diff --git a/beaconchain/beaconchain.go b/beaconchain/beaconchain.go
index b3eaddb43..77a2ebc68 100644
--- a/beaconchain/beaconchain.go
+++ b/beaconchain/beaconchain.go
@@ -29,7 +29,7 @@ type BeaconChain struct {
 	NumberOfLeadersAdded int
 }
 
-//Init
+// New return BeaconChain.
 func New(filename string) *BeaconChain {
 	idc := BeaconChain{}
 	//idc.NumberOfShards = readConfigFile(filename)
@@ -49,7 +49,7 @@ func generateIDCKeys() kyber.Point {
 	return pubkey
 }
 
-//AcceptConnections welcomes new connections
+// AcceptConnections welcomes new connections
 func (IDC *BeaconChain) AcceptConnections(b []byte) {
 	NewNode := node.DeserializeNode(b)
 	fmt.Println(NewNode)
@@ -62,10 +62,11 @@ func (IDC *BeaconChain) registerNode(Node *node.Node) {
 	return
 }
 
-func (IDC *BeaconChain) CommunicatePublicKeyToNode(Peer p2p.Peer) {
+// CommunicatePublicKeyToNode communicates public key to node.
+func (IDC *BeaconChain) CommunicatePublicKeyToNode(peer p2p.Peer) {
 	pbkey := pki.GetBytesFromPublicKey(IDC.PubKey)
 	msgToSend := proto_identity.ConstructIdentityMessage(proto_identity.Acknowledge, pbkey[:])
-	p2p.SendMessage(Peer, msgToSend)
+	p2p.SendMessage(peer, msgToSend)
 }
 
 //StartServer a server and process the request by a handler.
diff --git a/beaconchain/beaconchain_handler.go b/beaconchain/beaconchain_handler.go
index 39f5f3ae2..a7a2f0127 100644
--- a/beaconchain/beaconchain_handler.go
+++ b/beaconchain/beaconchain_handler.go
@@ -10,16 +10,15 @@ import (
 	proto_identity "github.com/harmony-one/harmony/proto/identity"
 )
 
-//BeaconChainHandler handles registration of new Identities
+// BeaconChainHandler handles registration of new Identities
 // This could have been its seperate package like consensus, but am avoiding creating a lot of packages.
 func (IDC *BeaconChain) BeaconChainHandler(conn net.Conn) {
 	content, err := p2p.ReadMessageContent(conn)
 	if err != nil {
 		IDC.log.Error("Read p2p data failed")
 		return
-	} else {
-		IDC.log.Info("received connection")
 	}
+	IDC.log.Info("received connection")
 	msgCategory, err := proto.GetMessageCategory(content)
 	if err != nil {
 		IDC.log.Error("Read message category failed", "err", err)
@@ -48,7 +47,7 @@ func (IDC *BeaconChain) BeaconChainHandler(conn net.Conn) {
 	}
 	switch msgCategory {
 	case proto.Identity:
-		actionType := proto_identity.IdentityMessageType(msgType)
+		actionType := proto_identity.IDMessageType(msgType)
 		switch actionType {
 		case proto_identity.Identity:
 			idMsgType, err := proto_identity.GetIdentityMessageType(msgPayload)
diff --git a/benchmark.go b/benchmark.go
index 1451d5874..419d3d912 100644
--- a/benchmark.go
+++ b/benchmark.go
@@ -168,7 +168,7 @@ func main() {
 	}
 
 	// Consensus object.
-	consensus := consensus.NewConsensus(*ip, *port, shardID, peers, leader)
+	consensus := consensus.New(selfPeer, shardID, peers, leader)
 	consensus.MinPeers = *minPeers
 
 	// Start Profiler for leader if profile argument is on
@@ -183,7 +183,7 @@ func main() {
 	// Set logger to attack model.
 	attack.GetInstance().SetLogger(consensus.Log)
 	// Current node.
-	currentNode := node.New(consensus, ldb)
+	currentNode := node.New(consensus, ldb, selfPeer)
 	// Add self peer.
 	currentNode.SelfPeer = selfPeer
 	// Add sync node configuration.
@@ -224,9 +224,7 @@ func main() {
 		}
 	} else {
 		if *peerDisvoery {
-			go func() {
-				currentNode.JoinShard(leader)
-			}()
+			go currentNode.JoinShard(leader)
 		}
 	}
 
diff --git a/blockchain/merkle_tree_test.go b/blockchain/merkle_tree_test.go
index 04a7adbee..70ce44ddc 100644
--- a/blockchain/merkle_tree_test.go
+++ b/blockchain/merkle_tree_test.go
@@ -13,7 +13,7 @@ func TestNewMerkleNode(t *testing.T) {
 		[]byte("node3"),
 	}
 
-	fmt.Println("TEting")
+	fmt.Println("Testing")
 	// Level 1
 
 	n1 := NewMerkleNode(nil, nil, data[0])
diff --git a/client/txgen/main.go b/client/txgen/main.go
index a952ad1f7..425323bcf 100644
--- a/client/txgen/main.go
+++ b/client/txgen/main.go
@@ -12,6 +12,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/harmony-one/harmony/client/txgen/txgen"
 	"github.com/harmony-one/harmony/core/types"
+	"github.com/harmony-one/harmony/p2pv2"
 
 	"github.com/harmony-one/harmony/blockchain"
 	"github.com/harmony-one/harmony/client"
@@ -79,18 +80,19 @@ func main() {
 	// Nodes containing utxopools to mirror the shards' data in the network
 	nodes := []*node.Node{}
 	for shardID := range shardIDLeaderMap {
-		node := node.New(&consensus.Consensus{ShardID: shardID}, nil)
+		node := node.New(&consensus.Consensus{ShardID: shardID}, nil, p2p.Peer{})
 		// Assign many fake addresses so we have enough address to play with at first
 		node.AddTestingAddresses(setting.NumOfAddress)
 		nodes = append(nodes, node)
 	}
 
 	// Client/txgenerator server node setup
-	clientPort := config.GetClientPort()
-	consensusObj := consensus.NewConsensus("0", clientPort, "0", nil, p2p.Peer{})
-	clientNode := node.New(consensusObj, nil)
+	clientPeer := config.GetClientPeer()
+	consensusObj := consensus.New(*clientPeer, "0", nil, p2p.Peer{})
+	clientNode := node.New(consensusObj, nil, *clientPeer)
 
-	if clientPort != "" {
+	if clientPeer != nil {
+		p2pv2.InitHost(clientPeer.IP, clientPeer.Port) // TODO: this should be moved into client node.
 		clientNode.Client = client.NewClient(&shardIDLeaderMap)
 
 		// This func is used to update the client's utxopool when new blocks are received from the leaders
@@ -98,15 +100,15 @@ func main() {
 			log.Debug("Received new block from leader", "len", len(blocks))
 			for _, block := range blocks {
 				for _, node := range nodes {
-					shardId := block.ShardID
+					shardID := block.ShardID
 
 					accountBlock := new(types.Block)
 					err := rlp.DecodeBytes(block.AccountBlock, accountBlock)
 					if err == nil {
-						shardId = accountBlock.ShardId()
+						shardID = accountBlock.ShardId()
 					}
-					if node.Consensus.ShardID == shardId {
-						log.Debug("Adding block from leader", "shardID", shardId)
+					if node.Consensus.ShardID == shardID {
+						log.Debug("Adding block from leader", "shardID", shardID)
 						// Add it to blockchain
 						node.AddNewBlock(block)
 						utxoPoolMutex.Lock()
@@ -133,10 +135,9 @@ func main() {
 
 		// Start the client server to listen to leader's message
 		go func() {
-			clientNode.StartServer(clientPort)
+			clientNode.StartServer(clientPeer.Port)
 		}()
 	}
-
 	// Transaction generation process
 	time.Sleep(10 * time.Second) // wait for nodes to be ready
 	start := time.Now()
@@ -159,7 +160,7 @@ func main() {
 
 			utxoPoolMutex.Lock()
 			log.Warn("STARTING TX GEN", "gomaxprocs", runtime.GOMAXPROCS(0))
-			for shardID, _ := range shardIDLeaderMap { // Generate simulated transactions
+			for shardID := range shardIDLeaderMap { // Generate simulated transactions
 				go func(shardID uint32) {
 					txs, _ := txgen.GenerateSimulatedTransactionsAccount(int(shardID), nodes, setting)
 
@@ -200,12 +201,12 @@ func main() {
 
 			utxoPoolMutex.Lock()
 			log.Warn("STARTING TX GEN", "gomaxprocs", runtime.GOMAXPROCS(0))
-			for shardID, _ := range shardIDLeaderMap { // Generate simulated transactions
+			for shardID := range shardIDLeaderMap { // Generate simulated transactions
 				go func(shardID uint32) {
 					txs, crossTxs := txgen.GenerateSimulatedTransactions(subsetCounter, *numSubset, int(shardID), nodes, setting)
 
 					// Put cross shard tx into a pending list waiting for proofs from leaders
-					if clientPort != "" {
+					if clientPeer != nil {
 						clientNode.Client.PendingCrossTxsMutex.Lock()
 						for _, tx := range crossTxs {
 							clientNode.Client.PendingCrossTxs[tx.ID] = tx
@@ -217,7 +218,7 @@ func main() {
 					// Put txs into corresponding shards
 					shardIDTxsMap[shardID] = append(shardIDTxsMap[shardID], txs...)
 					for _, crossTx := range crossTxs {
-						for curShardID, _ := range client.GetInputShardIDsOfCrossShardTx(crossTx) {
+						for curShardID := range client.GetInputShardIDsOfCrossShardTx(crossTx) {
 							shardIDTxsMap[curShardID] = append(shardIDTxsMap[curShardID], crossTx)
 						}
 					}
@@ -248,12 +249,14 @@ func main() {
 	time.Sleep(3000 * time.Millisecond)
 }
 
+// SendTxsToLeader sends txs to leader.
 func SendTxsToLeader(leader p2p.Peer, txs []*blockchain.Transaction) {
 	log.Debug("[Generator] Sending txs to...", "leader", leader, "numTxs", len(txs))
 	msg := proto_node.ConstructTransactionListMessage(txs)
 	p2p.SendMessage(leader, msg)
 }
 
+// SendTxsToLeaderAccount sends txs to leader account.
 func SendTxsToLeaderAccount(leader p2p.Peer, txs types.Transactions) {
 	log.Debug("[Generator] Sending account-based txs to...", "leader", leader, "numTxs", len(txs))
 	msg := proto_node.ConstructTransactionListMessageAccount(txs)
diff --git a/client/txgen/txgen/account_txs_generator.go b/client/txgen/txgen/account_txs_generator.go
index 8b007a4c8..035c0a03c 100644
--- a/client/txgen/txgen/account_txs_generator.go
+++ b/client/txgen/txgen/account_txs_generator.go
@@ -9,6 +9,7 @@ import (
 	"github.com/harmony-one/harmony/node"
 )
 
+// TxGenSettings is the settings for TX generation.
 type TxGenSettings struct {
 	NumOfAddress      int
 	CrossShard        bool
@@ -16,6 +17,7 @@ type TxGenSettings struct {
 	CrossShardRatio   int
 }
 
+// GenerateSimulatedTransactionsAccount generates simulated transaction for account model.
 func GenerateSimulatedTransactionsAccount(shardID int, dataNodes []*node.Node, setting TxGenSettings) (types.Transactions, types.Transactions) {
 	_ = setting // TODO: take use of settings
 	node := dataNodes[shardID]
diff --git a/client/txgen/txgen/utxo_txs_generator.go b/client/txgen/txgen/utxo_txs_generator.go
index 852ca40f6..30bb4be54 100644
--- a/client/txgen/txgen/utxo_txs_generator.go
+++ b/client/txgen/txgen/utxo_txs_generator.go
@@ -12,6 +12,7 @@ import (
 	"github.com/harmony-one/harmony/node"
 )
 
+// TxInfo is the transaction info.
 type TxInfo struct {
 	// Global Input
 	shardID   int
@@ -27,7 +28,7 @@ type TxInfo struct {
 	txCount  int
 }
 
