p2p, dex: rework connection management (#183)

* p2p, dex: rework connection management
* dex: refresh our node record periodically
* dex: don't send new record event if no new record

11 files changed, 424 insertions, 1084 deletions

diff --git a/dex/backend.go b/dex/backend.go
index b16bdc493..6c5c03861 100644
--- a/dex/backend.go
+++ b/dex/backend.go
@@ -245,7 +245,6 @@ func (s *Dexon) Start(srvr *p2p.Server) error {
 	}
 	// Start the networking layer and the light server if requested
 	s.protocolManager.Start(srvr, maxPeers)
-	s.protocolManager.addSelfRecord()
 	return nil
 }
 
diff --git a/dex/handler.go b/dex/handler.go
index df5516f62..490e1ec33 100644
--- a/dex/handler.go
+++ b/dex/handler.go
@@ -38,6 +38,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"math/rand"
 	"net"
 	"sync"
 	"sync/atomic"
@@ -304,10 +305,6 @@ func (pm *ProtocolManager) Start(srvr p2pServer, maxPeers int) {
 
 }
 
-func (pm *ProtocolManager) addSelfRecord() {
-	pm.nodeTable.AddRecords([]*enr.Record{pm.srvr.Self().Record()})
-}
-
 func (pm *ProtocolManager) Stop() {
 	log.Info("Stopping Ethereum protocol")
 
@@ -1177,10 +1174,27 @@ func (pm *ProtocolManager) finalizedBlockBroadcastLoop() {
 }
 
 func (pm *ProtocolManager) recordBroadcastLoop() {
+	r := rand.New(rand.NewSource(time.Now().Unix()))
+	t := time.NewTimer(0)
+	defer t.Stop()
+
 	for {
 		select {
 		case event := <-pm.recordsCh:
 			pm.BroadcastRecords(event.Records)
+			pm.peers.Refresh()
+
+		case <-t.C:
+			record := pm.srvr.Self().Record()
+			log.Debug("refresh our node record", "seq", record.Seq())
+			pm.nodeTable.AddRecords([]*enr.Record{record})
+
+			// Log current peers connection status.
+			pm.peers.Status()
+
+			// Reset timer.
+			d := 1*time.Minute + time.Duration(r.Int63n(60))*time.Second
+			t.Reset(d)
 
 		// Err() channel will be closed when unsubscribing.
 		case <-pm.recordsSub.Err():
diff --git a/dex/nodetable.go b/dex/nodetable.go
index 12cc9ba46..ba1c28994 100644
--- a/dex/nodetable.go
+++ b/dex/nodetable.go
@@ -52,7 +52,9 @@ func (t *nodeTable) AddRecords(records []*enr.Record) {
 		log.Debug("Add new record to node table", "id", node.ID().String(),
 			"ip", node.IP().String(), "udp", node.UDP(), "tcp", node.TCP())
 	}
-	t.feed.Send(newRecordsEvent{newRecords})
+	if len(newRecords) > 0 {
+		go t.feed.Send(newRecordsEvent{newRecords})
+	}
 }
 
 func (t *nodeTable) Records() []*enr.Record {
diff --git a/dex/peer.go b/dex/peer.go
index 0a67db688..67a59348d 100644
--- a/dex/peer.go
+++ b/dex/peer.go
@@ -37,7 +37,6 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"net"
 	"sync"
 	"time"
 
@@ -105,7 +104,8 @@ const (
 
 	handshakeTimeout = 5 * time.Second
 
-	groupNodeNum = 3
+	groupConnNum     = 3
+	groupConnTimeout = 3 * time.Minute
 )
 
 // PeerInfo represents a short summary of the Ethereum sub-protocol metadata known
@@ -129,6 +129,17 @@ type peerLabel struct {
 	round   uint64
 }
 
+func (p peerLabel) String() string {
+	var t string
+	switch p.set {
+	case dkgset:
+		t = fmt.Sprintf("DKGSet round: %d", p.round)
+	case notaryset:
+		t = fmt.Sprintf("NotarySet round: %d chain: %d", p.round, p.chainID)
+	}
+	return t
+}
+
 type peer struct {
 	id string
 
@@ -711,28 +722,27 @@ type peerSet struct {
 	tab    *nodeTable
 	selfPK string
 
-	srvr          p2pServer
-	gov           governance
-	peer2Labels   map[string]map[peerLabel]struct{}
-	label2Peers   map[peerLabel]map[string]struct{}
-	history       map[uint64]struct{}
-	notaryHistory map[uint64]struct{}
-	dkgHistory    map[uint64]struct{}
+	srvr p2pServer
+	gov  governance
+
+	label2Nodes    map[peerLabel]map[string]*enode.Node
+	directConn     map[peerLabel]struct{}
+	groupConnPeers map[peerLabel]map[string]time.Time
+	allDirectPeers map[string]map[peerLabel]struct{}
 }
 
 // newPeerSet creates a new peer set to track the active participants.
 func newPeerSet(gov governance, srvr p2pServer, tab *nodeTable) *peerSet {
 	return &peerSet{
-		peers:         make(map[string]*peer),
-		gov:           gov,
-		srvr:          srvr,
-		tab:           tab,
-		selfPK:        hex.EncodeToString(crypto.FromECDSAPub(&srvr.GetPrivateKey().PublicKey)),
-		peer2Labels:   make(map[string]map[peerLabel]struct{}),
-		label2Peers:   make(map[peerLabel]map[string]struct{}),
-		history:       make(map[uint64]struct{}),
-		notaryHistory: make(map[uint64]struct{}),
-		dkgHistory:    make(map[uint64]struct{}),
+		peers:          make(map[string]*peer),
+		gov:            gov,
+		srvr:           srvr,
+		tab:            tab,
+		selfPK:         hex.EncodeToString(crypto.FromECDSAPub(&srvr.GetPrivateKey().PublicKey)),
+		label2Nodes:    make(map[peerLabel]map[string]*enode.Node),
+		directConn:     make(map[peerLabel]struct{}),
+		groupConnPeers: make(map[peerLabel]map[string]time.Time),
+		allDirectPeers: make(map[string]map[peerLabel]struct{}),
 	}
 }
 
@@ -832,8 +842,8 @@ func (ps *peerSet) PeersWithoutTx(hash common.Hash) []*peer {
 func (ps *peerSet) PeersWithLabel(label peerLabel) []*peer {
 	ps.lock.RLock()
 	defer ps.lock.RUnlock()
-	list := make([]*peer, 0, len(ps.label2Peers[label]))
-	for id := range ps.label2Peers[label] {
+	list := make([]*peer, 0, len(ps.label2Nodes[label]))
+	for id := range ps.label2Nodes[label] {
 		if p, ok := ps.peers[id]; ok {
 			list = append(list, p)
 		}
@@ -845,8 +855,8 @@ func (ps *peerSet) PeersWithoutVote(hash common.Hash, label peerLabel) []*peer {
 	ps.lock.RLock()
 	defer ps.lock.RUnlock()
 
-	list := make([]*peer, 0, len(ps.label2Peers[label]))
-	for id := range ps.label2Peers[label] {
+	list := make([]*peer, 0, len(ps.label2Nodes[label]))
+	for id := range ps.label2Nodes[label] {
 		if p, ok := ps.peers[id]; ok {
 			if !p.knownVotes.Contains(hash) {
 				list = append(list, p)
@@ -948,345 +958,178 @@ func (ps *peerSet) Close() {
 }
 
 func (ps *peerSet) BuildConnection(round uint64) {
-	ps.lock.Lock()
-	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("BuildConnection: %d", round))
-
-	ps.history[round] = struct{}{}
+	dkgLabel := peerLabel{set: dkgset, round: round}
+	if _, ok := ps.label2Nodes[dkgLabel]; !ok {
+		dkgPKs, err := ps.gov.DKGSet(round)
+		if err != nil {
+			log.Error("get DKG set fail", "round", round, "err", err)
+		}
 
-	dkgPKs, err := ps.gov.DKGSet(round)
-	if err != nil {
-		log.Error("get dkg set fail", "round", round, "err", err)
-	}
+		nodes := ps.pksToNodes(dkgPKs)
+		ps.label2Nodes[dkgLabel] = nodes
 
