendBlockBodies sends a batch of block contents to the remote peer.
+func (p *peer) SendBlockBodies(bodies []*blockBody) error {
+	return p2p.Send(p.rw, BlockBodiesMsg, blockBodiesData(bodies))
+}
+
+// SendNodeData sends a batch of arbitrary internal data, corresponding to the
+// hashes requested.
+func (p *peer) SendNodeData(data [][]byte) error {
+	return p2p.Send(p.rw, NodeDataMsg, data)
+}
+
+// SendReceipts sends a batch of transaction receipts, corresponding to the ones
+// requested.
+func (p *peer) SendReceipts(receipts []*types.Receipt) error {
+	return p2p.Send(p.rw, ReceiptsMsg, receipts)
+}
+
 // RequestHashes fetches a batch of hashes from a peer, starting at from, going
 // towards the genesis block.
 func (p *peer) RequestHashes(from common.Hash) error {
-	glog.V(logger.Debug).Infof("Peer [%s] fetching hashes (%d) from %x...\n", p.id, downloader.MaxHashFetch, from[:4])
+	glog.V(logger.Debug).Infof("%v fetching hashes (%d) from %x...", p, downloader.MaxHashFetch, from[:4])
 	return p2p.Send(p.rw, GetBlockHashesMsg, getBlockHashesData{from, uint64(downloader.MaxHashFetch)})
 }
 
-// RequestHashesFromNumber fetches a batch of hashes from a peer, starting at the
-// requested block number, going upwards towards the genesis block.
+// RequestHashesFromNumber fetches a batch of hashes from a peer, starting at
+// the requested block number, going upwards towards the genesis block.
 func (p *peer) RequestHashesFromNumber(from uint64, count int) error {
-	glog.V(logger.Debug).Infof("Peer [%s] fetching hashes (%d) from #%d...\n", p.id, count, from)
+	glog.V(logger.Debug).Infof("%v fetching hashes (%d) from #%d...", p, count, from)
 	return p2p.Send(p.rw, GetBlockHashesFromNumberMsg, getBlockHashesFromNumberData{from, uint64(count)})
 }
 
 // RequestBlocks fetches a batch of blocks corresponding to the specified hashes.
 func (p *peer) RequestBlocks(hashes []common.Hash) error {
-	glog.V(logger.Debug).Infof("[%s] fetching %v blocks\n", p.id, len(hashes))
+	glog.V(logger.Debug).Infof("%v fetching %v blocks", p, len(hashes))
 	return p2p.Send(p.rw, GetBlocksMsg, hashes)
 }
 
+// RequestHeaders is a wrapper around the header query functions to fetch a
+// single header. It is used solely by the fetcher.
+func (p *peer) RequestOneHeader(hash common.Hash) error {
+	glog.V(logger.Debug).Infof("%v fetching a single header: %x", p, hash)
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &getBlockHeadersData{Origin: hashOrNumber{Hash: hash}, Amount: uint64(1), Skip: uint64(0), Reverse: false})
+}
+
+// RequestHeadersByHash fetches a batch of blocks' headers corresponding to the
+// specified header query, based on the hash of an origin block.
+func (p *peer) RequestHeadersByHash(origin common.Hash, amount int, skip int, reverse bool) error {
+	glog.V(logger.Debug).Infof("%v fetching %d headers from %x, skipping %d (reverse = %v)", p, amount, origin[:4], skip, reverse)
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &getBlockHeadersData{Origin: hashOrNumber{Hash: origin}, Amount: uint64(amount), Skip: uint64(skip), Reverse: reverse})
+}
+
+// RequestHeadersByNumber fetches a batch of blocks' headers corresponding to the
+// specified header query, based on the number of an origin block.
+func (p *peer) RequestHeadersByNumber(origin uint64, amount int, skip int, reverse bool) error {
+	glog.V(logger.Debug).Infof("%v fetching %d headers from #%d, skipping %d (reverse = %v)", p, amount, origin, skip, reverse)
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &getBlockHeadersData{Origin: hashOrNumber{Number: origin}, Amount: uint64(amount), Skip: uint64(skip), Reverse: reverse})
+}
+
+// RequestBodies fetches a batch of blocks' bodies corresponding to the hashes
+// specified.
+func (p *peer) RequestBodies(hashes []common.Hash) error {
+	glog.V(logger.Debug).Infof("%v fetching %d block bodies", p, len(hashes))
+	return p2p.Send(p.rw, GetBlockBodiesMsg, hashes)
+}
+
+// RequestNodeData fetches a batch of arbitrary data from a node's known state
+// data, corresponding to the specified hashes.
+func (p *peer) RequestNodeData(hashes []common.Hash) error {
+	glog.V(logger.Debug).Infof("%v fetching %v state data", p, len(hashes))
+	return p2p.Send(p.rw, GetNodeDataMsg, hashes)
+}
+
+// RequestReceipts fetches a batch of transaction receipts from a remote node.
+func (p *peer) RequestReceipts(hashes []common.Hash) error {
+	glog.V(logger.Debug).Infof("%v fetching %v receipts", p, len(hashes))
+	return p2p.Send(p.rw, GetReceiptsMsg, hashes)
+}
+
 // Handshake executes the eth protocol handshake, negotiating version number,
 // network IDs, difficulties, head and genesis blocks.
 func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) error {
diff --git a/eth/protocol.go b/eth/protocol.go
index b8c9b50d0..49f096a3b 100644
--- a/eth/protocol.go
+++ b/eth/protocol.go
@@ -17,17 +17,28 @@
 package eth
 