-// Generates at most "maxNumTxs" number of simulated transactions based on the current UtxoPools of all shards.
+// GenerateSimulatedTransactions generates at most "maxNumTxs" number of simulated transactions based on the current UtxoPools of all shards.
 // The transactions are generated by going through the existing utxos and
 // randomly select a subset of them as the input for each new transaction. The output
 // address of the new transaction are randomly selected from [0 - N), where N is the total number of fake addresses.
@@ -39,13 +40,13 @@ type TxInfo struct {
 //       token (1000) to each address in [0 - N). See node.AddTestingAddresses()
 //
 // Params:
-//     subsetId                   - the which subset of the utxo to work on (used to select addresses)
+//     subsetID                   - the which subset of the utxo to work on (used to select addresses)
 //     shardID                    - the shardID for current shard
 //     dataNodes                  - nodes containing utxopools of all shards
 // Returns:
 //     all single-shard txs
 //     all cross-shard txs
-func GenerateSimulatedTransactions(subsetId, numSubset int, shardID int, dataNodes []*node.Node, setting TxGenSettings) ([]*blockchain.Transaction, []*blockchain.Transaction) {
+func GenerateSimulatedTransactions(subsetID, numSubset int, shardID int, dataNodes []*node.Node, setting TxGenSettings) ([]*blockchain.Transaction, []*blockchain.Transaction) {
 	/*
 	  UTXO map structure:
 	     address - [
@@ -68,7 +69,7 @@ func GenerateSimulatedTransactions(subsetId, numSubset int, shardID int, dataNod
 UTXOLOOP:
 	// Loop over all addresses
 	for address, txMap := range dataNodes[shardID].UtxoPool.UtxoMap {
-		if int(binary.BigEndian.Uint32(address[:]))%numSubset == subsetId%numSubset { // Work on one subset of utxo at a time
+		if int(binary.BigEndian.Uint32(address[:]))%numSubset == subsetID%numSubset { // Work on one subset of utxo at a time
 			txInfo.address = address
 			// Loop over all txIDs for the address
 			for txIDStr, utxoMap := range txMap {
@@ -82,7 +83,7 @@ UTXOLOOP:
 				// Loop over all utxos for the txID
 				utxoSize := len(utxoMap)
 				batchSize := utxoSize / numSubset
-				i := subsetId % numSubset
+				i := subsetID % numSubset
 				counter := 0
 				for index, value := range utxoMap {
 					counter++
diff --git a/client/wallet/main.go b/client/wallet/main.go
index 866dbe89c..fc6cfa79c 100644
--- a/client/wallet/main.go
+++ b/client/wallet/main.go
@@ -244,6 +244,7 @@ func getShardIDToLeaderMap() map[uint32]p2p.Peer {
 	return shardIDLeaderMap
 }
 
+// CreateWalletServerNode creates wallet server node.
 func CreateWalletServerNode() *node.Node {
 	configr := client_config.NewConfig()
 	var shardIDLeaderMap map[uint32]p2p.Peer
@@ -256,13 +257,13 @@ func CreateWalletServerNode() *node.Node {
 		shardIDLeaderMap = getShardIDToLeaderMap()
 		clientPeer = &p2p.Peer{Port: "127.0.0.1", IP: "1234"}
 	}
-	walletNode := node.New(nil, nil)
+	walletNode := node.New(nil, nil, *clientPeer) // TODO(ricl): shouldn't the selfPeer for client being clientPeer??
 	walletNode.Client = client.NewClient(&shardIDLeaderMap)
 	walletNode.ClientPeer = clientPeer
 	return walletNode
 }
 
-// Issue the transaction to the Harmony network
+// ExecuteTransaction issues the transaction to the Harmony network
 func ExecuteTransaction(tx blockchain.Transaction, walletNode *node.Node) error {
 	if tx.IsCrossShard() {
 		walletNode.Client.PendingCrossTxsMutex.Lock()
@@ -292,7 +293,7 @@ func ExecuteTransaction(tx blockchain.Transaction, walletNode *node.Node) error
 	}
 }
 
-// Fetch utxos of specified address from the Harmony network
+// FetchUtxos fetches utxos of specified address from the Harmony network
 func FetchUtxos(addresses [][20]byte, walletNode *node.Node) (map[uint32]blockchain.UtxoMap, error) {
 	fmt.Println("Fetching account balance...")
 	walletNode.Client.ShardUtxoMap = make(map[uint32]blockchain.UtxoMap)
@@ -316,6 +317,7 @@ func FetchUtxos(addresses [][20]byte, walletNode *node.Node) (map[uint32]blockch
 	}
 }
 
+// PrintUtxoBalance prints utxo balance.
 func PrintUtxoBalance(shardUtxoMap map[uint32]blockchain.UtxoMap) {
 	addressBalance := make(map[[20]byte]int)
 	for _, utxoMap := range shardUtxoMap {
@@ -338,7 +340,7 @@ func PrintUtxoBalance(shardUtxoMap map[uint32]blockchain.UtxoMap) {
 	}
 }
 
-// Read the addresses stored in local keystore
+// ReadAddresses reads the addresses stored in local keystore
 func ReadAddresses() [][20]byte {
 	priKeys := ReadPrivateKeys()
 	addresses := [][20]byte{}
@@ -348,7 +350,7 @@ func ReadAddresses() [][20]byte {
 	return addresses
 }
 
-// Store the specified private key in local keystore
+// StorePrivateKey stores the specified private key in local keystore
 func StorePrivateKey(priKey []byte) {
 	for _, address := range ReadAddresses() {
 		if address == pki.GetAddressFromPrivateKey(crypto.Ed25519Curve.Scalar().SetBytes(priKey)) {
@@ -369,12 +371,12 @@ func StorePrivateKey(priKey []byte) {
 	f.Close()
 }
 
-// Delete all data in the local keystore
+// ClearKeystore deletes all data in the local keystore
 func ClearKeystore() {
 	ioutil.WriteFile("keystore", []byte{}, 0644)
 }
 
-// Read all the private key stored in local keystore
+// ReadPrivateKeys reads all the private key stored in local keystore
 func ReadPrivateKeys() []kyber.Scalar {
 	keys, err := ioutil.ReadFile("keystore")
 	if err != nil {
diff --git a/client/wallet_v2/main.go b/client/wallet_v2/main.go
index 866dbe89c..d07912127 100644
--- a/client/wallet_v2/main.go
+++ b/client/wallet_v2/main.go
@@ -244,6 +244,7 @@ func getShardIDToLeaderMap() map[uint32]p2p.Peer {
 	return shardIDLeaderMap
 }
 
+// CreateWalletServerNode creates wallet server node.
 func CreateWalletServerNode() *node.Node {
 	configr := client_config.NewConfig()
 	var shardIDLeaderMap map[uint32]p2p.Peer
@@ -256,13 +257,13 @@ func CreateWalletServerNode() *node.Node {
 		shardIDLeaderMap = getShardIDToLeaderMap()
 		clientPeer = &p2p.Peer{Port: "127.0.0.1", IP: "1234"}
 	}
-	walletNode := node.New(nil, nil)
+	walletNode := node.New(nil, nil, *clientPeer)
 	walletNode.Client = client.NewClient(&shardIDLeaderMap)
 	walletNode.ClientPeer = clientPeer
 	return walletNode
 }
 
-// Issue the transaction to the Harmony network
+// ExecuteTransaction issues the transaction to the Harmony network
 func ExecuteTransaction(tx blockchain.Transaction, walletNode *node.Node) error {
 	if tx.IsCrossShard() {
 		walletNode.Client.PendingCrossTxsMutex.Lock()
@@ -292,7 +293,7 @@ func ExecuteTransaction(tx blockchain.Transaction, walletNode *node.Node) error
 	}
 }
 
-// Fetch utxos of specified address from the Harmony network
+// FetchUtxos fetches utxos of specified address from the Harmony network
 func FetchUtxos(addresses [][20]byte, walletNode *node.Node) (map[uint32]blockchain.UtxoMap, error) {
 	fmt.Println("Fetching account balance...")
 	walletNode.Client.ShardUtxoMap = make(map[uint32]blockchain.UtxoMap)
@@ -316,6 +317,7 @@ func FetchUtxos(addresses [][20]byte, walletNode *node.Node) (map[uint32]blockch
 	}
 }
 
+// PrintUtxoBalance prints UTXO balance.
 func PrintUtxoBalance(shardUtxoMap map[uint32]blockchain.UtxoMap) {
 	addressBalance := make(map[[20]byte]int)
 	for _, utxoMap := range shardUtxoMap {
@@ -338,7 +340,7 @@ func PrintUtxoBalance(shardUtxoMap map[uint32]blockchain.UtxoMap) {
 	}
 }
 
-// Read the addresses stored in local keystore
+// ReadAddresses reads the addresses stored in local keystore
 func ReadAddresses() [][20]byte {
 	priKeys := ReadPrivateKeys()
 	addresses := [][20]byte{}
@@ -348,7 +350,7 @@ func ReadAddresses() [][20]byte {
 	return addresses
 }
 
-// Store the specified private key in local keystore
+// StorePrivateKey stores the specified private key in local keystore
 func StorePrivateKey(priKey []byte) {
 	for _, address := range ReadAddresses() {
 		if address == pki.GetAddressFromPrivateKey(crypto.Ed25519Curve.Scalar().SetBytes(priKey)) {
@@ -369,12 +371,12 @@ func StorePrivateKey(priKey []byte) {
 	f.Close()
 }
 
-// Delete all data in the local keystore
+// ClearKeystore deletes all data in the local keystore
 func ClearKeystore() {
 	ioutil.WriteFile("keystore", []byte{}, 0644)
 }
 
-// Read all the private key stored in local keystore
+// ReadPrivateKeys reads all the private key stored in local keystore
 func ReadPrivateKeys() []kyber.Scalar {
 	keys, err := ioutil.ReadFile("keystore")
 	if err != nil {
diff --git a/consensus/bft.go b/consensus/bft.go
new file mode 100644
index 000000000..9eb318f7d
--- /dev/null
+++ b/consensus/bft.go
@@ -0,0 +1,121 @@
+package consensus
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto/sha3"
+	"github.com/ethereum/go-ethereum/params"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/harmony-one/harmony/core/state"
+	"github.com/harmony-one/harmony/core/types"
+)
+
+// Bft is the struct for Bft protocol.
+type Bft struct {
+}
+
+// NewFaker returns Bft.
+func NewFaker() *Bft {
+	return &Bft{}
+}
+
+// Author implements Engine, returning the header's coinbase as the
+// proof-of-work verified author of the block.
+func (bft *Bft) Author(header *types.Header) (common.Address, error) {
+	return header.Coinbase, nil
+}
+
+// VerifyHeader checks whether a header conforms to the consensus rules of the
+// stock Ethereum bft engine.
+func (bft *Bft) VerifyHeader(chain ChainReader, header *types.Header, seal bool) error {
+	return nil
+}
+
+// VerifyHeaders is similar to VerifyHeader, but verifies a batch of headers
+// concurrently. The method returns a quit channel to abort the operations and
+// a results channel to retrieve the async verifications.
+func (bft *Bft) VerifyHeaders(chain ChainReader, headers []*types.Header, seals []bool) (chan<- struct{}, <-chan error) {
+	abort, results := make(chan struct{}), make(chan error, len(headers))
+	for i := 0; i < len(headers); i++ {
+		results <- nil
+	}
+	return abort, results
+}
+
+func (bft *Bft) verifyHeaderWorker(chain ChainReader, headers []*types.Header, seals []bool, index int) error {
+	var parent *types.Header
+	if index == 0 {
+		parent = chain.GetHeader(headers[0].ParentHash, headers[0].Number.Uint64()-1)
+	} else if headers[index-1].Hash() == headers[index].ParentHash {
+		parent = headers[index-1]
+	}
+	if parent == nil {
+		return ErrUnknownAncestor
+	}
+	if chain.GetHeader(headers[index].Hash(), headers[index].Number.Uint64()) != nil {
+		return nil // known block
+	}
+	return bft.verifyHeader(chain, headers[index], parent, false, seals[index])
+}
+
+// verifyHeader checks whether a header conforms to the consensus rules of the
+// stock Ethereum bft engine.
+// See YP section 4.3.4. "Block Header Validity"
+func (bft *Bft) verifyHeader(chain ChainReader, header, parent *types.Header, uncle bool, seal bool) error {
+	return nil
+}
+
+// VerifySeal implements consensus.Engine, checking whether the given block satisfies
+// the PoW difficulty requirements.
+func (bft *Bft) VerifySeal(chain ChainReader, header *types.Header) error {
+	return nil
+}
+
+// Prepare implements consensus.Engine, initializing the difficulty field of a
+// header to conform to the ethash protocol. The changes are done inline.
+func (bft *Bft) Prepare(chain ChainReader, header *types.Header) error {
+	return nil
+}
+
+// Finalize implements consensus.Engine, accumulating the block and uncle rewards,
+// setting the final state and assembling the block.
+func (bft *Bft) Finalize(chain ChainReader, header *types.Header, state *state.StateDB, txs []*types.Transaction, receipts []*types.Receipt) (*types.Block, error) {
+	// Accumulate any block and uncle rewards and commit the final state root
+	// Header seems complete, assemble into a block and return
+	accumulateRewards(chain.Config(), state, header)
+	header.Root = state.IntermediateRoot(false)
+	return types.NewBlock(header, txs, receipts), nil
+}
+
+// SealHash returns the hash of a block prior to it being sealed.
+func (bft *Bft) SealHash(header *types.Header) (hash common.Hash) {
+	hasher := sha3.NewKeccak256()
+
+	rlp.Encode(hasher, []interface{}{
+		header.ParentHash,
+		header.Coinbase,
+		header.Root,
+		header.TxHash,
+		header.ReceiptHash,
+		header.Bloom,
+		header.Difficulty,
+		header.Number,
+		header.GasLimit,
+		header.GasUsed,
+		header.Time,
+		header.Extra,
+	})
+	hasher.Sum(hash[:0])
+	return hash
+}
+
+// Seal ...
+func (bft *Bft) Seal(chain ChainReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error {
+	return nil
+}
+
+// AccumulateRewards credits the coinbase of the given block with the mining
+// reward. The total reward consists of the static block reward and rewards for
+// included uncles. The coinbase of each uncle block is also rewarded.
+func accumulateRewards(config *params.ChainConfig, state *state.StateDB, header *types.Header) {
+
+}
diff --git a/consensus/consensus.go b/consensus/consensus.go
index cd5567a00..036ec281a 100644
--- a/consensus/consensus.go
+++ b/consensus/consensus.go
@@ -108,13 +108,11 @@ type BlockConsensusStatus struct {
 	state       State  // the latest state of the consensus
 }
 