-	// build dkg connection
-	_, inDKGSet := dkgPKs[ps.selfPK]
-	if inDKGSet {
-		delete(dkgPKs, ps.selfPK)
-		dkgLabel := peerLabel{set: dkgset, round: round}
-		for pk := range dkgPKs {
-			ps.addDirectPeer(pk, dkgLabel)
+		if _, exists := nodes[ps.srvr.Self().ID().String()]; exists {
+			ps.buildDirectConn(dkgLabel)
+		} else {
+			ps.buildGroupConn(dkgLabel)
 		}
 	}
-	var inOneNotarySet bool
-	for cid := uint32(0); cid < ps.gov.GetNumChains(round); cid++ {
-		notaryPKs, err := ps.gov.NotarySet(round, cid)
-		if err != nil {
-			log.Error("get notary set fail",
-				"round", round, "chain id", cid, "err", err)
-			continue
-		}
 
-		label := peerLabel{set: notaryset, chainID: cid, round: round}
-		// not in notary set, add group
-		if _, ok := notaryPKs[ps.selfPK]; !ok {
-			var nodes []*enode.Node
-			for pk := range notaryPKs {
-				node := ps.newNode(pk)
-				nodes = append(nodes, node)
-				ps.addLabel(node, label)
+	for chainID := uint32(0); chainID < ps.gov.GetNumChains(round); chainID++ {
+		notaryLabel := peerLabel{set: notaryset, chainID: chainID, round: round}
+		if _, ok := ps.label2Nodes[notaryLabel]; !ok {
+			notaryPKs, err := ps.gov.NotarySet(round, chainID)
+			if err != nil {
+				log.Error("get notary set fail",
+					"round", round, "chainID", chainID, "err", err)
+				continue
 			}
-			ps.srvr.AddGroup(notarySetName(cid, round), nodes, groupNodeNum)
-			continue
-		}
 
-		delete(notaryPKs, ps.selfPK)
-		for pk := range notaryPKs {
-			ps.addDirectPeer(pk, label)
-		}
-		inOneNotarySet = true
-	}
+			nodes := ps.pksToNodes(notaryPKs)
+			ps.label2Nodes[notaryLabel] = nodes
 
-	// build some connections to DKG nodes
-	if !inDKGSet && inOneNotarySet {
-		var nodes []*enode.Node
-		label := peerLabel{set: dkgset, round: round}
-		for pk := range dkgPKs {
-			node := ps.newNode(pk)
-			nodes = append(nodes, node)
-			ps.addLabel(node, label)
+			if _, exists := nodes[ps.srvr.Self().ID().String()]; exists {
+				ps.buildDirectConn(notaryLabel)
+			} else {
+				ps.buildGroupConn(notaryLabel)
+			}
 		}
-		ps.srvr.AddGroup(dkgSetName(round), nodes, groupNodeNum)
 	}
 }
 
 func (ps *peerSet) ForgetConnection(round uint64) {
 	ps.lock.Lock()
 	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("ForgetConnection: %d", round))
 
-	for r := range ps.history {
-		if r <= round {
-			ps.forgetConnection(round)
-			delete(ps.history, r)
+	for label := range ps.directConn {
+		if label.round <= round {
+			ps.forgetDirectConn(label)
 		}
 	}
-}
-
-func (ps *peerSet) forgetConnection(round uint64) {
-	dkgPKs, err := ps.gov.DKGSet(round)
-	if err != nil {
-		log.Error("get dkg set fail", "round", round, "err", err)
-	}
 
-	_, inDKGSet := dkgPKs[ps.selfPK]
-	if inDKGSet {
-		delete(dkgPKs, ps.selfPK)
-		label := peerLabel{set: dkgset, round: round}
-		for id := range dkgPKs {
-			ps.removeDirectPeer(id, label)
+	for label := range ps.groupConnPeers {
+		if label.round <= round {
+			ps.forgetGroupConn(label)
 		}
 	}
 
-	var inOneNotarySet bool
-	for cid := uint32(0); cid < ps.gov.GetNumChains(round); cid++ {
-		notaryPKs, err := ps.gov.NotarySet(round, cid)
-		if err != nil {
-			log.Error("get notary set fail",
-				"round", round, "chain id", cid, "err", err)
-			continue
+	for label := range ps.label2Nodes {
+		if label.round <= round {
+			delete(ps.label2Nodes, label)
 		}
-
-		label := peerLabel{set: notaryset, chainID: cid, round: round}
-
-		// not in notary set, add group
-		if _, ok := notaryPKs[ps.selfPK]; !ok {
-			var nodes []*enode.Node
-			for id := range notaryPKs {
-				node := ps.newNode(id)
-				nodes = append(nodes, node)
-				ps.removeLabel(node, label)
-			}
-			ps.srvr.RemoveGroup(notarySetName(cid, round))
-			continue
-		}
-
-		delete(notaryPKs, ps.selfPK)
-		for pk := range notaryPKs {
-			ps.removeDirectPeer(pk, label)
-		}
-		inOneNotarySet = true
-	}
-
-	// build some connections to DKG nodes
-	if !inDKGSet && inOneNotarySet {
-		var nodes []*enode.Node
-		label := peerLabel{set: dkgset, round: round}
-		for id := range dkgPKs {
-			node := ps.newNode(id)
-			nodes = append(nodes, node)
-			ps.removeLabel(node, label)
-		}
-		ps.srvr.RemoveGroup(dkgSetName(round))
 	}
 }
 
-func (ps *peerSet) BuildNotaryConn(round uint64) {
+func (ps *peerSet) EnsureGroupConn() {
 	ps.lock.Lock()
 	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("BuildNotaryConn: %d", round))
-
-	if _, ok := ps.notaryHistory[round]; ok {
-		return
-	}
-
-	ps.notaryHistory[round] = struct{}{}
 
-	for chainID := uint32(0); chainID < ps.gov.GetNumChains(round); chainID++ {
-		s, err := ps.gov.NotarySet(round, chainID)
-		if err != nil {
-			log.Error("get notary set fail",
-				"round", round, "chain id", chainID, "err", err)
-			continue
-		}
-
-		// not in notary set, add group
-		if _, ok := s[ps.selfPK]; !ok {
-			var nodes []*enode.Node
-			for id := range s {
-				nodes = append(nodes, ps.newNode(id))
+	now := time.Now()
+	for label, peers := range ps.groupConnPeers {
+		// Remove timeout group conn peer.
+		for id, addtime := range peers {
+			if ps.peers[id] == nil && time.Since(addtime) > groupConnTimeout {
+				ps.removeDirectPeer(id, label)
+				delete(ps.groupConnPeers[label], id)
 			}
-			ps.srvr.AddGroup(notarySetName(chainID, round), nodes, groupNodeNum)
-			continue
-		}
-
-		label := peerLabel{
-			set:     notaryset,
-			chainID: chainID,
-			round:   round,
 		}
-		delete(s, ps.selfPK)
-		for pk := range s {
-			ps.addDirectPeer(pk, label)
-		}
-	}
-}
 
-func (ps *peerSet) dumpPeerLabel(s string) {
-	log.Debug(s, "peer num", len(ps.peers))
-	for id, labels := range ps.peer2Labels {
-		_, ok := ps.peers[id]
-		for label := range labels {
-			log.Debug(s, "connected", ok, "id", id[:16],
-				"round", label.round, "cid", label.chainID, "set", label.set)
+		// Add new group conn peer.
+		for id := range ps.label2Nodes[label] {
+			if len(ps.groupConnPeers[label]) >= groupConnNum {
+				break
+			}
+			ps.groupConnPeers[label][id] = now
+			ps.addDirectPeer(id, label)
 		}
 	}
 }
 
-func (ps *peerSet) ForgetNotaryConn(round uint64) {
+func (ps *peerSet) Refresh() {
 	ps.lock.Lock()
 	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("ForgetNotaryConn: %d", round))
-
-	// forget all the rounds before the given round
-	for r := range ps.notaryHistory {
-		if r <= round {
-			ps.forgetNotaryConn(r)
-			delete(ps.notaryHistory, r)
+	for id := range ps.allDirectPeers {
+		if ps.peers[id] == nil {
+			if node := ps.tab.GetNode(enode.HexID(id)); node != nil {
+				ps.srvr.AddDirectPeer(node)
+			}
 		}
 	}
 }
 
-func (ps *peerSet) forgetNotaryConn(round uint64) {
-	for chainID := uint32(0); chainID < ps.gov.GetNumChains(round); chainID++ {
-		s, err := ps.gov.NotarySet(round, chainID)
-		if err != nil {
-			log.Error("get notary set fail",
-				"round", round, "chain id", chainID, "err", err)
-			continue
-		}
-		if _, ok := s[ps.selfPK]; !ok {
-			ps.srvr.RemoveGroup(notarySetName(chainID, round))
-			continue
-		}
-
-		label := peerLabel{
-			set:     notaryset,
-			chainID: chainID,
-			round:   round,
-		}
-		delete(s, ps.selfPK)
-		for pk := range s {
-			ps.removeDirectPeer(pk, label)
-		}
+func (ps *peerSet) buildDirectConn(label peerLabel) {
+	ps.directConn[label] = struct{}{}
+	for id := range ps.label2Nodes[label] {
+		ps.addDirectPeer(id, label)
 	}
 }
 