 import (
+	"fmt"
+	"io"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rlp"
+)
+
+// Constants to match up protocol versions and messages
+const (
+	eth61 = 61
+	eth62 = 62
+	eth63 = 63
+	eth64 = 64
 )
 
 // Supported versions of the eth protocol (first is primary).
-var ProtocolVersions = []uint{61, 60}
+var ProtocolVersions = []uint{eth64, eth63, eth62, eth61}
 
 // Number of implemented message corresponding to different protocol versions.
-var ProtocolLengths = []uint64{9, 8}
+var ProtocolLengths = []uint64{15, 12, 8, 9}
 
 const (
 	NetworkId          = 1
@@ -36,15 +47,37 @@ const (
 
 // eth protocol message codes
 const (
-	StatusMsg = iota
-	NewBlockHashesMsg
-	TxMsg
-	GetBlockHashesMsg
-	BlockHashesMsg
-	GetBlocksMsg
-	BlocksMsg
-	NewBlockMsg
-	GetBlockHashesFromNumberMsg
+	// Protocol messages belonging to eth/61
+	StatusMsg                   = 0x00
+	NewBlockHashesMsg           = 0x01
+	TxMsg                       = 0x02
+	GetBlockHashesMsg           = 0x03
+	BlockHashesMsg              = 0x04
+	GetBlocksMsg                = 0x05
+	BlocksMsg                   = 0x06
+	NewBlockMsg                 = 0x07
+	GetBlockHashesFromNumberMsg = 0x08
+
+	// Protocol messages belonging to eth/62 (new protocol from scratch)
+	// StatusMsg          = 0x00 (uncomment after eth/61 deprecation)
+	// NewBlockHashesMsg  = 0x01 (uncomment after eth/61 deprecation)
+	// TxMsg              = 0x02 (uncomment after eth/61 deprecation)
+	GetBlockHeadersMsg = 0x03
+	BlockHeadersMsg    = 0x04
+	GetBlockBodiesMsg  = 0x05
+	BlockBodiesMsg     = 0x06
+	// 	NewBlockMsg       = 0x07 (uncomment after eth/61 deprecation)
+
+	// Protocol messages belonging to eth/63
+	GetNodeDataMsg = 0x0d
+	NodeDataMsg    = 0x0e
+	GetReceiptsMsg = 0x0f
+	ReceiptsMsg    = 0x10
+
+	// Protocol messages belonging to eth/64
+	GetAcctProofMsg     = 0x11
+	GetStorageDataProof = 0x12
+	Proof               = 0x13
 )
 
 type errCode int
@@ -102,22 +135,85 @@ type statusData struct {
 	GenesisBlock    common.Hash
 }
 
-// getBlockHashesData is the network packet for the hash based block retrieval
-// message.
+// newBlockHashesData is the network packet for the block announcements.
+type newBlockHashesData []struct {
+	Hash   common.Hash // Hash of one particular block being announced
+	Number uint64      // Number of one particular block being announced
+}
+
+// getBlockHashesData is the network packet for the hash based hash retrieval.
 type getBlockHashesData struct {
 	Hash   common.Hash
 	Amount uint64
 }
 
-// getBlockHashesFromNumberData is the network packet for the number based block
-// retrieval message.
+// getBlockHashesFromNumberData is the network packet for the number based hash
+// retrieval.
 type getBlockHashesFromNumberData struct {
 	Number uint64
 	Amount uint64
 }
 