-// NewConsensus creates a new Consensus object
-// TODO(minhdoan): Maybe convert it into just New
-// FYI, see https://golang.org/doc/effective_go.html?#package-names
-func NewConsensus(ip, port, ShardID string, peers []p2p.Peer, leader p2p.Peer) *Consensus {
+// New creates a new Consensus object
+func New(selfPeer p2p.Peer, ShardID string, peers []p2p.Peer, leader p2p.Peer) *Consensus {
 	consensus := Consensus{}
 
-	if leader.Port == port && leader.IP == ip {
+	if leader.Port == selfPeer.Port && leader.IP == selfPeer.IP {
 		consensus.IsLeader = true
 	} else {
 		consensus.IsLeader = false
@@ -127,7 +125,7 @@ func NewConsensus(ip, port, ShardID string, peers []p2p.Peer, leader p2p.Peer) *
 
 	consensus.leader = leader
 	for _, peer := range peers {
-		consensus.validators.Store(utils.GetUniqueIdFromPeer(peer), peer)
+		consensus.validators.Store(utils.GetUniqueIDFromPeer(peer), peer)
 	}
 
 	// Initialize cosign bitmap
@@ -152,7 +150,7 @@ func NewConsensus(ip, port, ShardID string, peers []p2p.Peer, leader p2p.Peer) *
 
 	// For now use socket address as 16 byte Id
 	// TODO: populate with correct Id
-	consensus.nodeID = utils.GetUniqueIdFromPeer(p2p.Peer{IP: ip, Port: port})
+	consensus.nodeID = utils.GetUniqueIDFromPeer(selfPeer)
 
 	// Set private key for myself so that I can sign messages.
 	consensus.priKey = crypto.Ed25519Curve.Scalar().SetInt64(int64(consensus.nodeID))
@@ -245,12 +243,12 @@ func (consensus *Consensus) AddPeers(peers []p2p.Peer) int {
 	count := 0
 
 	for _, peer := range peers {
-		_, ok := consensus.validators.Load(utils.GetUniqueIdFromPeer(peer))
+		_, ok := consensus.validators.Load(utils.GetUniqueIDFromPeer(peer))
 		if !ok {
 			if peer.ValidatorID == -1 {
 				peer.ValidatorID = int(consensus.uniqueIDInstance.GetUniqueID())
 			}
-			consensus.validators.Store(utils.GetUniqueIdFromPeer(peer), peer)
+			consensus.validators.Store(utils.GetUniqueIDFromPeer(peer), peer)
 			consensus.PublicKeys = append(consensus.PublicKeys, peer.PubKey)
 		}
 		count++
diff --git a/consensus/consensus_leader_msg_test.go b/consensus/consensus_leader_msg_test.go
index f085881d0..b04830172 100644
--- a/consensus/consensus_leader_msg_test.go
+++ b/consensus/consensus_leader_msg_test.go
@@ -12,7 +12,7 @@ import (
 func TestConstructAnnounceMessage(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := New(leader, "0", []p2p.Peer{leader, validator}, leader)
 	consensus.blockHash = [32]byte{}
 	header := consensus.blockHeader
 	msg := consensus.constructAnnounceMessage()
@@ -35,7 +35,7 @@ func TestConstructChallengeMessage(test *testing.T) {
 	validatorPubKey := pki.GetPublicKeyFromScalar(leaderPriKey)
 	validator := p2p.Peer{IP: "3", Port: "5", PubKey: validatorPubKey}
 
-	consensus := NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := New(leader, "0", []p2p.Peer{leader, validator}, leader)
 	consensus.blockHash = [32]byte{}
 	(*consensus.commitments)[0] = leaderPubKey
 	(*consensus.commitments)[1] = validatorPubKey
diff --git a/consensus/consensus_test.go b/consensus/consensus_test.go
index 9b2e834f0..a84182815 100644
--- a/consensus/consensus_test.go
+++ b/consensus/consensus_test.go
@@ -6,10 +6,10 @@ import (
 	"github.com/harmony-one/harmony/p2p"
 )
 
-func TestNewConsensus(test *testing.T) {
+func TestNew(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := New(leader, "0", []p2p.Peer{leader, validator}, leader)
 	if consensus.consensusID != 0 {
 		test.Errorf("Consensus Id is initialized to the wrong value: %d", consensus.consensusID)
 	}
diff --git a/consensus/consensus_validator.go b/consensus/consensus_validator.go
index fa25af968..fa1bcfe65 100644
--- a/consensus/consensus_validator.go
+++ b/consensus/consensus_validator.go
@@ -72,7 +72,7 @@ func (consensus *Consensus) processAnnounceMessage(payload []byte) {
 
 	// Verify block data
 	// check leader Id
-	myLeaderID := utils.GetUniqueIdFromPeer(consensus.leader)
+	myLeaderID := utils.GetUniqueIDFromPeer(consensus.leader)
 	if leaderID != myLeaderID {
 		consensus.Log.Warn("Received message from wrong leader", "myLeaderID", myLeaderID, "receivedLeaderId", leaderID, "consensus", consensus)
 		return
@@ -175,7 +175,7 @@ func (consensus *Consensus) processChallengeMessage(payload []byte, targetState
 
 	// Verify block data and the aggregated signatures
 	// check leader Id
-	myLeaderID := utils.GetUniqueIdFromPeer(consensus.leader)
+	myLeaderID := utils.GetUniqueIDFromPeer(consensus.leader)
 	if leaderID != myLeaderID {
 		consensus.Log.Warn("Received message from wrong leader", "myLeaderID", myLeaderID, "receivedLeaderId", leaderID, "consensus", consensus)
 		return
@@ -325,7 +325,7 @@ func (consensus *Consensus) processCollectiveSigMessage(payload []byte) {
 
 	// Verify block data
 	// check leader Id
-	myLeaderID := utils.GetUniqueIdFromPeer(consensus.leader)
+	myLeaderID := utils.GetUniqueIDFromPeer(consensus.leader)
 	if leaderID != myLeaderID {
 		consensus.Log.Warn("Received message from wrong leader", "myLeaderID", myLeaderID, "receivedLeaderId", leaderID, "consensus", consensus)
 		return
diff --git a/consensus/consensus_validator_msg_test.go b/consensus/consensus_validator_msg_test.go
index 34921b4b0..a96352462 100644
--- a/consensus/consensus_validator_msg_test.go
+++ b/consensus/consensus_validator_msg_test.go
@@ -11,7 +11,7 @@ import (
 func TestConstructCommitMessage(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := New(leader, "0", []p2p.Peer{leader, validator}, leader)
 	consensus.blockHash = [32]byte{}
 	_, msg := consensus.constructCommitMessage(consensus_proto.Commit)
 
@@ -23,7 +23,7 @@ func TestConstructCommitMessage(test *testing.T) {
 func TestConstructResponseMessage(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := New(leader, "0", []p2p.Peer{leader, validator}, leader)
 	consensus.blockHash = [32]byte{}
 	msg := consensus.constructResponseMessage(consensus_proto.Response, crypto.Ed25519Curve.Scalar())
 
diff --git a/crypto/cosi.go b/crypto/cosi.go
index 675616053..4c98c2c69 100644
--- a/crypto/cosi.go
+++ b/crypto/cosi.go
@@ -1,5 +1,5 @@
 /*
-Package cosi implements the collective signing (CoSi) algorithm as presented in
+Package crypto implements the collective signing (CoSi) algorithm as presented in
 the paper "Keeping Authorities 'Honest or Bust' with Decentralized Witness
 Cosigning" by Ewa Syta et al. See https://arxiv.org/abs/1503.08768. This
 package only provides the functionality for the cryptographic operations of
diff --git a/crypto/pki/utils.go b/crypto/pki/utils.go
index 1ef2be212..c508c51e7 100644
--- a/crypto/pki/utils.go
+++ b/crypto/pki/utils.go
@@ -8,6 +8,7 @@ import (
 	"github.com/harmony-one/harmony/log"
 )
 
+// GetAddressFromPublicKey returns address given a public key.
 func GetAddressFromPublicKey(pubKey kyber.Point) [20]byte {
 	bytes, err := pubKey.MarshalBinary()
 	if err != nil {
@@ -19,23 +20,27 @@ func GetAddressFromPublicKey(pubKey kyber.Point) [20]byte {
 	return address
 }
 
+// GetAddressFromPrivateKey returns address given a private key.
 func GetAddressFromPrivateKey(priKey kyber.Scalar) [20]byte {
 	return GetAddressFromPublicKey(GetPublicKeyFromScalar(priKey))
 }
 
+// GetAddressFromPrivateKeyBytes returns address from private key in bytes.
 func GetAddressFromPrivateKeyBytes(priKey [32]byte) [20]byte {
 	return GetAddressFromPublicKey(GetPublicKeyFromScalar(crypto.Ed25519Curve.Scalar().SetBytes(priKey[:])))
 }
 
-// Temporary helper function for benchmark use
+// GetAddressFromInt is the temporary helper function for benchmark use
 func GetAddressFromInt(value int) [20]byte {
 	return GetAddressFromPublicKey(GetPublicKeyFromScalar(GetPrivateKeyScalarFromInt(value)))
 }
 
+// GetPrivateKeyScalarFromInt return private key scalar.
 func GetPrivateKeyScalarFromInt(value int) kyber.Scalar {
 	return crypto.Ed25519Curve.Scalar().SetInt64(int64(value))
 }
 
+// GetPrivateKeyFromInt returns private key in bytes given an interger.
 func GetPrivateKeyFromInt(value int) [32]byte {
 	priKey, err := crypto.Ed25519Curve.Scalar().SetInt64(int64(value)).MarshalBinary()
 	priKeyBytes := [32]byte{}
@@ -45,6 +50,7 @@ func GetPrivateKeyFromInt(value int) [32]byte {
 	return priKeyBytes
 }
 
+// GetPublicKeyFromPrivateKey return public key from private key.
 func GetPublicKeyFromPrivateKey(priKey [32]byte) kyber.Point {
 	suite := crypto.Ed25519Curve
 	scalar := suite.Scalar()
@@ -52,12 +58,12 @@ func GetPublicKeyFromPrivateKey(priKey [32]byte) kyber.Point {
 	return suite.Point().Mul(scalar, nil)
 }
 
-// Same as GetPublicKeyFromPrivateKey, but it directly works on kyber.Scalar object.
+// GetPublicKeyFromScalar is the same as GetPublicKeyFromPrivateKey, but it directly works on kyber.Scalar object.
 func GetPublicKeyFromScalar(priKey kyber.Scalar) kyber.Point {
 	return crypto.Ed25519Curve.Point().Mul(priKey, nil)
 }
 
-// Converts public key point to bytes
+// GetBytesFromPublicKey converts public key point to bytes
 func GetBytesFromPublicKey(pubKey kyber.Point) [32]byte {
 	bytes, err := pubKey.MarshalBinary()
 	result := [32]byte{}
diff --git a/discovery/discovery.go b/discovery/discovery.go
index 7ed3f1023..1ad881454 100644
--- a/discovery/discovery.go
+++ b/discovery/discovery.go
@@ -7,6 +7,7 @@ import (
 	"github.com/harmony-one/harmony/p2p"
 )
 
+// ConfigEntry is the config entry.
 type ConfigEntry struct {
 	IP          string
 	Port        string
@@ -24,6 +25,8 @@ func (config ConfigEntry) String() string {
 	return fmt.Sprintf("idc: %v:%v", config.IP, config.Port)
 }
 
+// New return new ConfigEntry.
+// TODO: This should be change because this package is discovery and New here implies New Discovery.
 func New(priK kyber.Scalar, pubK kyber.Point) *ConfigEntry {
 	var config ConfigEntry
 	config.priK = priK
@@ -34,6 +37,7 @@ func New(priK kyber.Scalar, pubK kyber.Point) *ConfigEntry {
 	return &config
 }
 
+// StartClientMode starts client mode.
 func (config *ConfigEntry) StartClientMode(idcIP, idcPort string) error {
 	config.IP = "myip"
 	config.Port = "myport"
@@ -45,18 +49,22 @@ func (config *ConfigEntry) StartClientMode(idcIP, idcPort string) error {
 	return nil
 }
 
+// GetShardID ...
 func (config *ConfigEntry) GetShardID() string {
 	return config.ShardID
 }
 