-func notarySetName(chainID uint32, round uint64) string {
-	return fmt.Sprintf("%d-%d-notaryset", chainID, round)
-}
-
-func dkgSetName(round uint64) string {
-	return fmt.Sprintf("%d-dkgset", round)
-}
-
-func (ps *peerSet) BuildDKGConn(round uint64) {
-	ps.lock.Lock()
-	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("BuildDKGConn: %d", round))
-	s, err := ps.gov.DKGSet(round)
-	if err != nil {
-		log.Error("get dkg set fail", "round", round)
-		return
-	}
-
-	if _, ok := s[ps.selfPK]; !ok {
-		return
-	}
-	ps.dkgHistory[round] = struct{}{}
-
-	delete(s, ps.selfPK)
-	for pk := range s {
-		ps.addDirectPeer(pk, peerLabel{
-			set:   dkgset,
-			round: round,
-		})
+func (ps *peerSet) forgetDirectConn(label peerLabel) {
+	for id := range ps.label2Nodes[label] {
+		ps.removeDirectPeer(id, label)
 	}
+	delete(ps.directConn, label)
 }
 
-func (ps *peerSet) ForgetDKGConn(round uint64) {
-	ps.lock.Lock()
-	defer ps.lock.Unlock()
-	defer ps.dumpPeerLabel(fmt.Sprintf("ForgetDKGConn: %d", round))
-
-	// forget all the rounds before the given round
-	for r := range ps.dkgHistory {
-		if r <= round {
-			ps.forgetDKGConn(r)
-			delete(ps.dkgHistory, r)
+func (ps *peerSet) buildGroupConn(label peerLabel) {
+	peers := make(map[string]time.Time)
+	now := time.Now()
+	for id := range ps.label2Nodes[label] {
+		peers[id] = now
+		ps.addDirectPeer(id, label)
+		if len(peers) >= groupConnNum {
+			break
 		}
 	}
+	ps.groupConnPeers[label] = peers
 }
 
-func (ps *peerSet) forgetDKGConn(round uint64) {
-	s, err := ps.gov.DKGSet(round)
-	if err != nil {
-		log.Error("get dkg set fail", "round", round)
-		return
+func (ps *peerSet) forgetGroupConn(label peerLabel) {
+	for id := range ps.groupConnPeers[label] {
+		ps.removeDirectPeer(id, label)
 	}
-	if _, ok := s[ps.selfPK]; !ok {
+	delete(ps.groupConnPeers, label)
+}
+
+func (ps *peerSet) addDirectPeer(id string, label peerLabel) {
+	if len(ps.allDirectPeers[id]) > 0 {
+		ps.allDirectPeers[id][label] = struct{}{}
 		return
 	}
+	ps.allDirectPeers[id] = map[peerLabel]struct{}{label: {}}
 
-	delete(s, ps.selfPK)
-	label := peerLabel{
-		set:   dkgset,
-		round: round,
+	node := ps.tab.GetNode(enode.HexID(id))
+	if node == nil {
+		node = ps.label2Nodes[label][id]
 	}
-	for pk := range s {
-		ps.removeDirectPeer(pk, label)
-	}
-}
-
-// make sure the ps.lock is held
-func (ps *peerSet) addDirectPeer(pk string, label peerLabel) {
-	node := ps.newNode(pk)
-	ps.addLabel(node, label)
 	ps.srvr.AddDirectPeer(node)
 }
 
-// make sure the ps.lock is held
-func (ps *peerSet) removeDirectPeer(pk string, label peerLabel) {
-	node := ps.newNode(pk)
-	ps.removeLabel(node, label)
-	if len(ps.peer2Labels[node.ID().String()]) == 0 {
-		ps.srvr.RemoveDirectPeer(node)
+func (ps *peerSet) removeDirectPeer(id string, label peerLabel) {
+	if len(ps.allDirectPeers[id]) == 0 {
+		return
 	}
-}
-
-// make sure the ps.lock is held
-func (ps *peerSet) addLabel(node *enode.Node, label peerLabel) {
-	id := node.ID().String()
 
-	if _, ok := ps.peer2Labels[id]; !ok {
-		ps.peer2Labels[id] = make(map[peerLabel]struct{})
+	delete(ps.allDirectPeers[id], label)
+	if len(ps.allDirectPeers[id]) == 0 {
+		ps.srvr.RemoveDirectPeer(ps.label2Nodes[label][id])
+		delete(ps.allDirectPeers, id)
 	}
-	if _, ok := ps.label2Peers[label]; !ok {
-		ps.label2Peers[label] = make(map[string]struct{})
-	}
-	ps.peer2Labels[id][label] = struct{}{}
-	ps.label2Peers[label][id] = struct{}{}
 }
 
-// make sure the ps.lock is held
-func (ps *peerSet) removeLabel(node *enode.Node, label peerLabel) {
-	id := node.ID().String()
-
-	delete(ps.peer2Labels[id], label)
-	delete(ps.label2Peers[label], id)
-	if len(ps.peer2Labels[id]) == 0 {
-		delete(ps.peer2Labels, id)
-	}
-	if len(ps.label2Peers[label]) == 0 {
-		delete(ps.label2Peers, label)
+func (ps *peerSet) pksToNodes(pks map[string]struct{}) map[string]*enode.Node {
+	nodes := map[string]*enode.Node{}
+	for pk := range pks {
+		n := ps.newEmptyNode(pk)
+		if n.ID() == ps.srvr.Self().ID() {
+			n = ps.srvr.Self()
+		}
+		nodes[n.ID().String()] = n
 	}
+	return nodes
 }
 
-// TODO: improve this by not using pk.
-func (ps *peerSet) newNode(pk string) *enode.Node {
-	var ip net.IP
-	var tcp, udp int
-
+func (ps *peerSet) newEmptyNode(pk string) *enode.Node {
 	b, err := hex.DecodeString(pk)
 	if err != nil {
 		panic(err)
@@ -1296,10 +1139,34 @@ func (ps *peerSet) newNode(pk string) *enode.Node {
 	if err != nil {
 		panic(err)
 	}
+	return enode.NewV4(pubkey, nil, 0, 0)
+}
+
+func (ps *peerSet) Status() {
+	ps.lock.Lock()
+	defer ps.lock.Unlock()
+	for label := range ps.directConn {
+		l := label.String()
+		for id := range ps.label2Nodes[label] {
+			_, ok := ps.peers[id]
+			log.Debug("direct conn", "label", l, "id", id, "connected", ok)
+		}
+	}
+
+	for label, peers := range ps.groupConnPeers {
+		l := label.String()
+		for id := range peers {
+			_, ok := ps.peers[id]
+			log.Debug("group conn", "label", l, "id", id, "connected", ok)
+		}
+	}
 
-	node := ps.tab.GetNode(enode.PubkeyToIDV4(pubkey))
-	if node != nil {
-		return node
+	connected := 0
+	for id := range ps.allDirectPeers {
+		if _, ok := ps.peers[id]; ok {
+			connected++
+		}
 	}
-	return enode.NewV4(pubkey, ip, tcp, udp)
+	log.Debug("all direct peers",
+		"connected", connected, "all", len(ps.allDirectPeers))
 }
diff --git a/dex/peer_test.go b/dex/peer_test.go
index 9caa62d1e..29b4971c5 100644
--- a/dex/peer_test.go
+++ b/dex/peer_test.go
@@ -1,15 +1,16 @@
 package dex
 
 import (
+	"crypto/ecdsa"
 	"encoding/hex"
-	"fmt"
+	"reflect"
 	"testing"
 
 	"github.com/dexon-foundation/dexon/crypto"
 	"github.com/dexon-foundation/dexon/p2p/enode"
 )
 
-func TestPeerSetBuildAndForgetNotaryConn(t *testing.T) {
+func TestPeerSetBuildAndForgetConn(t *testing.T) {
 	key, err := crypto.GenerateKey()
 	if err != nil {
 		t.Fatal(err)
@@ -26,7 +27,7 @@ func TestPeerSetBuildAndForgetNotaryConn(t *testing.T) {
 
 	var nodes []*enode.Node
 	for i := 0; i < 9; i++ {
-		nodes = append(nodes, randomNode())
+		nodes = append(nodes, randomV4CompactNode())
 	}
 
 	round10 := [][]*enode.Node{
@@ -55,445 +56,268 @@ func TestPeerSetBuildAndForgetNotaryConn(t *testing.T) {
 		return newTestNodeSet(m[round][cid]), nil
 	}
 
