diff --git a/src/AntShares/Consensus/ConsensusService.cs b/src/AntShares/Consensus/ConsensusService.cs
index 592b66dd3f..268f0887fa 100644
--- a/src/AntShares/Consensus/ConsensusService.cs
+++ b/src/AntShares/Consensus/ConsensusService.cs
@@ -1,363 +1,374 @@
-using AntShares.Core;
-using AntShares.IO;
-using AntShares.Network;
-using AntShares.Network.Payloads;
-using AntShares.Wallets;
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Threading;
-
-namespace AntShares.Consensus
-{
-    public class ConsensusService : IDisposable
-    {
-        private ConsensusContext context = new ConsensusContext();
-        private LocalNode localNode;
-        private Wallet wallet;
-        private Timer timer;
-        private uint timer_height;
-        private byte timer_view;
-        private DateTime block_received_time;
-        private string log_dictionary;
-        private bool started = false;
-
-        public ConsensusService(LocalNode localNode, Wallet wallet, string log_dictionary = null)
-        {
-            this.localNode = localNode;
-            this.wallet = wallet;
-            this.timer = new Timer(OnTimeout, null, Timeout.Infinite, Timeout.Infinite);
-            this.log_dictionary = log_dictionary;
-        }
-
-        private bool AddTransaction(Transaction tx, bool verify)
-        {
-            if (Blockchain.Default.ContainsTransaction(tx.Hash) ||
-                (verify && !tx.Verify(context.Transactions.Values)) ||
-                !CheckPolicy(tx))
-            {
-                Log($"reject tx: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}");
-                RequestChangeView();
-                return false;
-            }
-            context.Transactions[tx.Hash] = tx;
-            if (context.TransactionHashes.Length == context.Transactions.Count)
-            {
-                if (Blockchain.GetMinerAddress(Blockchain.Default.GetMiners(context.Transactions.Values).ToArray()).Equals(context.NextMiner))
-                {
-                    Log($"send perpare response");
-                    context.State |= ConsensusState.SignatureSent;
-                    context.Signatures[context.MinerIndex] = context.MakeHeader().Sign(wallet.GetAccount(context.Miners[context.MinerIndex]));
-                    SignAndRelay(context.MakePerpareResponse(context.Signatures[context.MinerIndex]));
-                    CheckSignatures();
-                }
-                else
-                {
-                    RequestChangeView();
-                    return false;
-                }
-            }
-            return true;
-        }
-
-        private void Blockchain_PersistCompleted(object sender, Block block)
-        {
-            Log($"persist block: {block.Hash}");
-            block_received_time = DateTime.Now;
-            InitializeConsensus(0);
-        }
-
-        private void CheckExpectedView(byte view_number)
-        {
-            if (context.ViewNumber == view_number) return;
-            if (context.ExpectedView.Count(p => p == view_number) >= context.M)
-            {
-                InitializeConsensus(view_number);
-            }
-        }
-
-        private static bool CheckPolicy(Transaction tx)
-        {
-            switch (Policy.Default.PolicyLevel)
-            {
-                case PolicyLevel.AllowAll:
-                    return true;
-                case PolicyLevel.AllowList:
-                    return tx.Scripts.All(p => Policy.Default.List.Contains(p.RedeemScript.ToScriptHash())) || tx.Outputs.All(p => Policy.Default.List.Contains(p.ScriptHash));
-                case PolicyLevel.DenyList:
-                    return tx.Scripts.All(p => !Policy.Default.List.Contains(p.RedeemScript.ToScriptHash())) && tx.Outputs.All(p => !Policy.Default.List.Contains(p.ScriptHash));
-                default:
-                    return false;
-            }
-        }
-
-        private void CheckSignatures()
-        {
-            if (context.Signatures.Count(p => p != null) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
-            {
-                Contract contract = Contract.CreateMultiSigContract(context.Miners[context.MinerIndex].EncodePoint(true).ToScriptHash(), context.M, context.Miners);
-                Block block = context.MakeHeader();
-                SignatureContext sc = new SignatureContext(block);
-                for (int i = 0, j = 0; i < context.Miners.Length && j < context.M; i++)
-                    if (context.Signatures[i] != null)
-                    {
-                        sc.AddSignature(contract, context.Miners[i], context.Signatures[i]);
-                        j++;
-                    }