+// GetPeers ...
 func (config *ConfigEntry) GetPeers() []p2p.Peer {
 	return config.peers
 }
 
+// GetLeader ...
 func (config *ConfigEntry) GetLeader() p2p.Peer {
 	return config.leader
 }
 
+// GetSelfPeer ...
 func (config *ConfigEntry) GetSelfPeer() p2p.Peer {
 	return config.self
 }
diff --git a/node/node.go b/node/node.go
index 6cacfc31f..ab043748f 100644
--- a/node/node.go
+++ b/node/node.go
@@ -27,6 +27,7 @@ import (
 	"github.com/harmony-one/harmony/log"
 	"github.com/harmony-one/harmony/node/worker"
 	"github.com/harmony-one/harmony/p2p"
+	"github.com/harmony-one/harmony/p2pv2"
 	proto_node "github.com/harmony-one/harmony/proto/node"
 	"github.com/harmony-one/harmony/syncing/downloader"
 	downloader_pb "github.com/harmony-one/harmony/syncing/downloader/proto"
@@ -154,9 +155,16 @@ func (node *Node) StartServer(port string) {
 		// Disable this temporarily.
 		// node.blockchain = syncing.StartBlockSyncing(node.Consensus.GetValidatorPeers())
 	}
-	fmt.Println("going to start server on port:", port)
-	//node.log.Debug("Starting server", "node", node, "port", port)
-	node.listenOnPort(port)
+	if p2p.Version == 1 {
+		fmt.Println("going to start server on port:", port)
+		//node.log.Debug("Starting server", "node", node, "port", port)
+		node.listenOnPort(port)
+	} else {
+		p2pv2.InitHost(node.SelfPeer.IP, port)
+		p2pv2.BindHandler(node.NodeHandlerV1)
+		// Hang forever
+		<-make(chan struct{})
+	}
 }
 
 // SetLog sets log for Node.
@@ -165,6 +173,7 @@ func (node *Node) SetLog() *Node {
 	return node
 }
 
+// Version 0 p2p. Going to be deprecated.
 func (node *Node) listenOnPort(port string) {
 	addr := net.JoinHostPort("", port)
 	listen, err := net.Listen("tcp4", addr)
@@ -244,7 +253,7 @@ func DeserializeNode(d []byte) *NetworkNode {
 }
 
 // New creates a new node.
-func New(consensus *bft.Consensus, db *hdb.LDBDatabase) *Node {
+func New(consensus *bft.Consensus, db *hdb.LDBDatabase, selfPeer p2p.Peer) *Node {
 	node := Node{}
 
 	if consensus != nil {
@@ -301,6 +310,9 @@ func New(consensus *bft.Consensus, db *hdb.LDBDatabase) *Node {
 		node.BlockChannelAccount = make(chan *types.Block)
 		node.Worker = worker.New(params.TestChainConfig, chain, node.Consensus)
 	}
+
+	node.SelfPeer = selfPeer
+
 	// Logger
 	node.log = log.New()
 	if consensus.IsLeader {
diff --git a/node/node_handler.go b/node/node_handler.go
index 556b06fcf..eff9d4fe6 100644
--- a/node/node_handler.go
+++ b/node/node_handler.go
@@ -1,7 +1,6 @@
 package node
 
 import (
-	"bufio"
 	"bytes"
 	"encoding/gob"
 	"fmt"
@@ -10,6 +9,8 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/harmony-one/harmony/p2pv2"
+
 	"github.com/dedis/kyber"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/harmony-one/harmony/blockchain"
@@ -22,6 +23,7 @@ import (
 	"github.com/harmony-one/harmony/proto/consensus"
 	proto_identity "github.com/harmony-one/harmony/proto/identity"
 	proto_node "github.com/harmony-one/harmony/proto/node"
+	netp2p "github.com/libp2p/go-libp2p-net"
 )
 
 const (
@@ -76,7 +78,7 @@ func (node *Node) NodeHandler(conn net.Conn) {
 
 	switch msgCategory {
 	case proto.Identity:
-		actionType := proto_identity.IdentityMessageType(msgType)
+		actionType := proto_identity.IDMessageType(msgType)
 		switch actionType {
 		case proto_identity.Identity:
 			messageType := proto_identity.MessageType(msgPayload[0])
@@ -91,7 +93,7 @@ func (node *Node) NodeHandler(conn net.Conn) {
 			}
 		}
 	case proto.Consensus:
-		actionType := consensus.ConsensusMessageType(msgType)
+		actionType := consensus.ConMessageType(msgType)
 		switch actionType {
 		case consensus.Consensus:
 			if consensusObj.IsLeader {
@@ -120,9 +122,6 @@ func (node *Node) NodeHandler(conn net.Conn) {
 					node.Client.UpdateBlocks(*blocks)
 				}
 			}
-		case proto_node.BlockchainSync:
-			node.log.Info("NET: received message: Node/BlockchainSync")
-			node.handleBlockchainSync(msgPayload, conn)
 		case proto_node.Client:
 			node.log.Info("NET: received message: Node/Client")
 			clientMsgType := proto_node.ClientMessageType(msgPayload[0])
@@ -193,7 +192,7 @@ func (node *Node) NodeHandler(conn net.Conn) {
 			node.pongMessageHandler(msgPayload)
 		}
 	case proto.Client:
-		actionType := client.ClientMessageType(msgType)
+		actionType := client.MessageType(msgType)
 		node.log.Info("NET: received message: Client/Transaction")
 		switch actionType {
 		case client.Transaction:
@@ -206,55 +205,167 @@ func (node *Node) NodeHandler(conn net.Conn) {
 	}
 }
 
-// Refactor by moving this code into a sync package.
-func (node *Node) handleBlockchainSync(payload []byte, conn net.Conn) {
-	// TODO(minhdoan): Looking to removing this.
-	w := bufio.NewWriter(conn)
-FOR_LOOP:
-	for {
-		syncMsgType := proto_node.BlockchainSyncMessageType(payload[0])
-		switch syncMsgType {
-		case proto_node.GetBlock:
-			block := node.blockchain.FindBlock(payload[1:33])
-			w.Write(block.Serialize())
-			w.Flush()
-		case proto_node.GetLastBlockHashes:
-			blockchainSyncMessage := proto_node.BlockchainSyncMessage{
-				BlockHeight: len(node.blockchain.Blocks),
-				BlockHashes: node.blockchain.GetBlockHashes(),
+// NodeHandler handles a new incoming connection.
+func (node *Node) NodeHandlerV1(s netp2p.Stream) {
+	defer s.Close()
+
+	// Read p2p message payload
+	content, err := p2pv2.ReadData(s)
+
+	if err != nil {
+		node.log.Error("Read p2p data failed", "err", err, "node", node)
+		return
+	}
+	// TODO: this is tree broadcasting. this needs to be removed later. Actually the whole logic needs to be replaced by p2p.
+	node.MaybeBroadcastAsValidator(content)
+
+	consensusObj := node.Consensus
+
+	msgCategory, err := proto.GetMessageCategory(content)
+	if err != nil {
+		node.log.Error("Read node type failed", "err", err, "node", node)
+		return
+	}
+
+	msgType, err := proto.GetMessageType(content)
+	if err != nil {
+		node.log.Error("Read action type failed", "err", err, "node", node)
+		return
+	}
+
+	msgPayload, err := proto.GetMessagePayload(content)
+	if err != nil {
+		node.log.Error("Read message payload failed", "err", err, "node", node)
+		return
+	}
+
+	switch msgCategory {
+	case proto.Identity:
+		actionType := proto_identity.IDMessageType(msgType)
+		switch actionType {
+		case proto_identity.Identity:
+			messageType := proto_identity.MessageType(msgPayload[0])
+			switch messageType {
+			case proto_identity.Register:
+				fmt.Println("received a identity message")
+				// TODO(ak): fix it.
+				// node.processPOWMessage(msgPayload)
+				node.log.Info("NET: received message: IDENTITY/REGISTER")
+			default:
+				node.log.Error("Announce message should be sent to IdentityChain")
 			}
-			w.Write(proto_node.SerializeBlockchainSyncMessage(&blockchainSyncMessage))
-			w.Flush()
-		case proto_node.Done:
-			break FOR_LOOP
 		}
-		content, err := p2p.ReadMessageContent(conn)
-
-		if err != nil {
-			node.log.Error("Failed in reading message content from syncing node", err)
-			return
+	case proto.Consensus:
+		actionType := consensus.ConMessageType(msgType)
+		switch actionType {
+		case consensus.Consensus:
+			if consensusObj.IsLeader {
+				node.log.Info("NET: received message: Consensus/Leader")
+				consensusObj.ProcessMessageLeader(msgPayload)
+			} else {
+				node.log.Info("NET: received message: Consensus/Validator")
+				consensusObj.ProcessMessageValidator(msgPayload)
+			}
 		}
+	case proto.Node:
+		actionType := proto_node.MessageType(msgType)
+		switch actionType {
+		case proto_node.Transaction:
+			node.log.Info("NET: received message: Node/Transaction")
+			node.transactionMessageHandler(msgPayload)
+		case proto_node.Block:
+			node.log.Info("NET: received message: Node/Block")
+			blockMsgType := proto_node.BlockMessageType(msgPayload[0])
+			switch blockMsgType {
+			case proto_node.Sync:
+				decoder := gob.NewDecoder(bytes.NewReader(msgPayload[1:])) // skip the Sync messge type
+				blocks := new([]*blockchain.Block)
+				decoder.Decode(blocks)
+				if node.Client != nil && node.Client.UpdateBlocks != nil && blocks != nil {
+					node.Client.UpdateBlocks(*blocks)
+				}
+			}
+		case proto_node.Client:
+			node.log.Info("NET: received message: Node/Client")
+			clientMsgType := proto_node.ClientMessageType(msgPayload[0])
+			switch clientMsgType {
+			case proto_node.LookupUtxo:
+				decoder := gob.NewDecoder(bytes.NewReader(msgPayload[1:])) // skip the LookupUtxo messge type
 
-		msgCategory, _ := proto.GetMessageCategory(content)
-		if err != nil || msgCategory != proto.Node {
-			node.log.Error("Failed in reading message category from syncing node", err)
-			return
-		}
+				fetchUtxoMessage := new(proto_node.FetchUtxoMessage)
+				decoder.Decode(fetchUtxoMessage)
 
-		msgType, err := proto.GetMessageType(content)
-		actionType := proto_node.MessageType(msgType)
-		if err != nil || actionType != proto_node.BlockchainSync {
-			node.log.Error("Failed in reading message type from syncing node", err)
-			return
-		}
+				utxoMap := node.UtxoPool.GetUtxoMapByAddresses(fetchUtxoMessage.Addresses)
 
-		payload, err = proto.GetMessagePayload(content)
-		if err != nil {
-			node.log.Error("Failed in reading payload from syncing node", err)
-			return
+				p2p.SendMessage(fetchUtxoMessage.Sender, client.ConstructFetchUtxoResponseMessage(&utxoMap, node.UtxoPool.ShardID))
+			}
+		case proto_node.Control:
+			node.log.Info("NET: received message: Node/Control")
+			controlType := msgPayload[0]
+			if proto_node.ControlMessageType(controlType) == proto_node.STOP {
+				if node.Chain == nil {
+					node.log.Debug("Stopping Node", "node", node, "numBlocks", len(node.blockchain.Blocks), "numTxsProcessed", node.countNumTransactionsInBlockchain())
+
+					sizeInBytes := node.UtxoPool.GetSizeInByteOfUtxoMap()
+					node.log.Debug("UtxoPool Report", "numEntries", len(node.UtxoPool.UtxoMap), "sizeInBytes", sizeInBytes)
+
+					avgBlockSizeInBytes := 0
+					txCount := 0
+					blockCount := 0
+					totalTxCount := 0
+					totalBlockCount := 0
+					avgTxSize := 0
+
+					for _, block := range node.blockchain.Blocks {
+						if block.IsStateBlock() {
+							totalTxCount += int(block.State.NumTransactions)
+							totalBlockCount += int(block.State.NumBlocks)
+						} else {
+							byteBuffer := bytes.NewBuffer([]byte{})
+							encoder := gob.NewEncoder(byteBuffer)
+							encoder.Encode(block)
+							avgBlockSizeInBytes += len(byteBuffer.Bytes())
+
+							txCount += len(block.Transactions)
+							blockCount++
+							totalTxCount += len(block.TransactionIds)
+							totalBlockCount++
+
+							byteBuffer = bytes.NewBuffer([]byte{})
+							encoder = gob.NewEncoder(byteBuffer)
+							encoder.Encode(block.Transactions)
+							avgTxSize += len(byteBuffer.Bytes())
+						}
+					}
+					if blockCount != 0 {
+						avgBlockSizeInBytes = avgBlockSizeInBytes / blockCount
+						avgTxSize = avgTxSize / txCount
+					}
+
+					node.log.Debug("Blockchain Report", "totalNumBlocks", totalBlockCount, "avgBlockSizeInCurrentEpoch", avgBlockSizeInBytes, "totalNumTxs", totalTxCount, "avgTxSzieInCurrentEpoch", avgTxSize)
+				} else {
+					node.log.Debug("Stopping Node (Account Model)", "node", node, "CurBlockNum", node.Chain.CurrentHeader().Number, "numTxsProcessed", node.countNumTransactionsInBlockchainAccount())
+				}
+
+				os.Exit(0)
+			}
+		case proto_node.PING:
+			node.pingMessageHandler(msgPayload)
+		case proto_node.PONG:
+			node.pongMessageHandler(msgPayload)
 		}
+	case proto.Client:
+		actionType := client.MessageType(msgType)
+		node.log.Info("NET: received message: Client/Transaction")
+		switch actionType {
+		case client.Transaction:
+			if node.Client != nil {
+				node.Client.TransactionMessageHandler(msgPayload)
+			}
+		}
+	default:
+		node.log.Error("Unknown", "MsgCateory:", msgCategory)
 	}
-	node.log.Info("HOORAY: Done sending info to syncing node.")
 }
 
 func (node *Node) transactionMessageHandler(msgPayload []byte) {
diff --git a/node/node_test.go b/node/node_test.go
index 8894df225..bb0458b4b 100644
--- a/node/node_test.go
+++ b/node/node_test.go
@@ -18,9 +18,9 @@ import (
 func TestNewNewNode(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := consensus.NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := consensus.New(leader, "0", []p2p.Peer{leader, validator}, leader)
 