-	ps := newPeerSet(gov, server, table)
-	peer1 := newDummyPeer(nodes[1])
-	peer2 := newDummyPeer(nodes[2])
-	err = ps.Register(peer1)
-	if err != nil {
-		t.Error(err)
-	}
-	err = ps.Register(peer2)
-	if err != nil {
-		t.Error(err)
-	}
-
-	// build round 10
-	ps.BuildNotaryConn(10)
-
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{notaryset, 0, 10},
-		},
-		nodes[2].ID().String(): {
-			{notaryset, 0, 10},
-		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10}, notaryset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkGroup(server, []string{
-		notarySetName(1, 10),
-		notarySetName(2, 10),
-	})
-	if err != nil {
-		t.Error(err)
+	gov.dkgSetFunc = func(round uint64) (map[string]struct{}, error) {
+		m := map[uint64][]*enode.Node{
+			10: {self, nodes[1], nodes[3]},
+			11: {nodes[1], nodes[2], nodes[5]},
+			12: {self, nodes[3], nodes[5]},
+		}
+		return newTestNodeSet(m[round]), nil
 	}
 
-	// build round 11
-	ps.BuildNotaryConn(11)
+	ps := newPeerSet(gov, server, table)
 
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{notaryset, 0, 10},
-			{notaryset, 0, 11},
+	// build round 10
+	ps.BuildConnection(10)
+	ps.BuildConnection(11)
+	ps.BuildConnection(12)
+
+	expectedlabel2Nodes := map[peerLabel]map[string]*enode.Node{
+		{set: notaryset, round: 10, chainID: 0}: {
+			self.ID().String():     self,
+			nodes[1].ID().String(): nodes[1],
+			nodes[2].ID().String(): nodes[2],
 		},
-		nodes[2].ID().String(): {
-			{notaryset, 0, 10},
-			{notaryset, 2, 11},
+		{set: notaryset, round: 10, chainID: 1}: {
+			nodes[1].ID().String(): nodes[1],
+			nodes[3].ID().String(): nodes[3],
 		},
-		nodes[4].ID().String(): {
-			{notaryset, 2, 11},
+		{set: notaryset, round: 10, chainID: 2}: {
+			nodes[2].ID().String(): nodes[2],
+			nodes[4].ID().String(): nodes[4],
 		},
-		nodes[5].ID().String(): {
-			{notaryset, 0, 11},
+		{set: dkgset, round: 10}: {
+			self.ID().String():     self,
+			nodes[1].ID().String(): nodes[1],
+			nodes[3].ID().String(): nodes[3],
 		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10, 11}, notaryset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(), nodes[4].ID(), nodes[5].ID(),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkGroup(server, []string{
-		notarySetName(1, 10),
-		notarySetName(2, 10),
-		notarySetName(1, 11),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-
-	// build round 12
-	ps.BuildNotaryConn(12)
-
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{notaryset, 0, 10},
-			{notaryset, 0, 11},
+		{set: notaryset, round: 11, chainID: 0}: {
+			self.ID().String():     self,
+			nodes[1].ID().String(): nodes[1],
+			nodes[5].ID().String(): nodes[5],
 		},
-		nodes[2].ID().String(): {
-			{notaryset, 0, 10},
-			{notaryset, 2, 11},
-			{notaryset, 2, 12},
+		{set: notaryset, round: 11, chainID: 1}: {
+			nodes[5].ID().String(): nodes[5],
+			nodes[6].ID().String(): nodes[6],
 		},
-		nodes[3].ID().String(): {
-			{notaryset, 0, 12},
+		{set: notaryset, round: 11, chainID: 2}: {
+			self.ID().String():     self,
+			nodes[2].ID().String(): nodes[2],
+			nodes[4].ID().String(): nodes[4],
 		},
-		nodes[4].ID().String(): {
-			{notaryset, 2, 11},
+		{set: dkgset, round: 11}: {
+			nodes[1].ID().String(): nodes[1],
+			nodes[2].ID().String(): nodes[2],
+			nodes[5].ID().String(): nodes[5],
 		},
-		nodes[5].ID().String(): {
-			{notaryset, 0, 11},
-			{notaryset, 0, 12},
+		{set: notaryset, round: 12, chainID: 0}: {
+			self.ID().String():     self,
+			nodes[3].ID().String(): nodes[3],
+			nodes[5].ID().String(): nodes[5],
 		},
-		nodes[6].ID().String(): {
-			{notaryset, 2, 12},
+		{set: notaryset, round: 12, chainID: 1}: {
+			self.ID().String():     self,
+			nodes[7].ID().String(): nodes[7],
+			nodes[8].ID().String(): nodes[8],
 		},
-		nodes[7].ID().String(): {
-			{notaryset, 1, 12},
+		{set: notaryset, round: 12, chainID: 2}: {
+			self.ID().String():     self,
+			nodes[2].ID().String(): nodes[2],
+			nodes[6].ID().String(): nodes[6],
 		},
-		nodes[8].ID().String(): {
-			{notaryset, 1, 12},
+		{set: dkgset, round: 12}: {
+			self.ID().String():     self,
+			nodes[3].ID().String(): nodes[3],
+			nodes[5].ID().String(): nodes[5],
 		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10, 11, 12}, notaryset)
-	if err != nil {
-		t.Error(err)
 	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(), nodes[3].ID(), nodes[4].ID(),
-		nodes[5].ID(), nodes[6].ID(), nodes[7].ID(), nodes[8].ID(),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkGroup(server, []string{
-		notarySetName(1, 10),
-		notarySetName(2, 10),
-		notarySetName(1, 11),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-
-	// forget round 11
-	ps.ForgetNotaryConn(11)
 
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[2].ID().String(): {
-			{notaryset, 2, 12},
-		},
-		nodes[3].ID().String(): {
-			{notaryset, 0, 12},
-		},
-		nodes[5].ID().String(): {
-			{notaryset, 0, 12},
-		},
-		nodes[6].ID().String(): {
-			{notaryset, 2, 12},
-		},
-		nodes[7].ID().String(): {
-			{notaryset, 1, 12},
-		},
-		nodes[8].ID().String(): {
-			{notaryset, 1, 12},
-		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{12}, notaryset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[2].ID(), nodes[3].ID(),
-		nodes[5].ID(), nodes[6].ID(), nodes[7].ID(), nodes[8].ID(),
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkGroup(server, []string{})
-	if err != nil {
-		t.Error(err)
+	if !reflect.DeepEqual(ps.label2Nodes, expectedlabel2Nodes) {
+		t.Errorf("label2Nodes not match")
 	}
 
-	// forget round 12
-	ps.ForgetNotaryConn(12)
-	err = checkPeer2Labels(ps, map[string][]peerLabel{})
-	if err != nil {
-		t.Error(err)
+	expectedDirectConn := map[peerLabel]struct{}{
+		{set: notaryset, round: 10, chainID: 0}: {},
+		{set: notaryset, round: 11, chainID: 0}: {},
+		{set: notaryset, round: 11, chainID: 2}: {},
+		{set: notaryset, round: 12, chainID: 0}: {},
+		{set: notaryset, round: 12, chainID: 1}: {},
+		{set: notaryset, round: 12, chainID: 2}: {},
+		{set: dkgset, round: 10}:                {},
+		{set: dkgset, round: 12}:                {},
 	}
-	err = checkPeerSetHistory(ps, []uint64{}, notaryset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkGroup(server, []string{})
-	if err != nil {
-		t.Error(err)
-	}
-
-}
 
-func TestPeerSetBuildDKGConn(t *testing.T) {
-	key, err := crypto.GenerateKey()
-	if err != nil {
-		t.Fatal(err)
+	if !reflect.DeepEqual(ps.directConn, expectedDirectConn) {
+		t.Errorf("direct conn not match")
 	}
-	server := newTestP2PServer(key)
-	self := server.Self()
-	table := newNodeTable()
 
-	var nodes []*enode.Node
-	for i := 0; i < 6; i++ {
-		nodes = append(nodes, randomNode())
+	expectedGroupConn := []peerLabel{
+		{set: notaryset, round: 10, chainID: 1},
+		{set: notaryset, round: 10, chainID: 2},
+		{set: notaryset, round: 11, chainID: 1},
+		{set: dkgset, round: 11},
 	}
 
-	gov := &testGovernance{}
-
-	gov.dkgSetFunc = func(round uint64) (map[string]struct{}, error) {
-		m := map[uint64][]*enode.Node{
-			10: {self, nodes[1], nodes[2]},
-			11: {nodes[1], nodes[2], nodes[5]},
-			12: {self, nodes[3], nodes[5]},
-		}
-		return newTestNodeSet(m[round]), nil
+	if len(ps.groupConnPeers) != len(expectedGroupConn) {
+		t.Errorf("group conn peers not match")
 	}
 