-                sc.Signable.Scripts = sc.GetScripts();
-                block.Transactions = context.TransactionHashes.Select(p => context.Transactions[p]).ToArray();
-                Log($"relay block: {block.Hash}");
-                if (!localNode.Relay(block))
-                    Log($"reject block: {block.Hash}");
-                context.State |= ConsensusState.BlockSent;
-            }
-        }
-
-        private MinerTransaction CreateMinerTransaction(IEnumerable<Transaction> transactions, uint height, ulong nonce)
-        {
-            Fixed8 amount_netfee = Block.CalculateNetFee(transactions);
-            TransactionOutput[] outputs = amount_netfee == Fixed8.Zero ? new TransactionOutput[0] : new[] { new TransactionOutput
-            {
-                AssetId = Blockchain.AntCoin.Hash,
-                Value = amount_netfee,
-                ScriptHash = wallet.GetContracts().First().ScriptHash
-            } };
-            return new MinerTransaction
-            {
-                Nonce = (uint)(nonce % (uint.MaxValue + 1ul)),
-                Attributes = new TransactionAttribute[0],
-                Inputs = new CoinReference[0],
-                Outputs = outputs,
-                Scripts = new Witness[0]
-            };
-        }
-
-        public void Dispose()
-        {
-            Log("OnStop");
-            if (timer != null) timer.Dispose();
-            if (started)
-            {
-                Blockchain.PersistCompleted -= Blockchain_PersistCompleted;
-                LocalNode.NewInventory -= LocalNode_NewInventory;
-            }
-        }
-
-        private static ulong GetNonce()
-        {
-            byte[] nonce = new byte[sizeof(ulong)];
-            Random rand = new Random();
-            rand.NextBytes(nonce);
-            return nonce.ToUInt64(0);
-        }
-
-        private void InitializeConsensus(byte view_number)
-        {
-            lock (context)
-            {
-                if (view_number == 0)
-                    context.Reset(wallet);
-                else
-                    context.ChangeView(view_number);
-                if (context.MinerIndex < 0) return;
-                Log($"initialize: height={context.Height} view={view_number} index={context.MinerIndex} role={(context.MinerIndex == context.PrimaryIndex ? ConsensusState.Primary : ConsensusState.Backup)}");
-                if (context.MinerIndex == context.PrimaryIndex)
-                {
-                    context.State |= ConsensusState.Primary;
-                    timer_height = context.Height;
-                    timer_view = view_number;
-                    TimeSpan span = DateTime.Now - block_received_time;
-                    if (span >= Blockchain.TimePerBlock)
-                        timer.Change(0, Timeout.Infinite);
-                    else
-                        timer.Change(Blockchain.TimePerBlock - span, Timeout.InfiniteTimeSpan);
-                }
-                else
-                {
-                    context.State = ConsensusState.Backup;
-                    timer_height = context.Height;
-                    timer_view = view_number;
-                    timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (view_number + 1)), Timeout.InfiniteTimeSpan);
-                }
-            }
-        }
-
-        private void LocalNode_NewInventory(object sender, IInventory inventory)
-        {
-            ConsensusPayload payload = inventory as ConsensusPayload;
-            if (payload != null)
-            {
-                lock (context)
-                {
-                    if (payload.MinerIndex == context.MinerIndex) return;
-                    if (payload.Version != ConsensusContext.Version || payload.PrevHash != context.PrevHash || payload.Height != context.Height)
-                        return;
-                    if (payload.MinerIndex >= context.Miners.Length) return;
-                    ConsensusMessage message = ConsensusMessage.DeserializeFrom(payload.Data);
-                    if (message.ViewNumber != context.ViewNumber && message.Type != ConsensusMessageType.ChangeView)
-                        return;
-                    switch (message.Type)
-                    {
-                        case ConsensusMessageType.ChangeView:
-                            OnChangeViewReceived(payload, (ChangeView)message);
-                            break;
-                        case ConsensusMessageType.PerpareRequest:
-                            OnPerpareRequestReceived(payload, (PerpareRequest)message);
-                            break;
-                        case ConsensusMessageType.PerpareResponse:
-                            OnPerpareResponseReceived(payload, (PerpareResponse)message);