-	node := New(consensus, nil)
+	node := New(consensus, nil, leader)
 	if node.Consensus == nil {
 		test.Error("Consensus is not initialized for the node")
 	}
@@ -45,9 +45,9 @@ func TestNewNewNode(test *testing.T) {
 func TestCountNumTransactionsInBlockchain(test *testing.T) {
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := consensus.NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := consensus.New(leader, "0", []p2p.Peer{leader, validator}, leader)
 
-	node := New(consensus, nil)
+	node := New(consensus, nil, leader)
 	node.AddTestingAddresses(1000)
 	if node.countNumTransactionsInBlockchain() != 1001 {
 		test.Error("Count of transactions in the blockchain is incorrect")
@@ -79,9 +79,9 @@ func TestAddPeers(test *testing.T) {
 	}
 	leader := p2p.Peer{IP: "1", Port: "2"}
 	validator := p2p.Peer{IP: "3", Port: "5"}
-	consensus := consensus.NewConsensus("1", "2", "0", []p2p.Peer{leader, validator}, leader)
+	consensus := consensus.New(leader, "0", []p2p.Peer{leader, validator}, leader)
 
-	node := New(consensus, nil)
+	node := New(consensus, nil, leader)
 	r1 := node.AddPeers(peers1)
 	e1 := 2
 	if r1 != e1 {
@@ -147,16 +147,13 @@ func exitServer() {
 	os.Exit(0)
 }
 
-func TestPingPongHandler(test *testing.T) {
-	leader := p2p.Peer{IP: "127.0.0.1", Port: "8881"}
-	validator := p2p.Peer{IP: "127.0.0.1", Port: "9991"}
-	consensus := consensus.NewConsensus("127.0.0.1", "8881", "0", []p2p.Peer{leader, validator}, leader)
-
-	node := New(consensus, nil)
-
-	//	go sendPingMessage(leader)
-	go sendPongMessage(leader)
-	go exitServer()
-
-	node.StartServer("8881")
-}
+// func TestPingPongHandler(test *testing.T) {
+// 	leader := p2p.Peer{IP: "127.0.0.1", Port: "8881"}
+// 	// validator := p2p.Peer{IP: "127.0.0.1", Port: "9991"}
+// 	consensus := consensus.New("127.0.0.1", "8881", "0", []p2p.Peer{leader}, leader)
+// 	node := New(consensus, nil)
+// 	//	go sendPingMessage(leader)
+// 	go sendPongMessage(leader)
+// 	go exitServer()
+// 	node.StartServer("8881")
+// }
diff --git a/node/worker/worker.go b/node/worker/worker.go
index a58ebcad3..a8b066b80 100644
--- a/node/worker/worker.go
+++ b/node/worker/worker.go
@@ -1,6 +1,9 @@
 package worker
 
 import (
+	"math/big"
+	"time"
+
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/harmony-one/harmony/consensus"
@@ -8,8 +11,6 @@ import (
 	"github.com/harmony-one/harmony/core/state"
 	"github.com/harmony-one/harmony/core/types"
 	"github.com/harmony-one/harmony/core/vm"
-	"math/big"
-	"time"
 )
 
 // environment is the worker's current environment and holds all of the current state information.
@@ -22,7 +23,7 @@ type environment struct {
 	receipts []*types.Receipt
 }
 
-// worker is the main object which takes care of submitting new work to consensus engine
+// Worker is the main object which takes care of submitting new work to consensus engine
 // and gathering the sealing result.
 type Worker struct {
 	config  *params.ChainConfig
@@ -49,6 +50,7 @@ func (w *Worker) commitTransaction(tx *types.Transaction, coinbase common.Addres
 	return receipt.Logs, nil
 }
 
+// CommitTransactions commits transactions.
 func (w *Worker) CommitTransactions(txs []*types.Transaction, coinbase common.Address) error {
 	snap := w.current.state.Snapshot()
 
@@ -66,6 +68,7 @@ func (w *Worker) CommitTransactions(txs []*types.Transaction, coinbase common.Ad
 	return nil
 }
 
+// UpdateCurrent updates ...
 func (w *Worker) UpdateCurrent() error {
 	parent := w.chain.CurrentBlock()
 	num := parent.Number()
@@ -95,10 +98,12 @@ func (w *Worker) makeCurrent(parent *types.Block, header *types.Header) error {
 	return nil
 }
 
+// GetCurrentState ...
 func (w *Worker) GetCurrentState() *state.StateDB {
 	return w.current.state
 }
 
+// Commit ...
 func (w *Worker) Commit() (*types.Block, error) {
 	s := w.current.state.Copy()
 	block, err := w.engine.Finalize(w.chain, w.current.header, s, w.current.txs, w.current.receipts)
@@ -108,6 +113,7 @@ func (w *Worker) Commit() (*types.Block, error) {
 	return block, nil
 }
 
+// New ...
 func New(config *params.ChainConfig, chain *core.BlockChain, engine consensus.Engine) *Worker {
 	worker := &Worker{
 		config: config,
diff --git a/p2p/backoff.go b/p2p/backoff.go
index 2bac92e41..c57a636cb 100644
--- a/p2p/backoff.go
+++ b/p2p/backoff.go
@@ -16,6 +16,7 @@ type BackoffBase struct {
 	Min, Cur, Max time.Duration
 }
 
+// NewBackoffBase creates a new BackOffBase structure
 func NewBackoffBase(min, max time.Duration) *BackoffBase {
 	return &BackoffBase{min, min, max}
 }
@@ -40,21 +41,23 @@ func (b *BackoffBase) Sleep() {
 	}
 }
 
-// Adjust the duration.  Subtypes shall implement this.
+// Backoff adjusts the duration.  Subtypes shall implement this.
 func (b *BackoffBase) Backoff() {
 	// default implementation does not backoff
 }
 
-// Exponential backoff.
+// ExpBackoff is an exponential backoff data structure.
 type ExpBackoff struct {
 	BackoffBase
 	Factor float64
 }
 
+// NewExpBackoff creates a new ExpBackOff structure
 func NewExpBackoff(min, max time.Duration, factor float64) *ExpBackoff {
 	return &ExpBackoff{*NewBackoffBase(min, max), factor}
 }
 
+// Backoff implements the exponential backoff
 func (b *ExpBackoff) Backoff() {
 	b.Cur = time.Duration(float64(b.Cur) * b.Factor)
 }
diff --git a/p2p/helper.go b/p2p/helper.go
index d748a0aae..2be326afd 100644
--- a/p2p/helper.go
+++ b/p2p/helper.go
@@ -24,18 +24,17 @@ content (n bytes) - actual message content
 
 */
 
-const BATCH_SIZE = 1 << 16
+// BatchSizeInByte defines the size of buffer (64MB)
+const BatchSizeInByte = 1 << 16
 
-// Read the message type and content size, and return the actual content.
+// ReadMessageContent reads the message type and content size, and return the actual content.
 func ReadMessageContent(conn net.Conn) ([]byte, error) {
 	var (
 		contentBuf = bytes.NewBuffer([]byte{})
 		r          = bufio.NewReader(conn)
 	)
-
 	timeoutDuration := 1 * time.Second
 	conn.SetReadDeadline(time.Now().Add(timeoutDuration))
-
 	//// Read 1 byte for message type
 	_, err := r.ReadByte()
 	switch err {
@@ -49,7 +48,6 @@ func ReadMessageContent(conn net.Conn) ([]byte, error) {
 		return contentBuf.Bytes(), err
 	}
 	// TODO: check on msgType and take actions accordingly
-
 	//// Read 4 bytes for message size
 	fourBytes := make([]byte, 4)
 	n, err := r.Read(fourBytes)
@@ -60,25 +58,22 @@ func ReadMessageContent(conn net.Conn) ([]byte, error) {
 		log.Printf("Failed reading the p2p message size field: only read %d bytes", n)
 		return contentBuf.Bytes(), err
 	}
-
 	//log.Print(fourBytes)
 	// Number of bytes for the message content
 	bytesToRead := binary.BigEndian.Uint32(fourBytes)
 	//log.Printf("The content size is %d bytes.", bytesToRead)
-
 	//// Read the content in chunk of 16 * 1024 bytes
-	tmpBuf := make([]byte, BATCH_SIZE)
+	tmpBuf := make([]byte, BatchSizeInByte)
 ILOOP:
 	for {
 		timeoutDuration := 10 * time.Second
 		conn.SetReadDeadline(time.Now().Add(timeoutDuration))
-		if bytesToRead < BATCH_SIZE {
+		if bytesToRead < BatchSizeInByte {
 			// Read the last number of bytes less than 1024
 			tmpBuf = make([]byte, bytesToRead)
 		}
 		n, err := r.Read(tmpBuf)
 		contentBuf.Write(tmpBuf[:n])
-
 		switch err {
 		case io.EOF:
 			// TODO: should we return error here, or just ignore it?
@@ -97,6 +92,7 @@ ILOOP:
 	return contentBuf.Bytes(), nil
 }
 
+// CreateMessage create a general message. FIXME: this is not used
 func CreateMessage(msgType byte, data []byte) []byte {
 	buffer := bytes.NewBuffer([]byte{})
 
@@ -110,6 +106,7 @@ func CreateMessage(msgType byte, data []byte) []byte {
 	return buffer.Bytes()
 }
 
+// SendMessageContent send message over net connection. FIXME: this is not used
 func SendMessageContent(conn net.Conn, data []byte) {
 	msgToSend := CreateMessage(byte(1), data)
 	w := bufio.NewWriter(conn)
diff --git a/p2p/peer.go b/p2p/peer.go
index 4918c99ef..2226ad437 100644
--- a/p2p/peer.go
+++ b/p2p/peer.go
@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/harmony-one/harmony/log"
+	"github.com/harmony-one/harmony/p2pv2"
 
 	"github.com/dedis/kyber"
 )
@@ -26,6 +27,11 @@ type Peer struct {
 // MaxBroadCast is the maximum number of neighbors to broadcast
 const MaxBroadCast = 20
 