+// getBlockHeadersData represents a block header query.
+type getBlockHeadersData struct {
+	Origin  hashOrNumber // Block from which to retrieve headers
+	Amount  uint64       // Maximum number of headers to retrieve
+	Skip    uint64       // Blocks to skip between consecutive headers
+	Reverse bool         // Query direction (false = rising towards latest, true = falling towards genesis)
+}
+
+// hashOrNumber is a combined field for specifying an origin block.
+type hashOrNumber struct {
+	Hash   common.Hash // Block hash from which to retrieve headers (excludes Number)
+	Number uint64      // Block hash from which to retrieve headers (excludes Hash)
+}
+
+// EncodeRLP is a specialized encoder for hashOrNumber to encode only one of the
+// two contained union fields.
+func (hn *hashOrNumber) EncodeRLP(w io.Writer) error {
+	if hn.Hash == (common.Hash{}) {
+		return rlp.Encode(w, hn.Number)
+	}
+	if hn.Number != 0 {
+		return fmt.Errorf("both origin hash (%x) and number (%d) provided", hn.Hash, hn.Number)
+	}
+	return rlp.Encode(w, hn.Hash)
+}
+
+// DecodeRLP is a specialized decoder for hashOrNumber to decode the contents
+// into either a block hash or a block number.
+func (hn *hashOrNumber) DecodeRLP(s *rlp.Stream) error {
+	_, size, _ := s.Kind()
+	origin, err := s.Raw()
+	if err == nil {
+		switch {
+		case size == 32:
+			err = rlp.DecodeBytes(origin, &hn.Hash)
+		case size <= 8:
+			err = rlp.DecodeBytes(origin, &hn.Number)
+		default:
+			err = fmt.Errorf("invalid input size %d for origin", size)
+		}
+	}
+	return err
+}
+
 // newBlockData is the network packet for the block propagation message.
 type newBlockData struct {
 	Block *types.Block
 	TD    *big.Int
 }
+
+// blockBody represents the data content of a single block.
+type blockBody struct {
+	Transactions []*types.Transaction // Transactions contained within a block
+	Uncles       []*types.Header      // Uncles contained within a block
+}
+
+// blockBodiesData is the network packet for block content distribution.
+type blockBodiesData []*blockBody
+
+// nodeDataData is the network response packet for a node data retrieval.
+type nodeDataData []struct {
+	Value []byte
+}
diff --git a/eth/protocol_test.go b/eth/protocol_test.go
index 08c9b6a06..bc3b5acfc 100644
--- a/eth/protocol_test.go
+++ b/eth/protocol_test.go
@@ -18,19 +18,16 @@ package eth
 
 import (
 	"crypto/rand"
-	"math/big"
+	"fmt"
 	"sync"
 	"testing"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/ethdb"
-	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/rlp"
 )
 
 func init() {
@@ -40,8 +37,14 @@ func init() {
 
 var testAccount = crypto.NewKey(rand.Reader)
 
-func TestStatusMsgErrors(t *testing.T) {
-	pm := newProtocolManagerForTesting(nil)
+// Tests that handshake failures are detected and reported correctly.
+func TestStatusMsgErrors61(t *testing.T) { testStatusMsgErrors(t, 61) }
+func TestStatusMsgErrors62(t *testing.T) { testStatusMsgErrors(t, 62) }
+func TestStatusMsgErrors63(t *testing.T) { testStatusMsgErrors(t, 63) }
+func TestStatusMsgErrors64(t *testing.T) { testStatusMsgErrors(t, 64) }
+
+func testStatusMsgErrors(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(0, nil, nil)
 	td, currentBlock, genesis := pm.chainman.Status()
 	defer pm.Stop()
 
@@ -56,23 +59,23 @@ func TestStatusMsgErrors(t *testing.T) {
 		},
 		{
 			code: StatusMsg, data: statusData{10, NetworkId, td, currentBlock, genesis},
-			wantError: errResp(ErrProtocolVersionMismatch, "10 (!= 0)"),
+			wantError: errResp(ErrProtocolVersionMismatch, "10 (!= %d)", protocol),
 		},
 		{
-			code: StatusMsg, data: statusData{uint32(ProtocolVersions[0]), 999, td, currentBlock, genesis},
+			code: StatusMsg, data: statusData{uint32(protocol), 999, td, currentBlock, genesis},
 			wantError: errResp(ErrNetworkIdMismatch, "999 (!= 1)"),
 		},
 		{
-			code: StatusMsg, data: statusData{uint32(ProtocolVersions[0]), NetworkId, td, currentBlock, common.Hash{3}},
+			code: StatusMsg, data: statusData{uint32(protocol), NetworkId, td, currentBlock, common.Hash{3}},
 			wantError: errResp(ErrGenesisBlockMismatch, "0300000000000000000000000000000000000000000000000000000000000000 (!= %x)", genesis),
 		},
 	}
 