-                            break;
-                    }
-                }
-            }
-            Transaction tx = inventory as Transaction;
-            if (tx != null)
-            {
-                lock (context)
-                {
-                    if (!context.State.HasFlag(ConsensusState.Backup) || !context.State.HasFlag(ConsensusState.RequestReceived) || context.State.HasFlag(ConsensusState.SignatureSent))
-                        return;
-                    if (context.Transactions.ContainsKey(tx.Hash)) return;
-                    if (!context.TransactionHashes.Contains(tx.Hash)) return;
-                    AddTransaction(tx, true);
-                }
-            }
-        }
-
-        private void Log(string message)
-        {
-            DateTime now = DateTime.Now;
-            string line = $"[{now.TimeOfDay:hh\\:mm\\:ss}] {message}";
-            Console.WriteLine(line);
-            if (string.IsNullOrEmpty(log_dictionary)) return;
-            lock (log_dictionary)
-            {
-                Directory.CreateDirectory(log_dictionary);
-                string path = Path.Combine(log_dictionary, $"{now:yyyy-MM-dd}.log");
-                File.AppendAllLines(path, new[] { line });
-            }
-        }
-
-        private void OnChangeViewReceived(ConsensusPayload payload, ChangeView message)
-        {
-            Log($"{nameof(OnChangeViewReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex} nv={message.NewViewNumber}");
-            if (message.NewViewNumber <= context.ExpectedView[payload.MinerIndex])
-                return;
-            context.ExpectedView[payload.MinerIndex] = message.NewViewNumber;
-            CheckExpectedView(message.NewViewNumber);
-        }
-
-        private void OnPerpareRequestReceived(ConsensusPayload payload, PerpareRequest message)
-        {
-            Log($"{nameof(OnPerpareRequestReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex} tx={message.TransactionHashes.Length}");
-            if (!context.State.HasFlag(ConsensusState.Backup) || context.State.HasFlag(ConsensusState.RequestReceived))
-                return;
-            if (payload.MinerIndex != context.PrimaryIndex) return;
-            if (payload.Timestamp <= Blockchain.Default.GetHeader(context.PrevHash).Timestamp || payload.Timestamp > DateTime.Now.AddMinutes(10).ToTimestamp())
-            {
-                Log($"Timestamp incorrect: {payload.Timestamp}");
-                return;
-            }
-            context.State |= ConsensusState.RequestReceived;
-            context.Timestamp = payload.Timestamp;
-            context.Nonce = message.Nonce;
-            context.NextMiner = message.NextMiner;
-            context.TransactionHashes = message.TransactionHashes;
-            context.Transactions = new Dictionary<UInt256, Transaction>();
-            if (!context.MakeHeader().VerifySignature(context.Miners[payload.MinerIndex], message.Signature)) return;
-            context.Signatures = new byte[context.Miners.Length][];
-            context.Signatures[payload.MinerIndex] = message.Signature;
-            Dictionary<UInt256, Transaction> mempool = LocalNode.GetMemoryPool().ToDictionary(p => p.Hash);
-            foreach (UInt256 hash in context.TransactionHashes.Skip(1))
-                if (mempool.ContainsKey(hash))
-                    if (!AddTransaction(mempool[hash], false))
-                        return;
-            if (!AddTransaction(message.MinerTransaction, true)) return;
-            LocalNode.AllowHashes(context.TransactionHashes.Except(context.Transactions.Keys));
-            if (context.Transactions.Count < context.TransactionHashes.Length)
-                localNode.SynchronizeMemoryPool();
-        }
-
-        private void OnPerpareResponseReceived(ConsensusPayload payload, PerpareResponse message)
-        {
-            Log($"{nameof(OnPerpareResponseReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex}");
-            if (context.State.HasFlag(ConsensusState.BlockSent)) return;
-            if (context.Signatures[payload.MinerIndex] != null) return;
-            Block header = context.MakeHeader();
-            if (header == null || !header.VerifySignature(context.Miners[payload.MinerIndex], message.Signature)) return;
-            context.Signatures[payload.MinerIndex] = message.Signature;
-            CheckSignatures();
-        }
-
-        private void OnTimeout(object state)
-        {
-            lock (context)
-            {
-                if (timer_height != context.Height || timer_view != context.ViewNumber) return;
-                Log($"timeout: height={timer_height} view={timer_view} state={context.State}");