-	ps := newPeerSet(gov, server, table)
-	peer1 := newDummyPeer(nodes[1])
-	peer2 := newDummyPeer(nodes[2])
-	err = ps.Register(peer1)
-	if err != nil {
-		t.Error(err)
-	}
-	err = ps.Register(peer2)
-	if err != nil {
-		t.Error(err)
+	for _, l := range expectedGroupConn {
+		if len(ps.groupConnPeers[l]) == 0 {
+			t.Errorf("group conn peers is 0")
+		}
 	}
 
-	// build round 10
-	ps.BuildDKGConn(10)
+	expectedAllDirect := make(map[string]map[peerLabel]struct{})
 
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{dkgset, 0, 10},
-		},
-		nodes[2].ID().String(): {
-			{dkgset, 0, 10},
-		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10}, dkgset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(),
-	})
-	if err != nil {
-		t.Error(err)
+	for l := range ps.directConn {
+		for id := range ps.label2Nodes[l] {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
+			}
+			expectedAllDirect[id][l] = struct{}{}
+		}
 	}
 
-	// build round 11
-	ps.BuildDKGConn(11)
-
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{dkgset, 0, 10},
-		},
-		nodes[2].ID().String(): {
-			{dkgset, 0, 10},
-		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10}, dkgset)
-	if err != nil {
-		t.Error(err)
+	for l, peers := range ps.groupConnPeers {
+		for id := range peers {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
+			}
+			expectedAllDirect[id][l] = struct{}{}
+		}
 	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(),
-	})
-	if err != nil {
-		t.Error(err)
+
+	if !reflect.DeepEqual(ps.allDirectPeers, expectedAllDirect) {
+		t.Errorf("all direct peers not match")
 	}
 
-	// build round 12
-	ps.BuildDKGConn(12)
+	// forget round 11
+	ps.ForgetConnection(11)
 
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[1].ID().String(): {
-			{dkgset, 0, 10},
+	expectedlabel2Nodes = map[peerLabel]map[string]*enode.Node{
+		{set: notaryset, round: 12, chainID: 0}: {
+			self.ID().String():     self,
+			nodes[3].ID().String(): nodes[3],
+			nodes[5].ID().String(): nodes[5],
 		},
-		nodes[2].ID().String(): {
-			{dkgset, 0, 10},
+		{set: notaryset, round: 12, chainID: 1}: {
+			self.ID().String():     self,
+			nodes[7].ID().String(): nodes[7],
+			nodes[8].ID().String(): nodes[8],
 		},
-		nodes[3].ID().String(): {
-			{dkgset, 0, 12},
+		{set: notaryset, round: 12, chainID: 2}: {
+			self.ID().String():     self,
+			nodes[2].ID().String(): nodes[2],
+			nodes[6].ID().String(): nodes[6],
 		},
-		nodes[5].ID().String(): {
-			{dkgset, 0, 12},
+		{set: dkgset, round: 12}: {
+			self.ID().String():     self,
+			nodes[3].ID().String(): nodes[3],
+			nodes[5].ID().String(): nodes[5],
 		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{10, 12}, dkgset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[1].ID(), nodes[2].ID(), nodes[3].ID(), nodes[5].ID(),
-	})
-	if err != nil {
-		t.Error(err)
 	}
 
-	// forget round 11
-	ps.ForgetDKGConn(11)
-
-	err = checkPeer2Labels(ps, map[string][]peerLabel{
-		nodes[3].ID().String(): {
-			{dkgset, 0, 12},
-		},
-		nodes[5].ID().String(): {
-			{dkgset, 0, 12},
-		},
-	})
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkPeerSetHistory(ps, []uint64{12}, dkgset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{
-		nodes[3].ID(), nodes[5].ID(),
-	})
-	if err != nil {
-		t.Error(err)
+	if !reflect.DeepEqual(ps.label2Nodes, expectedlabel2Nodes) {
+		t.Errorf("label2Nodes not match")
 	}
 
-	// forget round 12
-	ps.ForgetDKGConn(12)
-	err = checkPeer2Labels(ps, map[string][]peerLabel{})
-	if err != nil {
-		t.Error(err)
+	expectedDirectConn = map[peerLabel]struct{}{
+		{set: notaryset, round: 12, chainID: 0}: {},
+		{set: notaryset, round: 12, chainID: 1}: {},
+		{set: notaryset, round: 12, chainID: 2}: {},
+		{set: dkgset, round: 12}:                {},
 	}
-	err = checkPeerSetHistory(ps, []uint64{}, dkgset)
-	if err != nil {
-		t.Error(err)
-	}
-	err = checkDirectPeer(server, []enode.ID{})
-	if err != nil {
-		t.Error(err)
+
+	if !reflect.DeepEqual(ps.directConn, expectedDirectConn) {
+		t.Error("direct conn not match")
 	}
-}
 
-func checkPeer2Labels(ps *peerSet, want map[string][]peerLabel) error {
-	if len(ps.peer2Labels) != len(want) {
-		return fmt.Errorf("peer num mismatch: got %d, want %d",
-			len(ps.peer2Labels), len(want))
+	expectedGroupConn = []peerLabel{}
+
+	if len(ps.groupConnPeers) != len(expectedGroupConn) {
+		t.Errorf("group conn peers not match")
 	}
 
-	for peerID, gotLabels := range ps.peer2Labels {
-		wantLabels, ok := want[peerID]
-		if !ok {
-			return fmt.Errorf("peer id %s not exists", peerID)
+	for _, l := range expectedGroupConn {
+		if len(ps.groupConnPeers[l]) == 0 {
+			t.Errorf("group conn peers is 0")
 		}
+	}
 
-		if len(gotLabels) != len(wantLabels) {
-			return fmt.Errorf(
-				"num of labels of peer id %s mismatch: got %d, want %d",
-				peerID, len(gotLabels), len(wantLabels))
+	expectedAllDirect = make(map[string]map[peerLabel]struct{})
+
+	for l := range ps.directConn {
+		for id := range ps.label2Nodes[l] {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
+			}
+			expectedAllDirect[id][l] = struct{}{}
 		}
+	}
 
-		for _, label := range wantLabels {
-			if _, ok := gotLabels[label]; !ok {
-				return fmt.Errorf("label: %+v not exists", label)
+	for l, peers := range ps.groupConnPeers {
+		for id := range peers {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
 			}
+			expectedAllDirect[id][l] = struct{}{}
 		}
 	}
-	return nil
-}
 
-func checkPeerSetHistory(ps *peerSet, want []uint64, set setType) error {
-	var history map[uint64]struct{}
-	switch set {
-	case notaryset:
-		history = ps.notaryHistory
-	case dkgset:
-		history = ps.dkgHistory
-	default:
-		return fmt.Errorf("invalid set: %d", set)
+	if !reflect.DeepEqual(ps.allDirectPeers, expectedAllDirect) {
+		t.Errorf("all direct peers not match")
 	}
 
-	if len(history) != len(want) {
-		return fmt.Errorf("num of history mismatch: got %d, want %d",
-			len(history), len(want))
+	// forget round 12
+	ps.ForgetConnection(12)
+
+	expectedlabel2Nodes = map[peerLabel]map[string]*enode.Node{}
+	if !reflect.DeepEqual(ps.label2Nodes, expectedlabel2Nodes) {
+		t.Errorf("label2Nodes not match")
 	}
 
-	for _, r := range want {
-		if _, ok := history[r]; !ok {
-			return fmt.Errorf("round %d not exists", r)
-		}
+	expectedDirectConn = map[peerLabel]struct{}{}
+
+	if !reflect.DeepEqual(ps.directConn, expectedDirectConn) {
+		t.Error("direct conn not match")
 	}
-	return nil
-}
 
-func checkDirectPeer(srvr *testP2PServer, want []enode.ID) error {
-	if len(srvr.direct) != len(want) {
-		return fmt.Errorf("num of direct peer mismatch: got %d, want %d",
-			len(srvr.direct), len(want))
+	expectedGroupConn = []peerLabel{}
+
+	if len(ps.groupConnPeers) != len(expectedGroupConn) {
+		t.Errorf("group conn peers not match")
 	}
 