 	for i, test := range tests {
-		p, errc := newTestPeer(pm)
+		p, errc := newTestPeer("peer", protocol, pm, false)
 		// The send call might hang until reset because
 		// the protocol might not read the payload.
-		go p2p.Send(p, test.code, test.data)
+		go p2p.Send(p.app, test.code, test.data)
 
 		select {
 		case err := <-errc:
@@ -89,16 +92,20 @@ func TestStatusMsgErrors(t *testing.T) {
 }
 
 // This test checks that received transactions are added to the local pool.
-func TestRecvTransactions(t *testing.T) {
+func TestRecvTransactions61(t *testing.T) { testRecvTransactions(t, 61) }
+func TestRecvTransactions62(t *testing.T) { testRecvTransactions(t, 62) }
+func TestRecvTransactions63(t *testing.T) { testRecvTransactions(t, 63) }
+func TestRecvTransactions64(t *testing.T) { testRecvTransactions(t, 64) }
+
+func testRecvTransactions(t *testing.T, protocol int) {
 	txAdded := make(chan []*types.Transaction)
-	pm := newProtocolManagerForTesting(txAdded)
-	p, _ := newTestPeer(pm)
+	pm := newTestProtocolManager(0, nil, txAdded)
+	p, _ := newTestPeer("peer", protocol, pm, true)
 	defer pm.Stop()
 	defer p.close()
-	p.handshake(t)
 
-	tx := newtx(testAccount, 0, 0)
-	if err := p2p.Send(p, TxMsg, []interface{}{tx}); err != nil {
+	tx := newTestTransaction(testAccount, 0, 0)
+	if err := p2p.Send(p.app, TxMsg, []interface{}{tx}); err != nil {
 		t.Fatalf("send error: %v", err)
 	}
 	select {
@@ -114,15 +121,20 @@ func TestRecvTransactions(t *testing.T) {
 }
 
 // This test checks that pending transactions are sent.
-func TestSendTransactions(t *testing.T) {
-	pm := newProtocolManagerForTesting(nil)
+func TestSendTransactions61(t *testing.T) { testSendTransactions(t, 61) }
+func TestSendTransactions62(t *testing.T) { testSendTransactions(t, 62) }
+func TestSendTransactions63(t *testing.T) { testSendTransactions(t, 63) }
+func TestSendTransactions64(t *testing.T) { testSendTransactions(t, 64) }
+
+func testSendTransactions(t *testing.T, protocol int) {
+	pm := newTestProtocolManager(0, nil, nil)
 	defer pm.Stop()
 
 	// Fill the pool with big transactions.
 	const txsize = txsyncPackSize / 10
 	alltxs := make([]*types.Transaction, 100)
 	for nonce := range alltxs {
-		alltxs[nonce] = newtx(testAccount, uint64(nonce), txsize)
+		alltxs[nonce] = newTestTransaction(testAccount, uint64(nonce), txsize)
 	}
 	pm.txpool.AddTransactions(alltxs)
 
@@ -137,7 +149,7 @@ func TestSendTransactions(t *testing.T) {
 		}
 		for n := 0; n < len(alltxs) && !t.Failed(); {
 			var txs []*types.Transaction
-			msg, err := p.ReadMsg()
+			msg, err := p.app.ReadMsg()
 			if err != nil {
 				t.Errorf("%v: read error: %v", p.Peer, err)
 			} else if msg.Code != TxMsg {
@@ -161,97 +173,53 @@ func TestSendTransactions(t *testing.T) {
 		}
 	}
 	for i := 0; i < 3; i++ {
-		p, _ := newTestPeer(pm)
-		p.handshake(t)
+		p, _ := newTestPeer(fmt.Sprintf("peer #%d", i), protocol, pm, true)
 		wg.Add(1)
 		go checktxs(p)
 	}
 	wg.Wait()
 }
 