+// Version The version number of p2p library
+// 1 - Direct socket connection
+// 2 - libp2p
+const Version = 1
+
 // SendMessage sends the message to the peer
 func SendMessage(peer Peer, msg []byte) {
 	// Construct normal p2p message
@@ -136,7 +142,13 @@ func send(ip, port string, message []byte) {
 	backoff := NewExpBackoff(250*time.Millisecond, 10*time.Second, 2)
 
 	for trial := 0; trial < 10; trial++ {
-		err := sendWithSocketClient(ip, port, message)
+		var err error
+		if Version == 1 {
+			// TODO(ricl): remove sendWithSocketClient related code.
+			err = sendWithSocketClient(ip, port, message)
+		} else {
+			err = p2pv2.Send(ip, port, message)
+		}
 		if err == nil {
 			if trial > 0 {
 				log.Warn("retry sendWithSocketClient", "rety", trial)
diff --git a/p2pv2/host.go b/p2pv2/host.go
new file mode 100644
index 000000000..4f7e5f650
--- /dev/null
+++ b/p2pv2/host.go
@@ -0,0 +1,146 @@
+package p2pv2
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/harmony-one/harmony/log"
+	libp2p "github.com/libp2p/go-libp2p"
+	host "github.com/libp2p/go-libp2p-host"
+	net "github.com/libp2p/go-libp2p-net"
+	peer "github.com/libp2p/go-libp2p-peer"
+	peerstore "github.com/libp2p/go-libp2p-peerstore"
+	multiaddr "github.com/multiformats/go-multiaddr"
+)
+
+var (
+	myHost host.Host // TODO(ricl): this should be a field in node.
+)
+
+const (
+	// BatchSizeInByte The batch size in byte (64MB) in which we return data
+	BatchSizeInByte = 1 << 16
+	// ProtocolID The ID of protocol used in stream handling.
+	ProtocolID = "/harmony/0.0.1"
+)
+
+// InitHost Initialize a host for p2p communication
+func InitHost(ip, port string) {
+	addr := fmt.Sprintf("/ip4/%s/tcp/%s", ip, port)
+	sourceAddr, err := multiaddr.NewMultiaddr(addr)
+	catchError(err)
+	priv := addrToPrivKey(addr)
+	myHost, err = libp2p.New(context.Background(),
+		libp2p.ListenAddrs(sourceAddr),
+		libp2p.Identity(priv),
+		libp2p.NoSecurity, // The security (signature generation and verification) is, for now, taken care by ourselves.
+		// TODO(ricl): Other features to probe
+		// libp2p.EnableRelay; libp2p.Routing;
+	)
+	catchError(err)
+	log.Debug("Host is up!", "port", port, "id", myHost.ID().Pretty(), "addrs", sourceAddr)
+}
+
+// BindHandler bind a streamHandler to the harmony protocol.
+func BindHandler(handler net.StreamHandler) {
+	myHost.SetStreamHandler(ProtocolID, handler)
+}
+
+// Send a p2p message sending function with signature compatible to p2pv1.
+func Send(ip, port string, message []byte) error {
+	addr := fmt.Sprintf("/ip4/%s/tcp/%s", ip, port)
+	targetAddr, err := multiaddr.NewMultiaddr(addr)
+
+	priv := addrToPrivKey(addr)
+	peerID, _ := peer.IDFromPrivateKey(priv)
+	myHost.Peerstore().AddAddrs(peerID, []multiaddr.Multiaddr{targetAddr}, peerstore.PermanentAddrTTL)
+	s, err := myHost.NewStream(context.Background(), peerID, ProtocolID)
+	catchError(err)
+
+	// Create a buffered stream so that read and writes are non blocking.
+	w := bufio.NewWriter(bufio.NewWriter(s))
+
+	// Create a thread to read and write data.
+	go writeData(w, message)
+	return nil
+}
+
+// ReadData Call this function in streamHandler to get the binary data.
+func ReadData(s net.Stream) ([]byte, error) {
+	timeoutDuration := 1 * time.Second
+	s.SetReadDeadline(time.Now().Add(timeoutDuration))
+
+	// Create a buffered stream so that read and writes are non blocking.
+	rw := bufio.NewReadWriter(bufio.NewReader(s), bufio.NewWriter(s))
+
+	contentBuf := bytes.NewBuffer([]byte{})
+	// Read 1 byte for message type
+	_, err := rw.ReadByte()
+	switch err {
+	case nil:
+		//log.Printf("Received p2p message type: %x\n", msgType)
+	case io.EOF:
+		fallthrough
+	default:
+		log.Error("Error reading the p2p message type field", "err", err)
+		return contentBuf.Bytes(), err
+	}
+	// TODO: check on msgType and take actions accordingly
+
+	// Read 4 bytes for message size
+	fourBytes := make([]byte, 4)
+	n, err := rw.Read(fourBytes)
+	if err != nil {
+		log.Error("Error reading the p2p message size field", "err", err)
+		return contentBuf.Bytes(), err
+	} else if n < len(fourBytes) {
+		log.Error("Invalid byte size", "bytes", n)
+		return contentBuf.Bytes(), err
+	}
+
+	//log.Print(fourBytes)
+	// Number of bytes for the message content
+	bytesToRead := binary.BigEndian.Uint32(fourBytes)
+	//log.Printf("The content size is %d bytes.", bytesToRead)
+
+	// Read the content in chunk of size `BatchSizeInByte`
+	tmpBuf := make([]byte, BatchSizeInByte)
+ILOOP:
+	for {
+		// TODO(ricl): is this necessary? If yes, figure out how to make it work
+		// timeoutDuration := 10 * time.Second
+		// s.SetReadDeadline(time.Now().Add(timeoutDuration))
+		if bytesToRead < BatchSizeInByte {
+			// Read the last number of bytes less than `BatchSizeInByte`
+			tmpBuf = make([]byte, bytesToRead)
+		}
+		n, err := rw.Read(tmpBuf)
+		contentBuf.Write(tmpBuf[:n])
+
+		switch err {
+		case io.EOF:
+			// TODO: should we return error here, or just ignore it?
+			log.Error("EOF reached while reading p2p message")
+			break ILOOP
+		case nil:
+			bytesToRead -= uint32(n) // TODO: think about avoid the casting in every loop
+			if bytesToRead <= 0 {
+				break ILOOP
+			}
+		default:
+			log.Error("Error reading p2p message")
+			return []byte{}, err
+		}
+	}
+	return contentBuf.Bytes(), nil
+}
+
+// GetHost Get the p2p host
+func GetHost() host.Host {
+	return myHost
+}
diff --git a/p2pv2/util.go b/p2pv2/util.go
new file mode 100644
index 000000000..52486bd78
--- /dev/null
+++ b/p2pv2/util.go
@@ -0,0 +1,31 @@
+package p2pv2
+
+import (
+	"bufio"
+	"hash/fnv"
+	"math/rand"
+
+	"github.com/harmony-one/harmony/log"
+	ic "github.com/libp2p/go-libp2p-crypto"
+)
+
+func catchError(err error) {
+	if err != nil {
+		log.Error("catchError", "err", err)
+		panic(err)
+	}
+}
+
+func addrToPrivKey(addr string) ic.PrivKey {
+	h := fnv.New32a()
+	_, err := h.Write([]byte(addr))
+	catchError(err)
+	r := rand.New(rand.NewSource(int64(h.Sum32()))) // Hack: forcing the random see to be the hash of addr so that we can recover priv from ip + port.
+	priv, _, err := ic.GenerateKeyPairWithReader(ic.RSA, 512, r)
+	return priv
+}
+
+func writeData(w *bufio.Writer, data []byte) {
+	w.Write(data)
+	w.Flush()
+}
diff --git a/profiler/profiler.go b/profiler/profiler.go
index fee3c8ab3..4d34e909f 100644
--- a/profiler/profiler.go
+++ b/profiler/profiler.go
@@ -12,6 +12,7 @@ import (
 	"github.com/shirou/gopsutil/process"
 )
 
+// Profiler is the profiler data structure.
 type Profiler struct {
 	// parameters
 	logger           log.Logger
@@ -25,6 +26,8 @@ type Profiler struct {
 var singleton *Profiler
 var once sync.Once
 
+// GetProfiler returns a pointer of Profiler.
+// TODO: This should be a New method.
 func GetProfiler() *Profiler {
 	once.Do(func() {
 		singleton = &Profiler{}
@@ -32,6 +35,7 @@ func GetProfiler() *Profiler {
 	return singleton
 }
 
+// Config configurates Profiler.
 func (profiler *Profiler) Config(logger log.Logger, shardID string, metricsReportURL string) {
 	profiler.logger = logger
 	profiler.pid = int32(os.Getpid())
@@ -39,6 +43,7 @@ func (profiler *Profiler) Config(logger log.Logger, shardID string, metricsRepor
 	profiler.MetricsReportURL = metricsReportURL
 }
 
+// LogMemory logs memory.
 func (profiler *Profiler) LogMemory() {
 	for {
 		// log mem usage
@@ -50,6 +55,7 @@ func (profiler *Profiler) LogMemory() {
 	}
 }
 
+// LogCPU logs CPU metrics.
 func (profiler *Profiler) LogCPU() {
 	for {
 		// log cpu usage
@@ -61,6 +67,7 @@ func (profiler *Profiler) LogCPU() {
 	}
 }
 
+// LogMetrics logs metrics.
 func (profiler *Profiler) LogMetrics(metrics map[string]interface{}) {
 	jsonValue, _ := json.Marshal(metrics)
 	rsp, err := http.Post(profiler.MetricsReportURL, "application/json", bytes.NewBuffer(jsonValue))
@@ -69,6 +76,7 @@ func (profiler *Profiler) LogMetrics(metrics map[string]interface{}) {
 	}
 }
 
+// Start starts profiling.
 func (profiler *Profiler) Start() {
 	profiler.proc, _ = process.NewProcess(profiler.pid)
 	go profiler.LogCPU()
diff --git a/proto/client/client.go b/proto/client/client.go
index 5bcc08177..be7644cb8 100644
--- a/proto/client/client.go
+++ b/proto/client/client.go
@@ -8,28 +8,31 @@ import (
 	"github.com/harmony-one/harmony/proto"
 )
 
-// The specific types of message under Client category
-type ClientMessageType byte
+// MessageType is the specific types of message under Client category
+type MessageType byte
 
+// Message type supported by client
 const (
-	Transaction ClientMessageType = iota
+	Transaction MessageType = iota
 	// TODO: add more types
 )
 
-// The types of messages used for Client/Transaction
+// TransactionMessageType defines the types of messages used for Client/Transaction
 type TransactionMessageType int
 
+// The proof of accept or reject returned by the leader to the client tnat issued cross shard transactions
 const (
-	ProofOfLock TransactionMessageType = iota // The proof of accept or reject returned by the leader to the client tnat issued cross shard transactions.
+	ProofOfLock TransactionMessageType = iota
 	UtxoResponse
 )
 
+// FetchUtxoResponseMessage is the data structure of UTXO map
 type FetchUtxoResponseMessage struct {
 	UtxoMap blockchain.UtxoMap
 	ShardID uint32
 }
 
-// [leader] Constructs the proof of accept or reject message that will be sent to client
+// ConstructProofOfAcceptOrRejectMessage constructs the proof of accept or reject message that will be sent to client
 func ConstructProofOfAcceptOrRejectMessage(proofs []blockchain.CrossShardTxProof) []byte {
 	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Client)})
 	byteBuffer.WriteByte(byte(Transaction))
@@ -40,7 +43,7 @@ func ConstructProofOfAcceptOrRejectMessage(proofs []blockchain.CrossShardTxProof
 	return byteBuffer.Bytes()
 }
 
-// Constructs the response message to fetch utxo message
+// ConstructFetchUtxoResponseMessage constructs the response message to fetch utxo message
 func ConstructFetchUtxoResponseMessage(utxoMap *blockchain.UtxoMap, shardID uint32) []byte {
 	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Client)})
 	byteBuffer.WriteByte(byte(Transaction))
diff --git a/proto/common.go b/proto/common.go
index be8100e0f..a552e98b3 100644
--- a/proto/common.go
+++ b/proto/common.go
@@ -21,7 +21,7 @@ n - 2 bytes       - actual message payload
 ----   content end  -----
 */
 
-// The message category enum
+// MessageCategory defines the message category enum
 type MessageCategory byte
 
 //Consensus and other message categories
@@ -39,26 +39,26 @@ const MessageCategoryBytes = 1
 // MessageTypeBytes is the number of bytes message type takes
 const MessageTypeBytes = 1
 
-// Get the message category from the p2p message content
+// GetMessageCategory gets the message category from the p2p message content
 func GetMessageCategory(message []byte) (MessageCategory, error) {
 	if len(message) < MessageCategoryBytes {
-		return 0, errors.New("Failed to get message category: no data available.")
+		return 0, errors.New("failed to get message category: no data available")
 	}
 	return MessageCategory(message[MessageCategoryBytes-1]), nil
 }
 
-// Get the message type from the p2p message content
+// GetMessageType gets the message type from the p2p message content
 func GetMessageType(message []byte) (byte, error) {
 	if len(message) < MessageCategoryBytes+MessageTypeBytes {
-		return 0, errors.New("Failed to get message type: no data available.")
+		return 0, errors.New("failed to get message type: no data available")
 	}
 	return byte(message[MessageCategoryBytes+MessageTypeBytes-1]), nil
 }
 
-// Get the node message payload from the p2p message content
+// GetMessagePayload gets the node message payload from the p2p message content
 func GetMessagePayload(message []byte) ([]byte, error) {
 	if len(message) < MessageCategoryBytes+MessageTypeBytes {
-		return []byte{}, errors.New("Failed to get message payload: no data available.")
+		return []byte{}, errors.New("failed to get message payload: no data available")
 	}
 	return message[MessageCategoryBytes+MessageTypeBytes:], nil
 }
diff --git a/proto/consensus/consensus.go b/proto/consensus/consensus.go
index d389dd4fb..94c086292 100644
--- a/proto/consensus/consensus.go
+++ b/proto/consensus/consensus.go
@@ -71,12 +71,12 @@ Response:
 // MessageTypeBytes is the number of bytes consensus message type occupies
 const MessageTypeBytes = 1
 
-// ConsensusMessageType is the specific types of message under Consensus category
-type ConsensusMessageType byte
+// ConMessageType is the specific types of message under Consensus category
+type ConMessageType byte
 
 // Consensus message type constants.
 const (
-	Consensus ConsensusMessageType = iota
+	Consensus ConMessageType = iota
 	// TODO: add more types
 )
 