-                if (context.State.HasFlag(ConsensusState.Primary) && !context.State.HasFlag(ConsensusState.RequestSent))
-                {
-                    Log($"send perpare request: height={timer_height} view={timer_view}");
-                    context.State |= ConsensusState.RequestSent;
-                    if (!context.State.HasFlag(ConsensusState.SignatureSent))
-                    {
-                        context.Timestamp = Math.Max(DateTime.Now.ToTimestamp(), Blockchain.Default.GetHeader(context.PrevHash).Timestamp + 1);
-                        context.Nonce = GetNonce();
-                        List<Transaction> transactions = LocalNode.GetMemoryPool().Where(p => CheckPolicy(p)).ToList();
-                        transactions.Insert(0, CreateMinerTransaction(transactions, context.Height, context.Nonce));
-                        context.TransactionHashes = transactions.Select(p => p.Hash).ToArray();
-                        context.Transactions = transactions.ToDictionary(p => p.Hash);
-                        context.NextMiner = Blockchain.GetMinerAddress(Blockchain.Default.GetMiners(transactions).ToArray());
-                        context.Signatures[context.MinerIndex] = context.MakeHeader().Sign(wallet.GetAccount(context.Miners[context.MinerIndex]));
-                    }
-                    SignAndRelay(context.MakePerpareRequest());
-                    timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (timer_view + 1)), Timeout.InfiniteTimeSpan);
-                }
-                else if ((context.State.HasFlag(ConsensusState.Primary) && context.State.HasFlag(ConsensusState.RequestSent)) || context.State.HasFlag(ConsensusState.Backup))
-                {
-                    RequestChangeView();
-                }
-            }
-        }
-
-        public void RefreshPolicy()
-        {
-            Policy.Default.Refresh();
-        }
-
-        private void RequestChangeView()
-        {
-            context.ExpectedView[context.MinerIndex]++;
-            Log($"request change view: height={context.Height} view={context.ViewNumber} nv={context.ExpectedView[context.MinerIndex]} state={context.State}");
-            timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (context.ExpectedView[context.MinerIndex] + 1)), Timeout.InfiniteTimeSpan);
-            SignAndRelay(context.MakeChangeView());
-            CheckExpectedView(context.ExpectedView[context.MinerIndex]);
-        }
-
-        private void SignAndRelay(ConsensusPayload payload)
-        {
-            SignatureContext sc;
-            try
-            {
-                sc = new SignatureContext(payload);
-            }
-            catch (InvalidOperationException)
-            {
-                return;
-            }
-            wallet.Sign(sc);
-            sc.Signable.Scripts = sc.GetScripts();
-            localNode.RelayDirectly(payload);
-        }
-
-        public void Start()
-        {
-            Log("OnStart");
-            started = true;
-            Blockchain.PersistCompleted += Blockchain_PersistCompleted;
-            LocalNode.NewInventory += LocalNode_NewInventory;
-            InitializeConsensus(0);
-        }
-    }
-}
+using AntShares.Core;
+using AntShares.IO;
+using AntShares.Network;
+using AntShares.Network.Payloads;
+using AntShares.Wallets;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading;
+
+namespace AntShares.Consensus
+{
+    public class ConsensusService : IDisposable
+    {
+        public const int MaxTransactionsPerBlock = 15000;
+
+        private ConsensusContext context = new ConsensusContext();
+        private LocalNode localNode;
+        private Wallet wallet;
+        private Timer timer;
+        private uint timer_height;
+        private byte timer_view;
+        private DateTime block_received_time;
+        private string log_dictionary;
+        private bool started = false;
+
+        public ConsensusService(LocalNode localNode, Wallet wallet, string log_dictionary = null)
+        {
+            this.localNode = localNode;
+            this.wallet = wallet;
+            this.timer = new Timer(OnTimeout, null, Timeout.Infinite, Timeout.Infinite);
+            this.log_dictionary = log_dictionary;
+        }
+
+        private bool AddTransaction(Transaction tx, bool verify)
+        {
+            if (Blockchain.Default.ContainsTransaction(tx.Hash) ||
+                (verify && !tx.Verify(context.Transactions.Values)) ||
+                !CheckPolicy(tx))
+            {
+                Log($"reject tx: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}");
+                RequestChangeView();
+                return false;
+            }