-	for _, id := range want {
-		if _, ok := srvr.direct[id]; !ok {
-			return fmt.Errorf("direct peer %s not exists", id.String())
+	for _, l := range expectedGroupConn {
+		if len(ps.groupConnPeers[l]) == 0 {
+			t.Errorf("group conn peers is 0")
 		}
 	}
-	return nil
-}
-func checkGroup(srvr *testP2PServer, want []string) error {
-	if len(srvr.group) != len(want) {
-		return fmt.Errorf("num of group mismatch: got %d, want %d",
-			len(srvr.group), len(want))
+
+	expectedAllDirect = make(map[string]map[peerLabel]struct{})
+
+	for l := range ps.directConn {
+		for id := range ps.label2Nodes[l] {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
+			}
+			expectedAllDirect[id][l] = struct{}{}
+		}
 	}
 
-	for _, name := range want {
-		if _, ok := srvr.group[name]; !ok {
-			return fmt.Errorf("group %s not exists", name)
+	for l, peers := range ps.groupConnPeers {
+		for id := range peers {
+			if expectedAllDirect[id] == nil {
+				expectedAllDirect[id] = make(map[peerLabel]struct{})
+			}
+			expectedAllDirect[id][l] = struct{}{}
 		}
 	}
-	return nil
+
+	if !reflect.DeepEqual(ps.allDirectPeers, expectedAllDirect) {
+		t.Errorf("all direct peers not match")
+	}
 }
 
 func newTestNodeSet(nodes []*enode.Node) map[string]struct{} {
@@ -505,6 +329,14 @@ func newTestNodeSet(nodes []*enode.Node) map[string]struct{} {
 	return m
 }
 
-func newDummyPeer(node *enode.Node) *peer {
-	return &peer{id: node.ID().String()}
+func randomV4CompactNode() *enode.Node {
+	var err error
+	var privkey *ecdsa.PrivateKey
+	for {
+		privkey, err = crypto.GenerateKey()
+		if err == nil {
+			break
+		}
+	}
+	return enode.NewV4(&privkey.PublicKey, nil, 0, 0)
 }
diff --git a/dex/protocol.go b/dex/protocol.go
index 9244b8bb7..0cb00ada6 100644
--- a/dex/protocol.go
+++ b/dex/protocol.go
@@ -169,10 +169,6 @@ type p2pServer interface {
 	AddDirectPeer(*enode.Node)
 
 	RemoveDirectPeer(*enode.Node)
-
-	AddGroup(string, []*enode.Node, uint64)
-
-	RemoveGroup(string)
 }
 
 // statusData is the network packet for the status message.
diff --git a/dex/protocol_test.go b/dex/protocol_test.go
index 5c68785e8..74778cdda 100644
--- a/dex/protocol_test.go
+++ b/dex/protocol_test.go
@@ -18,7 +18,6 @@ package dex
 
 import (
 	"crypto/ecdsa"
-	"encoding/hex"
 	"fmt"
 	"reflect"
 	"sync"
@@ -36,6 +35,7 @@ import (
 	"github.com/dexon-foundation/dexon/crypto"
 	"github.com/dexon-foundation/dexon/dex/downloader"
 	"github.com/dexon-foundation/dexon/p2p"
+	"github.com/dexon-foundation/dexon/p2p/enode"
 	"github.com/dexon-foundation/dexon/p2p/enr"
 	"github.com/dexon-foundation/dexon/rlp"
 )
@@ -553,11 +553,15 @@ func TestSendVote(t *testing.T) {
 		},
 	}
 
+	pm.peers.label2Nodes = make(map[peerLabel]map[string]*enode.Node)
 	for i, tt := range testPeers {
 		p, _ := newTestPeer(fmt.Sprintf("peer #%d", i), dex64, pm, true)
 		if tt.label != nil {
-			b := crypto.FromECDSAPub(p.Node().Pubkey())
-			pm.peers.addDirectPeer(hex.EncodeToString(b), *tt.label)
+			if pm.peers.label2Nodes[*tt.label] == nil {
+				pm.peers.label2Nodes[*tt.label] = make(map[string]*enode.Node)
+			}
+			pm.peers.label2Nodes[*tt.label][p.ID().String()] = p.Node()
+			pm.peers.addDirectPeer(p.ID().String(), *tt.label)
 		}
 		wg.Add(1)
 		go checkvote(p, tt.isReceiver)
diff --git a/p2p/dial.go b/p2p/dial.go
index 909bed863..99acade36 100644
--- a/p2p/dial.go
+++ b/p2p/dial.go
@@ -64,12 +64,6 @@ func (t TCPDialer) Dial(dest *enode.Node) (net.Conn, error) {
 	return t.Dialer.Dial("tcp", addr.String())
 }
 
-type dialGroup struct {
-	name  string
-	nodes map[enode.ID]*enode.Node
-	num   uint64
-}
-
 // dialstate schedules dials and discovery lookups.
 // it get's a chance to compute new tasks on every iteration
 // of the main loop in Server.run.
@@ -85,7 +79,6 @@ type dialstate struct {
 	randomNodes   []*enode.Node // filled from Table
 	static        map[enode.ID]*dialTask
 	direct        map[enode.ID]*dialTask
-	group         map[string]*dialGroup
 	hist          *dialHistory
 
 	start     time.Time     // time when the dialer was first used
@@ -143,7 +136,6 @@ func newDialState(self enode.ID, static []*enode.Node, bootnodes []*enode.Node,
 		netrestrict: netrestrict,
 		static:      make(map[enode.ID]*dialTask),
 		direct:      make(map[enode.ID]*dialTask),
-		group:       make(map[string]*dialGroup),
 		dialing:     make(map[enode.ID]connFlag),
 		bootnodes:   make([]*enode.Node, len(bootnodes)),
 		randomNodes: make([]*enode.Node, maxdyn/2),
@@ -179,14 +171,6 @@ func (s *dialstate) removeDirect(n *enode.Node) {
 	s.hist.remove(n.ID())
 }
 
-func (s *dialstate) addGroup(g *dialGroup) {
-	s.group[g.name] = g
-}
-
-func (s *dialstate) removeGroup(g *dialGroup) {
-	delete(s.group, g.name)
-}
-
 func (s *dialstate) newTasks(nRunning int, peers map[enode.ID]*Peer, now time.Time) []task {
 	if s.start.IsZero() {
 		s.start = now
@@ -244,49 +228,6 @@ func (s *dialstate) newTasks(nRunning int, peers map[enode.ID]*Peer, now time.Ti
 		}
 	}
 
-	// compute connected
-	connected := map[string]map[enode.ID]struct{}{}
-	for _, g := range s.group {
-		connected[g.name] = map[enode.ID]struct{}{}
-	}
-
-	for id := range peers {
-		for _, g := range s.group {
-			if _, ok := g.nodes[id]; ok {
-				connected[g.name][id] = struct{}{}
-			}
-		}
-	}
-
-	for id := range s.dialing {
-		for _, g := range s.group {
-			if _, ok := g.nodes[id]; ok {
-				connected[g.name][id] = struct{}{}
-			}
-		}
-	}
-
-	groupNodes := map[enode.ID]*enode.Node{}
-	for _, g := range s.group {
-		for _, n := range g.nodes {
-			if uint64(len(connected[g.name])) >= g.num {
-				break
-			}
-			err := s.checkDial(n, peers)
-			switch err {
-			case errNotWhitelisted, errSelf:
-				log.Warn("Removing group dial candidate", "id", n.ID(), "addr", &net.TCPAddr{IP: n.IP(), Port: n.TCP()}, "err", err)
-				delete(g.nodes, n.ID())
-			case nil:
-				groupNodes[n.ID()] = n
-				connected[g.name][n.ID()] = struct{}{}
-			}
-		}
-	}
-	for _, n := range groupNodes {
-		addDial(groupDialedConn, n)
-	}
-
 	// If we don't have any peers whatsoever, try to dial a random bootnode. This
 	// scenario is useful for the testnet (and private networks) where the discovery
 	// table might be full of mostly bad peers, making it hard to find good ones.
diff --git a/p2p/dial_test.go b/p2p/dial_test.go
index 35e439798..ab687c2ea 100644
--- a/p2p/dial_test.go
+++ b/p2p/dial_test.go
@@ -611,137 +611,6 @@ func TestDialStateDirectDial(t *testing.T) {
 	})
 }
 