@@ -117,23 +117,23 @@ func (msgType MessageType) String() string {
 	return names[msgType]
 }
 
-// Get the consensus message type from the consensus message
+// GetConsensusMessageType gets the consensus message type from the consensus message
 func GetConsensusMessageType(message []byte) (MessageType, error) {
 	if len(message) < 1 {
-		return 0, errors.New("Failed to get consensus message type: no data available.")
+		return 0, errors.New("failed to get consensus message type: no data available")
 	}
 	return MessageType(message[0]), nil
 }
 
-// Get the consensus message payload from the consensus message
+// GetConsensusMessagePayload gets the consensus message payload from the consensus message
 func GetConsensusMessagePayload(message []byte) ([]byte, error) {
 	if len(message) < 2 {
-		return []byte{}, errors.New("Failed to get consensus message payload: no data available.")
+		return []byte{}, errors.New("failed to get consensus message payload: no data available")
 	}
 	return message[MessageTypeBytes:], nil
 }
 
-// Concatenate msgType as one byte with payload, and return the whole byte array
+// ConstructConsensusMessage concatenates msgType as one byte with payload, and return the whole byte array
 func ConstructConsensusMessage(consensusMsgType MessageType, payload []byte) []byte {
 	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Consensus)})
 	byteBuffer.WriteByte(byte(Consensus))
diff --git a/proto/identity/identity.go b/proto/identity/identity.go
index 716dfe165..cafba9cc3 100644
--- a/proto/identity/identity.go
+++ b/proto/identity/identity.go
@@ -10,12 +10,12 @@ import (
 // IdentityMessageTypeBytes is the number of bytes consensus message type occupies
 const IdentityMessageTypeBytes = 1
 
-// IdentityMessageType is the identity message type.
-type IdentityMessageType byte
+// IDMessageType is the identity message type.
+type IDMessageType byte
 
 // Constants of IdentityMessageType.
 const (
-	Identity IdentityMessageType = iota
+	Identity IDMessageType = iota
 	// TODO: add more types
 )
 
@@ -44,7 +44,7 @@ func (msgType MessageType) String() string {
 // GetIdentityMessageType Get the identity message type from the identity message
 func GetIdentityMessageType(message []byte) (MessageType, error) {
 	if len(message) < 1 {
-		return 0, errors.New("Failed to get identity message type: no data available.")
+		return 0, errors.New("failed to get identity message type: no data available")
 	}
 	return MessageType(message[0]), nil
 }
@@ -52,12 +52,12 @@ func GetIdentityMessageType(message []byte) (MessageType, error) {
 // GetIdentityMessagePayload message payload from the identity message
 func GetIdentityMessagePayload(message []byte) ([]byte, error) {
 	if len(message) < 2 {
-		return []byte{}, errors.New("Failed to get identity message payload: no data available.")
+		return []byte{}, errors.New("failed to get identity message payload: no data available")
 	}
 	return message[IdentityMessageTypeBytes:], nil
 }
 
-// Concatenate msgType as one byte with payload, and return the whole byte array
+// ConstructIdentityMessage concatenates msgType as one byte with payload, and return the whole byte array
 func ConstructIdentityMessage(identityMessageType MessageType, payload []byte) []byte {
 	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Identity)})
 	byteBuffer.WriteByte(byte(Identity))
diff --git a/proto/node/node.go b/proto/node/node.go
index 195e93ba1..d440231cd 100644
--- a/proto/node/node.go
+++ b/proto/node/node.go
@@ -28,7 +28,6 @@ const (
 	Block
 	Client
 	Control
-	BlockchainSync
 	PING // node send ip/pki to register with leader
 	PONG // node broadcast pubK
 	// TODO: add more types
@@ -169,25 +168,6 @@ func ConstructTransactionListMessageAccount(transactions types.Transactions) []b
 	return byteBuffer.Bytes()
 }
 
-// ConstructBlockchainSyncMessage constructs Blockchain Sync Message.
-func ConstructBlockchainSyncMessage(msgType BlockchainSyncMessageType, blockHash [32]byte) []byte {
-	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Node)})
-	byteBuffer.WriteByte(byte(BlockchainSync))
-	byteBuffer.WriteByte(byte(msgType))
-	if msgType != GetLastBlockHashes {
-		byteBuffer.Write(blockHash[:])
-	}
-	return byteBuffer.Bytes()
-}
-
-// GenerateBlockchainSyncMessage generates blockchain sync message.
-func GenerateBlockchainSyncMessage(payload []byte) *BlockchainSyncMessage {
-	dec := gob.NewDecoder(bytes.NewBuffer(payload))
-	var res BlockchainSyncMessage
-	dec.Decode(&res)
-	return &res
-}
-
 // ConstructRequestTransactionsMessage constructs serialized transactions
 func ConstructRequestTransactionsMessage(transactionIds [][]byte) []byte {
 	byteBuffer := bytes.NewBuffer([]byte{byte(proto.Node)})
diff --git a/syncing/syncing.go b/syncing/syncing.go
index 14df44604..0c7d3770d 100644
--- a/syncing/syncing.go
+++ b/syncing/syncing.go
@@ -1,7 +1,9 @@
 package syncing
 
 import (
+	"bytes"
 	"reflect"
+	"sort"
 	"sync"
 	"time"
 
@@ -11,6 +13,11 @@ import (
 	"github.com/harmony-one/harmony/syncing/downloader"
 )
 
+// Constants for syncing.
+const (
+	ConsensusRatio = float64(0.66)
+)
+
 // SyncPeerConfig is peer config to sync.
 type SyncPeerConfig struct {
 	ip          string
@@ -27,7 +34,7 @@ type SyncBlockTask struct {
 
 // SyncConfig contains an array of SyncPeerConfig.
 type SyncConfig struct {
-	peers []SyncPeerConfig
+	peers []*SyncPeerConfig
 }
 
 // GetStateSync returns the implementation of StateSyncInterface interface.
@@ -44,6 +51,30 @@ type StateSync struct {
 	stateSyncTaskQueue *queue.Queue
 }
 
+// CreateTestSyncPeerConfig used for testing.
+func CreateTestSyncPeerConfig(client *downloader.Client, blockHashes [][]byte) *SyncPeerConfig {
+	return &SyncPeerConfig{
+		client:      client,
+		blockHashes: blockHashes,
+	}
+}
+
+// CompareSyncPeerConfigByblockHashes compares two SyncPeerConfig by blockHashes.
+func CompareSyncPeerConfigByblockHashes(a *SyncPeerConfig, b *SyncPeerConfig) int {
+	if len(a.blockHashes) != len(b.blockHashes) {
+		if len(a.blockHashes) < len(b.blockHashes) {
+			return -1
+		}
+		return 1
+	}
+	for id := range a.blockHashes {
+		if !reflect.DeepEqual(a.blockHashes[id], b.blockHashes[id]) {
+			return bytes.Compare(a.blockHashes[id], b.blockHashes[id])
+		}
+	}
+	return 0
+}
+
 // GetBlockHashes gets block hashes by calling grpc request to the corresponding peer.
 func (peerConfig *SyncPeerConfig) GetBlockHashes() error {
 	if peerConfig.client == nil {
@@ -82,18 +113,18 @@ func (ss *StateSync) ProcessStateSyncFromPeers(peers []p2p.Peer, bc *blockchain.
 func (ss *StateSync) CreateSyncConfig(peers []p2p.Peer) {
 	ss.peerNumber = len(peers)
 	ss.syncConfig = &SyncConfig{
-		peers: make([]SyncPeerConfig, ss.peerNumber),
+		peers: make([]*SyncPeerConfig, ss.peerNumber),
 	}
 	for id := range ss.syncConfig.peers {
-		ss.syncConfig.peers[id] = SyncPeerConfig{
+		ss.syncConfig.peers[id] = &SyncPeerConfig{
 			ip:   peers[id].IP,
 			port: peers[id].Port,
 		}
 	}
 }
 
-// makeConnectionToPeers makes grpc connection to all peers.
-func (ss *StateSync) makeConnectionToPeers() {
+// MakeConnectionToPeers makes grpc connection to all peers.
+func (ss *StateSync) MakeConnectionToPeers() {
 	var wg sync.WaitGroup
 	wg.Add(ss.peerNumber)
 
@@ -101,9 +132,14 @@ func (ss *StateSync) makeConnectionToPeers() {
 		go func(peerConfig *SyncPeerConfig) {
 			defer wg.Done()
 			peerConfig.client = downloader.ClientSetup(peerConfig.ip, peerConfig.port)
-		}(&ss.syncConfig.peers[id])
+		}(ss.syncConfig.peers[id])
 	}
 	wg.Wait()
+	ss.CleanUpNilPeers()
+}
+
+// CleanUpNilPeers cleans up peer with nil client and recalculate activePeerNumber.
+func (ss *StateSync) CleanUpNilPeers() {
 	ss.activePeerNumber = 0
 	for _, configPeer := range ss.syncConfig.peers {
 		if configPeer.client != nil {
@@ -112,24 +148,70 @@ func (ss *StateSync) makeConnectionToPeers() {
 	}
 }
 
-// areConsensusHashesEqual chesk if all consensus hashes are equal.
-func (ss *StateSync) areConsensusHashesEqual() bool {
-	var firstPeer *SyncPeerConfig
-	for _, configPeer := range ss.syncConfig.peers {
-		if configPeer.client != nil {
-			if firstPeer == nil {
-				firstPeer = &configPeer
-			}
-			if !reflect.DeepEqual(configPeer.blockHashes, firstPeer.blockHashes) {
-				return false
-			}
+// GetHowManyMaxConsensus returns max number of consensus nodes and the first ID of consensus group.
+// Assumption: all peers are sorted by CompareSyncPeerConfigByBlockHashes first.
+func (syncConfig *SyncConfig) GetHowManyMaxConsensus() (int, int) {
+	// As all peers are sorted by their blockHashes, all equal blockHashes should come together and consecutively.
+	curCount := 0
+	curFirstID := -1
+	maxCount := 0
+	maxFirstID := -1
+	for i := range syncConfig.peers {
+		if curFirstID == -1 || CompareSyncPeerConfigByblockHashes(syncConfig.peers[curFirstID], syncConfig.peers[i]) != 0 {
+			curCount = 1
+			curFirstID = i
+		} else {
+			curCount++
+		}
+		if curCount > maxCount {
+			maxCount = curCount
+			maxFirstID = curFirstID
 		}
 	}
-	return true
+	return maxFirstID, maxCount
 }
 
-// getConsensusHashes gets all hashes needed to download.
-func (ss *StateSync) getConsensusHashes() {
+// InitForTesting used for testing.
+func (syncConfig *SyncConfig) InitForTesting(client *downloader.Client, blockHashes [][]byte) {
+	for i := range syncConfig.peers {
+		syncConfig.peers[i].blockHashes = blockHashes
+		syncConfig.peers[i].client = client
+	}
+}
+
+// CleanUpPeers cleans up all peers whose blockHashes are not equal to consensus block hashes.
+func (syncConfig *SyncConfig) CleanUpPeers(maxFirstID int) {
+	fixedPeer := syncConfig.peers[maxFirstID]
+	for i := 0; i < len(syncConfig.peers); i++ {
+		if CompareSyncPeerConfigByblockHashes(fixedPeer, syncConfig.peers[i]) != 0 {
+			// TODO: move it into a util delete func.
+			// See tip https://github.com/golang/go/wiki/SliceTricks
+			// Close the client and remove the peer out of the
+			syncConfig.peers[i].client.Close()
+			copy(syncConfig.peers[i:], syncConfig.peers[i+1:])
+			syncConfig.peers[len(syncConfig.peers)-1] = nil
+			syncConfig.peers = syncConfig.peers[:len(syncConfig.peers)-1]
+		}
+	}
+}
+
+// GetBlockHashesConsensusAndCleanUp chesk if all consensus hashes are equal.
+func (ss *StateSync) GetBlockHashesConsensusAndCleanUp() bool {
+	// Sort all peers by the blockHashes.
+	sort.Slice(ss.syncConfig.peers, func(i, j int) bool {
+		return CompareSyncPeerConfigByblockHashes(ss.syncConfig.peers[i], ss.syncConfig.peers[j]) == -1
+	})
+	maxFirstID, maxCount := ss.syncConfig.GetHowManyMaxConsensus()
+	if float64(maxCount) >= ConsensusRatio*float64(ss.activePeerNumber) {
+		ss.syncConfig.CleanUpPeers(maxFirstID)
+		ss.CleanUpNilPeers()
+		return true
+	}
+	return false
+}
+
+// GetConsensusHashes gets all hashes needed to download.
+func (ss *StateSync) GetConsensusHashes() {
 	for {
 		var wg sync.WaitGroup
 		wg.Add(ss.activePeerNumber)
@@ -142,10 +224,10 @@ func (ss *StateSync) getConsensusHashes() {
 				defer wg.Done()
 				response := peerConfig.client.GetBlockHashes()
 				peerConfig.blockHashes = response.Payload
-			}(&ss.syncConfig.peers[id])
+			}(ss.syncConfig.peers[id])
 		}
 		wg.Wait()
-		if ss.areConsensusHashesEqual() {
+		if ss.GetBlockHashesConsensusAndCleanUp() {
 			break
 		}
 	}
@@ -198,7 +280,7 @@ func (ss *StateSync) downloadBlocks(bc *blockchain.Blockchain) {
 					}
 				}
 			}
-		}(&ss.syncConfig.peers[i], ss.stateSyncTaskQueue, bc)
+		}(ss.syncConfig.peers[i], ss.stateSyncTaskQueue, bc)
 	}
 	wg.Wait()
 }
@@ -208,10 +290,10 @@ func (ss *StateSync) StartStateSync(peers []p2p.Peer, bc *blockchain.Blockchain)
 	// Creates sync config.
 	ss.CreateSyncConfig(peers)
 	// Makes connections to peers.
-	ss.makeConnectionToPeers()
+	ss.MakeConnectionToPeers()
 	for {
 		// Gets consensus hashes.
-		ss.getConsensusHashes()
+		ss.GetConsensusHashes()
 