+            context.Transactions[tx.Hash] = tx;
+            if (context.TransactionHashes.Length == context.Transactions.Count)
+            {
+                if (Blockchain.GetMinerAddress(Blockchain.Default.GetMiners(context.Transactions.Values).ToArray()).Equals(context.NextMiner))
+                {
+                    Log($"send perpare response");
+                    context.State |= ConsensusState.SignatureSent;
+                    context.Signatures[context.MinerIndex] = context.MakeHeader().Sign(wallet.GetAccount(context.Miners[context.MinerIndex]));
+                    SignAndRelay(context.MakePerpareResponse(context.Signatures[context.MinerIndex]));
+                    CheckSignatures();
+                }
+                else
+                {
+                    RequestChangeView();
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        private void Blockchain_PersistCompleted(object sender, Block block)
+        {
+            Log($"persist block: {block.Hash}");
+            block_received_time = DateTime.Now;
+            InitializeConsensus(0);
+        }
+
+        private void CheckExpectedView(byte view_number)
+        {
+            if (context.ViewNumber == view_number) return;
+            if (context.ExpectedView.Count(p => p == view_number) >= context.M)
+            {
+                InitializeConsensus(view_number);
+            }
+        }
+
+        private static bool CheckPolicy(Transaction tx)
+        {
+            switch (Policy.Default.PolicyLevel)
+            {
+                case PolicyLevel.AllowAll:
+                    return true;
+                case PolicyLevel.AllowList:
+                    return tx.Scripts.All(p => Policy.Default.List.Contains(p.RedeemScript.ToScriptHash())) || tx.Outputs.All(p => Policy.Default.List.Contains(p.ScriptHash));
+                case PolicyLevel.DenyList:
+                    return tx.Scripts.All(p => !Policy.Default.List.Contains(p.RedeemScript.ToScriptHash())) && tx.Outputs.All(p => !Policy.Default.List.Contains(p.ScriptHash));
+                default:
+                    return false;
+            }
+        }
+
+        private void CheckSignatures()
+        {
+            if (context.Signatures.Count(p => p != null) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
+            {
+                Contract contract = Contract.CreateMultiSigContract(context.Miners[context.MinerIndex].EncodePoint(true).ToScriptHash(), context.M, context.Miners);
+                Block block = context.MakeHeader();
+                SignatureContext sc = new SignatureContext(block);
+                for (int i = 0, j = 0; i < context.Miners.Length && j < context.M; i++)
+                    if (context.Signatures[i] != null)
+                    {
+                        sc.AddSignature(contract, context.Miners[i], context.Signatures[i]);
+                        j++;
+                    }
+                sc.Signable.Scripts = sc.GetScripts();
+                block.Transactions = context.TransactionHashes.Select(p => context.Transactions[p]).ToArray();
+                Log($"relay block: {block.Hash}");
+                if (!localNode.Relay(block))
+                    Log($"reject block: {block.Hash}");
+                context.State |= ConsensusState.BlockSent;
+            }
+        }
+
+        private MinerTransaction CreateMinerTransaction(IEnumerable<Transaction> transactions, uint height, ulong nonce)
+        {
+            Fixed8 amount_netfee = Block.CalculateNetFee(transactions);
+            TransactionOutput[] outputs = amount_netfee == Fixed8.Zero ? new TransactionOutput[0] : new[] { new TransactionOutput
+            {
+                AssetId = Blockchain.AntCoin.Hash,
+                Value = amount_netfee,
+                ScriptHash = wallet.GetContracts().First().ScriptHash
+            } };
+            return new MinerTransaction
+            {
+                Nonce = (uint)(nonce % (uint.MaxValue + 1ul)),
+                Attributes = new TransactionAttribute[0],
+                Inputs = new CoinReference[0],
+                Outputs = outputs,
+                Scripts = new Witness[0]
+            };
+        }
+
+        public void Dispose()
+        {
+            Log("OnStop");
+            if (timer != null) timer.Dispose();
+            if (started)
+            {
+                Blockchain.PersistCompleted -= Blockchain_PersistCompleted;
+                LocalNode.InventoryReceiving -= LocalNode_InventoryReceiving;
+                LocalNode.InventoryReceived -= LocalNode_InventoryReceived;
+            }
+        }
+
+        private static ulong GetNonce()
+        {