-func TestDialStateGroupDial(t *testing.T) {
-	groups := []*dialGroup{
-		{
-			name: "g1",
-			nodes: map[enode.ID]*enode.Node{
-				uintID(1): newNode(uintID(1), nil),
-				uintID(2): newNode(uintID(2), nil),
-			},
-			num: 2,
-		},
-		{
-			name: "g2",
-			nodes: map[enode.ID]*enode.Node{
-				uintID(2): newNode(uintID(2), nil),
-				uintID(3): newNode(uintID(3), nil),
-				uintID(4): newNode(uintID(4), nil),
-				uintID(5): newNode(uintID(5), nil),
-				uintID(6): newNode(uintID(6), nil),
-			},
-			num: 2,
-		},
-	}
-
-	type groupTest struct {
-		peers   []*Peer
-		dialing map[enode.ID]connFlag
-		ceiling map[string]uint64
-	}
-
-	tests := []groupTest{
-		{
-			peers:   nil,
-			dialing: map[enode.ID]connFlag{},
-			ceiling: map[string]uint64{"g1": 2, "g2": 4},
-		},
-		{
-			peers: []*Peer{
-				{rw: &conn{flags: staticDialedConn, node: newNode(uintID(2), nil)}},
-			},
-			dialing: map[enode.ID]connFlag{
-				uintID(1): staticDialedConn,
-			},
-			ceiling: map[string]uint64{"g1": 2, "g2": 2},
-		},
-		{
-			peers: []*Peer{
-				{rw: &conn{flags: staticDialedConn, node: newNode(uintID(1), nil)}},
-				{rw: &conn{flags: staticDialedConn, node: newNode(uintID(3), nil)}},
-				{rw: &conn{flags: staticDialedConn, node: newNode(uintID(4), nil)}},
-				{rw: &conn{flags: staticDialedConn, node: newNode(uintID(5), nil)}},
-			},
-			dialing: map[enode.ID]connFlag{
-				uintID(2): staticDialedConn,
-			},
-			ceiling: map[string]uint64{"g1": 2, "g2": 4},
-		},
-		{
-			peers: nil,
-			dialing: map[enode.ID]connFlag{
-				uintID(1): staticDialedConn,
-				uintID(2): staticDialedConn,
-				uintID(3): staticDialedConn,
-			},
-			ceiling: map[string]uint64{"g1": 2, "g2": 4},
-		},
-	}
-
-	pm := func(ps []*Peer) map[enode.ID]*Peer {
-		m := make(map[enode.ID]*Peer)
-		for _, p := range ps {
-			m[p.rw.node.ID()] = p
-		}
-		return m
-	}
-
-	run := func(i int, tt groupTest) {
-		d := newDialState(enode.ID{}, nil, nil, fakeTable{}, 0, nil)
-		d.dialing = make(map[enode.ID]connFlag)
-		for k, v := range tt.dialing {
-			d.dialing[k] = v
-		}
-
-		for _, g := range groups {
-			d.addGroup(g)
-		}
-		peermap := pm(tt.peers)
-		new := d.newTasks(len(tt.dialing), peermap, time.Now())
-
-		cnt := map[string]uint64{}
-		for id := range peermap {
-			for _, g := range groups {
-				if _, ok := g.nodes[id]; ok {
-					cnt[g.name]++
-				}
-			}
-		}
-
-		for id := range tt.dialing {
-			for _, g := range groups {
-				if _, ok := g.nodes[id]; ok {
-					cnt[g.name]++
-				}
-			}
-		}
-
-		for _, task := range new {
-			id := task.(*dialTask).dest.ID()
-			for _, g := range groups {
-				if _, ok := g.nodes[id]; ok {
-					cnt[g.name]++
-				}
-			}
-		}
-
-		for _, g := range groups {
-			if cnt[g.name] < g.num {
-				t.Errorf("test %d) group %s peers + dialing + new < num (%d < %d)",
-					i, g.name, cnt[g.name], g.num)
-			}
-			if cnt[g.name] > tt.ceiling[g.name] {
-				t.Errorf("test %d) group %s peers + dialing + new > ceiling (%d > %d)",
-					i, g.name, cnt[g.name], tt.ceiling[g.name])
-			}
-		}
-	}
-
-	for i, tt := range tests {
-		run(i, tt)
-	}
-}
-
 // This test checks that static peers will be redialed immediately if they were re-added to a static list.
 func TestDialStaticAfterReset(t *testing.T) {
 	wantStatic := []*enode.Node{
diff --git a/p2p/server.go b/p2p/server.go
index 36b1721a5..58b76a708 100644
--- a/p2p/server.go
+++ b/p2p/server.go
@@ -182,8 +182,6 @@ type Server struct {
 	removedirect  chan *enode.Node
 	addtrusted    chan *enode.Node
 	removetrusted chan *enode.Node
-	addgroup      chan *dialGroup
-	removegroup   chan *dialGroup
 	posthandshake chan *conn
 	addpeer       chan *conn
 	delpeer       chan peerDrop
@@ -206,7 +204,6 @@ const (
 	dynDialedConn connFlag = 1 << iota
 	staticDialedConn
 	directDialedConn
-	groupDialedConn
 	inboundConn
 	trustedConn
 )
@@ -260,9 +257,6 @@ func (f connFlag) String() string {
 	if f&directDialedConn != 0 {
 		s += "-directdial"
 	}
-	if f&groupDialedConn != 0 {
-		s += "-groupdial"
-	}
 	if f&inboundConn != 0 {
 		s += "-inbound"
 	}
@@ -357,26 +351,6 @@ func (srv *Server) RemoveDirectPeer(node *enode.Node) {
 	}
 }
 
-func (srv *Server) AddGroup(name string, nodes []*enode.Node, num uint64) {
-	m := map[enode.ID]*enode.Node{}
-	for _, node := range nodes {
-		m[node.ID()] = node
-	}
-	g := &dialGroup{name: name, nodes: m, num: num}
-	select {
-	case srv.addgroup <- g:
-	case <-srv.quit:
-	}
-}
-
-func (srv *Server) RemoveGroup(name string) {
-	g := &dialGroup{name: name}
-	select {
-	case srv.removegroup <- g:
-	case <-srv.quit:
-	}
-}
-
 // AddTrustedPeer adds the given node to a reserved whitelist which allows the
 // node to always connect, even if the slot are full.
 func (srv *Server) AddTrustedPeer(node *enode.Node) {
@@ -524,8 +498,6 @@ func (srv *Server) Start() (err error) {
 	srv.removestatic = make(chan *enode.Node)
 	srv.adddirect = make(chan *enode.Node)
 	srv.removedirect = make(chan *enode.Node)
-	srv.addgroup = make(chan *dialGroup)
-	srv.removegroup = make(chan *dialGroup)
 	srv.addtrusted = make(chan *enode.Node)
 	srv.removetrusted = make(chan *enode.Node)
 	srv.peerOp = make(chan peerOpFunc)
@@ -689,8 +661,6 @@ type dialer interface {
 	removeStatic(*enode.Node)
 	addDirect(*enode.Node)
 	removeDirect(*enode.Node)
-	addGroup(*dialGroup)
-	removeGroup(*dialGroup)
 }
 
 func (srv *Server) run(dialstate dialer) {
@@ -699,15 +669,12 @@ func (srv *Server) run(dialstate dialer) {
 	defer srv.nodedb.Close()
 
 	var (
-		peers         = make(map[enode.ID]*Peer)
-		inboundCount  = 0
-		trusted       = make(map[enode.ID]bool, len(srv.TrustedNodes))
-		peerflags     = make(map[enode.ID]connFlag)
-		groupRefCount = make(map[enode.ID]int32)
-		groups        = make(map[string]*dialGroup)
-		taskdone      = make(chan task, maxActiveDialTasks)
-		runningTasks  []task
-		queuedTasks   []task // tasks that can't run yet
+		peers        = make(map[enode.ID]*Peer)
+		inboundCount = 0
+		trusted      = make(map[enode.ID]bool, len(srv.TrustedNodes))
+		taskdone     = make(chan task, maxActiveDialTasks)
+		runningTasks []task
+		queuedTasks  []task // tasks that can't run yet
 	)
 	// Put trusted nodes into a map to speed up checks.
 	// Trusted peers are loaded on startup or added via AddTrustedPeer RPC.
@@ -745,60 +712,6 @@ func (srv *Server) run(dialstate dialer) {
 		}
 	}
 