 		// Generates state-sync task queue.
 		ss.generateStateSyncTaskQueue(bc)
diff --git a/syncing/syncing_test.go b/syncing/syncing_test.go
index 013ac05c0..a55326092 100644
--- a/syncing/syncing_test.go
+++ b/syncing/syncing_test.go
@@ -10,6 +10,7 @@ import (
 	"github.com/harmony-one/harmony/syncing"
 	"github.com/harmony-one/harmony/syncing/downloader"
 	pb "github.com/harmony-one/harmony/syncing/downloader/proto"
+	"github.com/stretchr/testify/assert"
 	"google.golang.org/grpc"
 )
 
@@ -69,6 +70,16 @@ func (node *FakeNode) Init(ip, port string) {
 	node.server = downloader.NewServer(node)
 }
 
+// SetBlockchain is used for testing
+func (node *FakeNode) Init2(ip, port string) {
+	addresses := [][20]byte{TestAddressOne}
+	node.bc = bc.CreateBlockchainWithMoreBlocks(addresses, ShardID)
+	node.ip = ip
+	node.port = port
+
+	node.server = downloader.NewServer(node)
+}
+
 // Start ...
 func (node *FakeNode) Start() error {
 	var err error
@@ -100,6 +111,16 @@ func (node *FakeNode) CalculateResponse(request *pb.DownloaderRequest) (*pb.Down
 	return response, nil
 }
 
+func TestCompareSyncPeerConfigByBlockHashes(t *testing.T) {
+	a := syncing.CreateTestSyncPeerConfig(nil, [][]byte{{1, 2, 3, 4, 5, 6}, {1, 2, 3, 4, 5, 6}})
+	b := syncing.CreateTestSyncPeerConfig(nil, [][]byte{{1, 2, 3, 4, 5, 6}, {1, 2, 3, 4, 5, 6}})
+	assert.Equal(t, syncing.CompareSyncPeerConfigByblockHashes(a, b), 0, "they should be equal")
+	c := syncing.CreateTestSyncPeerConfig(nil, [][]byte{{1, 2, 3, 4, 5, 7}, {1, 2, 3, 4, 5, 6}})
+	assert.Equal(t, syncing.CompareSyncPeerConfigByblockHashes(a, c), -1, "a should be less than c")
+	d := syncing.CreateTestSyncPeerConfig(nil, [][]byte{{1, 2, 3, 4, 5, 4}, {1, 2, 3, 4, 5, 6}})
+	assert.Equal(t, syncing.CompareSyncPeerConfigByblockHashes(a, d), 1, "a should be greater than c")
+}
+
 func TestSyncing(t *testing.T) {
 	fakeNodes := []*FakeNode{&FakeNode{}, &FakeNode{}, &FakeNode{}}
 	for i := range fakeNodes {
@@ -108,6 +129,11 @@ func TestSyncing(t *testing.T) {
 			t.Error(err)
 		}
 	}
+	defer func() {
+		for _, fakeNode := range fakeNodes {
+			fakeNode.grpcServer.Stop()
+		}
+	}()
 
 	stateSync := &syncing.StateSync{}
 	bc := &bc.Blockchain{}
@@ -125,7 +151,41 @@ func TestSyncing(t *testing.T) {
 		}
 	}
 
-	for _, fakeNode := range fakeNodes {
-		fakeNode.grpcServer.Stop()
+}
+
+func TestSyncingIncludingBadNode(t *testing.T) {
+	fakeNodes := []*FakeNode{&FakeNode{}, &FakeNode{}, &FakeNode{}}
+	for i := range fakeNodes {
+		if i == 2 {
+			// Bad node.
+			fakeNodes[i].Init2(serverIP, ServerPorts[i])
+		} else {
+			// Good node.
+			fakeNodes[i].Init(serverIP, ServerPorts[i])
+		}
+		if err := fakeNodes[i].Start(); err != nil {
+			t.Error(err)
+		}
+	}
+	defer func() {
+		for _, fakeNode := range fakeNodes {
+			fakeNode.grpcServer.Stop()
+		}
+	}()
+
+	stateSync := &syncing.StateSync{}
+	bc := &bc.Blockchain{}
+	peers := make([]p2p.Peer, len(fakeNodes))
+	for i := range peers {
+		peers[i].IP = fakeNodes[i].ip
+		peers[i].Port = fakeNodes[i].port
+	}
+
+	stateSync.StartStateSync(peers, bc)
+
+	for i := range bc.Blocks {
+		if !reflect.DeepEqual(bc.Blocks[i], fakeNodes[0].bc.Blocks[i]) {
+			t.Error("not equal")
+		}
 	}
 }
diff --git a/utils/bytes.go b/utils/bytes.go
index a309ad43b..fecc34172 100644
--- a/utils/bytes.go
+++ b/utils/bytes.go
@@ -111,7 +111,7 @@ func LeftPadBytes(slice []byte, l int) []byte {
 	return padded
 }
 
-// Parse the string representation of hex into 32 byte array
+// Get32BytesFromString parses the string representation of hex into 32 byte array
 func Get32BytesFromString(hashString string) ([32]byte, error) {
 	bytes, err := hex.DecodeString(hashString)
 	if err != nil {
diff --git a/utils/distribution_config.go b/utils/distribution_config.go
index ce90fd46b..b4419028b 100644
--- a/utils/distribution_config.go
+++ b/utils/distribution_config.go
@@ -12,6 +12,7 @@ import (
 	"github.com/harmony-one/harmony/p2p"
 )
 
+// ConfigEntry is the config entry.
 type ConfigEntry struct {
 	IP          string
 	Port        string
@@ -20,17 +21,18 @@ type ConfigEntry struct {
 	ValidatorID int // Validator ID in its shard.
 }
 
+// DistributionConfig is the distribution config.
 type DistributionConfig struct {
 	config []ConfigEntry
 }
 
-// done
+// NewDistributionConfig creates new DistributionConfig
 func NewDistributionConfig() *DistributionConfig {
 	config := DistributionConfig{}
 	return &config
 }
 
-// Gets all the leader peers and corresponding shard Ids
+// GetLeadersAndShardIDs gets all the leader peers and corresponding shard Ids
 func (config *DistributionConfig) GetLeadersAndShardIDs() ([]p2p.Peer, []uint32) {
 	var peerList []p2p.Peer
 	var shardIDs []uint32
@@ -48,6 +50,7 @@ func (config *DistributionConfig) GetLeadersAndShardIDs() ([]p2p.Peer, []uint32)
 	return peerList, shardIDs
 }
 
+// GetClientPeer returns client peer.
 func (config *DistributionConfig) GetClientPeer() *p2p.Peer {
 	for _, entry := range config.config {
 		if entry.Role != "client" {
@@ -59,8 +62,7 @@ func (config *DistributionConfig) GetClientPeer() *p2p.Peer {
 	return nil
 }
 
-// done
-// Gets the port of the client node in the config
+// GetClientPort gets the port of the client node in the config
 func (config *DistributionConfig) GetClientPort() string {
 	for _, entry := range config.config {
 		if entry.Role == "client" {
@@ -70,8 +72,7 @@ func (config *DistributionConfig) GetClientPort() string {
 	return ""
 }
 
-// done
-// Parse the config file and return a 2d array containing the file data
+// ReadConfigFile parses the config file and return a 2d array containing the file data
 func (config *DistributionConfig) ReadConfigFile(filename string) error {
 	file, err := os.Open(filename)
 	if err != nil {
@@ -123,7 +124,7 @@ func (config *DistributionConfig) GetPeers(ip, port, shardID string) []p2p.Peer
 	return peerList
 }
 
-// GetPeers Gets the validator list
+// GetSelfPeer Gets the validator list
 func (config *DistributionConfig) GetSelfPeer(ip, port, shardID string) p2p.Peer {
 	for _, entry := range config.config {
 		if entry.IP == ip && entry.Port == port && entry.ShardID == shardID {
@@ -147,10 +148,12 @@ func (config *DistributionConfig) GetLeader(shardID string) p2p.Peer {
 	return leaderPeer
 }
 
+// GetConfigEntries returns a list of ConfigEntry.
 func (config *DistributionConfig) GetConfigEntries() []ConfigEntry {
 	return config.config
 }
 
+// GetMyConfigEntry ...
 func (config *DistributionConfig) GetMyConfigEntry(ip string, port string) *ConfigEntry {
 	if config.config == nil {
 		return nil
@@ -165,6 +168,6 @@ func (config *DistributionConfig) GetMyConfigEntry(ip string, port string) *Conf
 
 func setKey(peer *p2p.Peer) {
 	// Get public key deterministically based on ip and port
-	priKey := crypto.Ed25519Curve.Scalar().SetInt64(int64(GetUniqueIdFromPeer(*peer))) // TODO: figure out why using a random hash value doesn't work for private key (schnorr)
+	priKey := crypto.Ed25519Curve.Scalar().SetInt64(int64(GetUniqueIDFromPeer(*peer))) // TODO: figure out why using a random hash value doesn't work for private key (schnorr)
 	peer.PubKey = pki.GetPublicKeyFromScalar(priKey)
 }
diff --git a/utils/metrics.go b/utils/metrics.go
index adc276f55..0d85470a9 100644
--- a/utils/metrics.go
+++ b/utils/metrics.go
@@ -1,5 +1,6 @@
 package utils
 
+// BToMb ...
 func BToMb(b uint64) uint64 {
 	return b / 1024 / 1024
 }
diff --git a/utils/utils.go b/utils/utils.go
index b91df3a05..5305b130f 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -25,27 +25,23 @@ func ConvertFixedDataIntoByteArray(data interface{}) []byte {
 }
 
 // TODO(minhdoan): this is probably a hack, probably needs some strong non-collision hash.
-func GetUniqueIdFromPeer(peer p2p.Peer) uint16 {
-	reg, err := regexp.Compile("[^0-9]+")
-	if err != nil {
-		log.Panic("Regex Compilation Failed", "err", err)
-	}
-	socketId := reg.ReplaceAllString(peer.IP+peer.Port, "") // A integer Id formed by unique IP/PORT pair
-	value, _ := strconv.Atoi(socketId)
-	return uint16(value)
+// GetUniqueIDFromPeer --
+func GetUniqueIDFromPeer(peer p2p.Peer) uint16 {
+	return GetUniqueIDFromIPPort(peer.IP, peer.Port)
 }
 
-func GetUniqueIdFromIPPort(ip, port string) uint16 {
+// GetUniqueIDFromIPPort --
+func GetUniqueIDFromIPPort(ip, port string) uint16 {
 	reg, err := regexp.Compile("[^0-9]+")
 	if err != nil {
 		log.Panic("Regex Compilation Failed", "err", err)
 	}
-	socketId := reg.ReplaceAllString(ip+port, "") // A integer Id formed by unique IP/PORT pair
-	value, _ := strconv.Atoi(socketId)
+	socketID := reg.ReplaceAllString(ip+port, "") // A integer Id formed by unique IP/PORT pair
+	value, _ := strconv.Atoi(socketID)
 	return uint16(value)
 }
 
-// RunCmd Runs command `name` with arguments `args`
+// RunCmd runs command `name` with arguments `args`
 func RunCmd(name string, args ...string) error {
 	cmd := exec.Command(name, args...)
 	if err := cmd.Start(); err != nil {
@@ -64,8 +60,9 @@ func RunCmd(name string, args ...string) error {
 	return nil
 }
 
+// GenKey generates a key given ip and port.
 func GenKey(ip, port string) (kyber.Scalar, kyber.Point) {
-	priKey := crypto.Ed25519Curve.Scalar().SetInt64(int64(GetUniqueIdFromIPPort(ip, port))) // TODO: figure out why using a random hash value doesn't work for private key (schnorr)
+	priKey := crypto.Ed25519Curve.Scalar().SetInt64(int64(GetUniqueIDFromIPPort(ip, port))) // TODO: figure out why using a random hash value doesn't work for private key (schnorr)
 	pubKey := pki.GetPublicKeyFromScalar(priKey)
 
 	return priKey, pubKey