-// testPeer wraps all peer-related data for tests.
-type testPeer struct {
-	p2p.MsgReadWriter                // writing to the test peer feeds the protocol
-	pipe              *p2p.MsgPipeRW // the protocol read/writes on this end
-	pm                *ProtocolManager
-	*peer
-}
-
-func newProtocolManagerForTesting(txAdded chan<- []*types.Transaction) *ProtocolManager {
-	db, _ := ethdb.NewMemDatabase()
-	core.WriteTestNetGenesisBlock(db, 0)
-	var (
-		em       = new(event.TypeMux)
-		chain, _ = core.NewChainManager(db, core.FakePow{}, em)
-		txpool   = &fakeTxPool{added: txAdded}
-		pm       = NewProtocolManager(NetworkId, em, txpool, core.FakePow{}, chain)
-	)
-	pm.Start()
-	return pm
-}
-
-func newTestPeer(pm *ProtocolManager) (*testPeer, <-chan error) {
-	var id discover.NodeID
-	rand.Read(id[:])
-	rw1, rw2 := p2p.MsgPipe()
-	peer := pm.newPeer(pm.protVer, pm.netId, p2p.NewPeer(id, "test peer", nil), rw2)
-	errc := make(chan error, 1)
-	go func() {
-		pm.newPeerCh <- peer
-		errc <- pm.handle(peer)
-	}()
-	return &testPeer{rw1, rw2, pm, peer}, errc
-}
-
-func (p *testPeer) handshake(t *testing.T) {
-	td, currentBlock, genesis := p.pm.chainman.Status()
-	msg := &statusData{
-		ProtocolVersion: uint32(p.pm.protVer),
-		NetworkId:       uint32(p.pm.netId),
-		TD:              td,
-		CurrentBlock:    currentBlock,
-		GenesisBlock:    genesis,
-	}
-	if err := p2p.ExpectMsg(p, StatusMsg, msg); err != nil {
-		t.Fatalf("status recv: %v", err)
+// Tests that the custom union field encoder and decoder works correctly.
+func TestGetBlockHeadersDataEncodeDecode(t *testing.T) {
+	// Create a "random" hash for testing
+	var hash common.Hash
+	for i, _ := range hash {
+		hash[i] = byte(i)
 	}
-	if err := p2p.Send(p, StatusMsg, msg); err != nil {
-		t.Fatalf("status send: %v", err)
-	}
-}
-
-func (p *testPeer) close() {
-	p.pipe.Close()
-}
+	// Assemble some table driven tests
+	tests := []struct {
+		packet *getBlockHeadersData
+		fail   bool
+	}{
+		// Providing the origin as either a hash or a number should both work
+		{fail: false, packet: &getBlockHeadersData{Origin: hashOrNumber{Number: 314}}},
+		{fail: false, packet: &getBlockHeadersData{Origin: hashOrNumber{Hash: hash}}},
 
-type fakeTxPool struct {
-	// all transactions are collected.
-	mu  sync.Mutex
-	all []*types.Transaction
-	// if added is non-nil, it receives added transactions.
-	added chan<- []*types.Transaction
-}
+		// Providing arbitrary query field should also work
+		{fail: false, packet: &getBlockHeadersData{Origin: hashOrNumber{Number: 314}, Amount: 314, Skip: 1, Reverse: true}},
+		{fail: false, packet: &getBlockHeadersData{Origin: hashOrNumber{Hash: hash}, Amount: 314, Skip: 1, Reverse: true}},
 