-	// remember and maintain the connection flags locally
-	setConnFlags := func(id enode.ID, f connFlag, val bool) {
-		if p, ok := peers[id]; ok {
-			p.rw.set(f, val)
-		}
-		if val {
-			peerflags[id] |= f
-		} else {
-			peerflags[id] &= ^f
-		}
-		if peerflags[id] == 0 {
-			delete(peerflags, id)
-		}
-	}
-
-	// Put trusted nodes into a map to speed up checks.
-	// Trusted peers are loaded on startup or added via AddTrustedPeer RPC.
-	for _, n := range srv.TrustedNodes {
-		setConnFlags(n.ID(), trustedConn, true)
-	}
-
-	canDisconnect := func(p *Peer) bool {
-		f, ok := peerflags[p.ID()]
-		if ok && f != 0 {
-			return false
-		}
-		return !p.rw.is(dynDialedConn | inboundConn)
-	}
-
-	removeGroup := func(g *dialGroup) {
-		if gg, ok := groups[g.name]; ok {
-			for id := range gg.nodes {
-				groupRefCount[id]--
-				if groupRefCount[id] == 0 {
-					setConnFlags(id, groupDialedConn, false)
-					delete(groupRefCount, id)
-				}
-			}
-		}
-	}
-
-	addGroup := func(g *dialGroup) {
-		if _, ok := groups[g.name]; ok {
-			removeGroup(groups[g.name])
-		}
-		for id := range g.nodes {
-			groupRefCount[id]++
-			if groupRefCount[id] > 0 {
-				setConnFlags(id, groupDialedConn, true)
-			}
-		}
-		groups[g.name] = g
-	}
-
 running:
 	for {
 		scheduleTasks()
@@ -812,16 +725,14 @@ running:
 			// ephemeral static peer list. Add it to the dialer,
 			// it will keep the node connected.
 			srv.log.Trace("Adding static node", "node", n)
-			setConnFlags(n.ID(), staticDialedConn, true)
 			dialstate.addStatic(n)
 		case n := <-srv.removestatic:
 			// This channel is used by RemovePeer to send a
 			// disconnect request to a peer and begin the
 			// stop keeping the node connected.
 			srv.log.Trace("Removing static node", "node", n)
-			setConnFlags(n.ID(), staticDialedConn, false)
 			dialstate.removeStatic(n)
-			if p, ok := peers[n.ID()]; ok && canDisconnect(p) {
+			if p, ok := peers[n.ID()]; ok {
 				p.Disconnect(DiscRequested)
 			}
 		case n := <-srv.adddirect:
@@ -829,42 +740,36 @@ running:
 			// ephemeral direct peer list. Add it to the dialer,
 			// it will keep the node connected.
 			srv.log.Trace("Adding direct node", "node", n)
-			setConnFlags(n.ID(), directDialedConn, true)
-			if p, ok := peers[n.ID()]; ok {
-				p.rw.set(directDialedConn, true)
-			}
 			dialstate.addDirect(n)
 		case n := <-srv.removedirect:
 			// This channel is used by RemoveDirectPeer to send a
 			// disconnect request to a peer and begin the
 			// stop keeping the node connected.
 			srv.log.Trace("Removing direct node", "node", n)
-			setConnFlags(n.ID(), directDialedConn, false)
+			dialstate.removeDirect(n)
 			if p, ok := peers[n.ID()]; ok {
-				p.rw.set(directDialedConn, false)
-				if !p.rw.is(trustedConn | groupDialedConn) {
-					p.Disconnect(DiscRequested)
-				}
+				p.Disconnect(DiscRequested)
 			}
-			dialstate.removeDirect(n)
-		case g := <-srv.addgroup:
-			srv.log.Trace("Adding group", "group", g)
-			addGroup(g)
-			dialstate.addGroup(g)
-		case g := <-srv.removegroup:
-			srv.log.Trace("Removing group", "group", g)
-			removeGroup(g)
-			dialstate.removeGroup(g)
 		case n := <-srv.addtrusted:
 			// This channel is used by AddTrustedPeer to add an enode
 			// to the trusted node set.
 			srv.log.Trace("Adding trusted node", "node", n)
-			setConnFlags(n.ID(), trustedConn, true)
+			trusted[n.ID()] = true
+			// Mark any already-connected peer as trusted
+			if p, ok := peers[n.ID()]; ok {
+				p.rw.set(trustedConn, true)
+			}
 		case n := <-srv.removetrusted:
 			// This channel is used by RemoveTrustedPeer to remove an enode
 			// from the trusted node set.
 			srv.log.Trace("Removing trusted node", "node", n)
-			setConnFlags(n.ID(), trustedConn, false)
+			if _, ok := trusted[n.ID()]; ok {
+				delete(trusted, n.ID())
+			}
+			// Unmark any already-connected peer as trusted
+			if p, ok := peers[n.ID()]; ok {
+				p.rw.set(trustedConn, false)
+			}
 		case op := <-srv.peerOp:
 			// This channel is used by Peers and PeerCount.
 			op(peers)
@@ -879,8 +784,9 @@ running:
 		case c := <-srv.posthandshake:
 			// A connection has passed the encryption handshake so
 			// the remote identity is known (but hasn't been verified yet).
-			if f, ok := peerflags[c.node.ID()]; ok {
-				c.flags |= f
+			if trusted[c.node.ID()] {
+				// Ensure that the trusted flag is set before checking against MaxPeers.
+				c.flags |= trustedConn
 			}
 			// TODO: track in-progress inbound node IDs (pre-Peer) to avoid dialing them.
 			select {
@@ -962,9 +868,9 @@ func (srv *Server) protoHandshakeChecks(peers map[enode.ID]*Peer, inboundCount i
 
 func (srv *Server) encHandshakeChecks(peers map[enode.ID]*Peer, inboundCount int, c *conn) error {
 	switch {
-	case !c.is(trustedConn|staticDialedConn|directDialedConn|groupDialedConn) && len(peers) >= srv.MaxPeers:
+	case !c.is(trustedConn|staticDialedConn|directDialedConn) && len(peers) >= srv.MaxPeers:
 		return DiscTooManyPeers
-	case !c.is(trustedConn|directDialedConn|groupDialedConn) && c.is(inboundConn) && inboundCount >= srv.maxInboundConns():
+	case !c.is(trustedConn|directDialedConn) && c.is(inboundConn) && inboundCount >= srv.maxInboundConns():
 		return DiscTooManyPeers
 	case peers[c.node.ID()] != nil:
 		return DiscAlreadyConnected
diff --git a/p2p/server_test.go b/p2p/server_test.go
index 8bd113791..734b2a8c1 100644
--- a/p2p/server_test.go
+++ b/p2p/server_test.go
@@ -203,92 +203,6 @@ func TestServerDial(t *testing.T) {
 	}
 }
 
-func TestServerPeerConnFlag(t *testing.T) {
-	srv := &Server{
-		Config: Config{
-			PrivateKey: newkey(),
-			MaxPeers:   10,
-			NoDial:     true,
-		},
-	}
-	if err := srv.Start(); err != nil {
-		t.Fatalf("could not start: %v", err)
-	}
-	defer srv.Stop()
-
-	// inject a peer
-	key := newkey()
-	id := enode.PubkeyToIDV4(&key.PublicKey)
-	node := newNode(id, nil)
-	fd, _ := net.Pipe()
-	c := &conn{
-		node:      node,
-		fd:        fd,
-		transport: newTestTransport(&key.PublicKey, fd),
-		flags:     inboundConn,
-		cont:      make(chan error),
-	}
-	if err := srv.checkpoint(c, srv.addpeer); err != nil {
-		t.Fatalf("could not add conn: %v", err)
-	}
-
-	srv.AddTrustedPeer(node)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | trustedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | trustedConn))
-	}
-
-	srv.AddDirectPeer(node)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | trustedConn | directDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | trustedConn | directDialedConn))
-	}
-
-	srv.AddGroup("g1", []*enode.Node{node}, 1)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | trustedConn | directDialedConn | groupDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | trustedConn | directDialedConn | groupDialedConn))
-	}
-
-	srv.AddGroup("g2", []*enode.Node{node}, 1)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | trustedConn | directDialedConn | groupDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | trustedConn | directDialedConn | groupDialedConn))
-	}
-
-	srv.RemoveTrustedPeer(node)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | directDialedConn | groupDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | directDialedConn | directDialedConn))
-	}
-
-	srv.RemoveDirectPeer(node)
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | groupDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | directDialedConn))
-	}
-
-	srv.RemoveGroup("g1")
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != (inboundConn | groupDialedConn) {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, (inboundConn | directDialedConn))
-	}
-
-	srv.RemoveGroup("g2")
-	srv.Peers() // leverage this function to ensure trusted peer is added
-	if c.flags != inboundConn {
-		t.Errorf("flags mismatch: got %d, want %d",
-			c.flags, inboundConn)
-	}
-}
-
 // This test checks that tasks generated by dialstate are
 // actually executed and taskdone is called for them.
 func TestServerTaskScheduling(t *testing.T) {
@@ -429,10 +343,6 @@ func (tg taskgen) addDirect(*enode.Node) {
 }
 func (tg taskgen) removeDirect(*enode.Node) {
 }
-func (tg taskgen) addGroup(*dialGroup) {
-}
-func (tg taskgen) removeGroup(*dialGroup) {
-}
 
 type testTask struct {
 	index  int