-func (pool *fakeTxPool) AddTransactions(txs []*types.Transaction) {
-	pool.mu.Lock()
-	defer pool.mu.Unlock()
-	pool.all = append(pool.all, txs...)
-	if pool.added != nil {
-		pool.added <- txs
+		// Providing both the origin hash and origin number must fail
+		{fail: true, packet: &getBlockHeadersData{Origin: hashOrNumber{Hash: hash, Number: 314}}},
+	}
+	// Iterate over each of the tests and try to encode and then decode
+	for i, tt := range tests {
+		bytes, err := rlp.EncodeToBytes(tt.packet)
+		if err != nil && !tt.fail {
+			t.Fatalf("test %d: failed to encode packet: %v", i, err)
+		} else if err == nil && tt.fail {
+			t.Fatalf("test %d: encode should have failed", i)
+		}
+		if !tt.fail {
+			packet := new(getBlockHeadersData)
+			if err := rlp.DecodeBytes(bytes, packet); err != nil {
+				t.Fatalf("test %d: failed to decode packet: %v", i, err)
+			}
+			if packet.Origin.Hash != tt.packet.Origin.Hash || packet.Origin.Number != tt.packet.Origin.Number || packet.Amount != tt.packet.Amount ||
+				packet.Skip != tt.packet.Skip || packet.Reverse != tt.packet.Reverse {
+				t.Fatalf("test %d: encode decode mismatch: have %+v, want %+v", i, packet, tt.packet)
+			}
+		}
 	}
-}
-
-func (pool *fakeTxPool) GetTransactions() types.Transactions {
-	pool.mu.Lock()
-	defer pool.mu.Unlock()
-	txs := make([]*types.Transaction, len(pool.all))
-	copy(txs, pool.all)
-	return types.Transactions(txs)
-}
-
-func newtx(from *crypto.Key, nonce uint64, datasize int) *types.Transaction {
-	data := make([]byte, datasize)
-	tx := types.NewTransaction(nonce, common.Address{}, big.NewInt(0), big.NewInt(100000), big.NewInt(0), data)
-	tx, _ = tx.SignECDSA(from.PrivateKey)
-	return tx
 }
diff --git a/ethdb/memory_database.go b/ethdb/memory_database.go
index 70b03dfad..d50f8f9d4 100644
--- a/ethdb/memory_database.go
+++ b/ethdb/memory_database.go
@@ -49,6 +49,14 @@ func (db *MemDatabase) Get(key []byte) ([]byte, error) {
 	return db.db[string(key)], nil
 }
 
+func (db *MemDatabase) Keys() [][]byte {
+	keys := [][]byte{}
+	for key, _ := range db.db {
+		keys = append(keys, []byte(key))
+	}
+	return keys
+}
+
 /*
 func (db *MemDatabase) GetKeys() []*common.Key {
 	data, _ := db.Get([]byte("KeyRing"))
diff --git a/metrics/metrics.go b/metrics/metrics.go
index 6d1a065ed..fcf8b5c32 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -31,8 +31,8 @@ import (
 // MetricsEnabledFlag is the CLI flag name to use to enable metrics collections.
 var MetricsEnabledFlag = "metrics"
 
-// enabled is the flag specifying if metrics are enable or not.
-var enabled = false
+// Enabled is the flag specifying if metrics are enable or not.
+var Enabled = false
 
 // Init enables or disables the metrics system. Since we need this to run before
 // any other code gets to create meters and timers, we'll actually do an ugly hack
@@ -41,7 +41,7 @@ func init() {
 	for _, arg := range os.Args {
 		if strings.TrimLeft(arg, "-") == MetricsEnabledFlag {
 			glog.V(logger.Info).Infof("Enabling metrics collection")
-			enabled = true
+			Enabled = true
 		}
 	}
 }
@@ -49,7 +49,7 @@ func init() {
 // NewMeter create a new metrics Meter, either a real one of a NOP stub depending
 // on the metrics flag.
 func NewMeter(name string) metrics.Meter {
-	if !enabled {
+	if !Enabled {
 		return new(metrics.NilMeter)
 	}
 	return metrics.GetOrRegisterMeter(name, metrics.DefaultRegistry)
@@ -58,7 +58,7 @@ func NewMeter(name string) metrics.Meter {
 // NewTimer create a new metrics Timer, either a real one of a NOP stub depending
 // on the metrics flag.
 func NewTimer(name string) metrics.Timer {
-	if !enabled {
+	if !Enabled {
 		return new(metrics.NilTimer)
 	}
 	return metrics.GetOrRegisterTimer(name, metrics.DefaultRegistry)
@@ -68,7 +68,7 @@ func NewTimer(name string) metrics.Timer {
 // process.
 func CollectProcessMetrics(refresh time.Duration) {
 	// Short circuit if the metrics system is disabled
-	if !enabled {
+	if !Enabled {
 		return
 	}
 	// Create the various data collectors
diff --git a/p2p/metrics.go b/p2p/metrics.go
index f98cac274..98b61901d 100644
--- a/p2p/metrics.go
+++ b/p2p/metrics.go
@@ -38,8 +38,14 @@ type meteredConn struct {
 }
 
 // newMeteredConn creates a new metered connection, also bumping the ingress or
-// egress connection meter.
+// egress connection meter. If the metrics system is disabled, this function
+// returns the original object.
 func newMeteredConn(conn net.Conn, ingress bool) net.Conn {
+	// Short circuit if metrics are disabled
+	if !metrics.Enabled {
+		return conn
+	}
+	// Otherwise bump the connection counters and wrap the connection
 	if ingress {
 		ingressConnectMeter.Mark(1)
 	} else {