+            byte[] nonce = new byte[sizeof(ulong)];
+            Random rand = new Random();
+            rand.NextBytes(nonce);
+            return nonce.ToUInt64(0);
+        }
+
+        private void InitializeConsensus(byte view_number)
+        {
+            lock (context)
+            {
+                if (view_number == 0)
+                    context.Reset(wallet);
+                else
+                    context.ChangeView(view_number);
+                if (context.MinerIndex < 0) return;
+                Log($"initialize: height={context.Height} view={view_number} index={context.MinerIndex} role={(context.MinerIndex == context.PrimaryIndex ? ConsensusState.Primary : ConsensusState.Backup)}");
+                if (context.MinerIndex == context.PrimaryIndex)
+                {
+                    context.State |= ConsensusState.Primary;
+                    timer_height = context.Height;
+                    timer_view = view_number;
+                    TimeSpan span = DateTime.Now - block_received_time;
+                    if (span >= Blockchain.TimePerBlock)
+                        timer.Change(0, Timeout.Infinite);
+                    else
+                        timer.Change(Blockchain.TimePerBlock - span, Timeout.InfiniteTimeSpan);
+                }
+                else
+                {
+                    context.State = ConsensusState.Backup;
+                    timer_height = context.Height;
+                    timer_view = view_number;
+                    timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (view_number + 1)), Timeout.InfiniteTimeSpan);
+                }
+            }
+        }
+
+        private void LocalNode_InventoryReceived(object sender, IInventory inventory)
+        {
+            ConsensusPayload payload = inventory as ConsensusPayload;
+            if (payload != null)
+            {
+                lock (context)
+                {
+                    if (payload.MinerIndex == context.MinerIndex) return;
+                    if (payload.Version != ConsensusContext.Version || payload.PrevHash != context.PrevHash || payload.Height != context.Height)
+                        return;
+                    if (payload.MinerIndex >= context.Miners.Length) return;
+                    ConsensusMessage message = ConsensusMessage.DeserializeFrom(payload.Data);
+                    if (message.ViewNumber != context.ViewNumber && message.Type != ConsensusMessageType.ChangeView)
+                        return;
+                    switch (message.Type)
+                    {
+                        case ConsensusMessageType.ChangeView:
+                            OnChangeViewReceived(payload, (ChangeView)message);
+                            break;
+                        case ConsensusMessageType.PerpareRequest:
+                            OnPerpareRequestReceived(payload, (PerpareRequest)message);
+                            break;
+                        case ConsensusMessageType.PerpareResponse:
+                            OnPerpareResponseReceived(payload, (PerpareResponse)message);
+                            break;
+                    }
+                }
+            }
+        }
+
+        private void LocalNode_InventoryReceiving(object sender, InventoryReceivingEventArgs e)
+        {
+            Transaction tx = e.Inventory as Transaction;
+            if (tx != null)
+            {
+                lock (context)
+                {
+                    if (!context.State.HasFlag(ConsensusState.Backup) || !context.State.HasFlag(ConsensusState.RequestReceived) || context.State.HasFlag(ConsensusState.SignatureSent))
+                        return;
+                    if (context.Transactions.ContainsKey(tx.Hash)) return;
+                    if (!context.TransactionHashes.Contains(tx.Hash)) return;
+                    AddTransaction(tx, true);
+                    e.Cancel = true;
+                }
+            }
+        }
+
+        private void Log(string message)
+        {
+            DateTime now = DateTime.Now;
+            string line = $"[{now.TimeOfDay:hh\\:mm\\:ss}] {message}";
+            Console.WriteLine(line);
+            if (string.IsNullOrEmpty(log_dictionary)) return;
+            lock (log_dictionary)
+            {
+                Directory.CreateDirectory(log_dictionary);
+                string path = Path.Combine(log_dictionary, $"{now:yyyy-MM-dd}.log");
+                File.AppendAllLines(path, new[] { line });
+            }
+        }
+
+        private void OnChangeViewReceived(ConsensusPayload payload, ChangeView message)
+        {
+            Log($"{nameof(OnChangeViewReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex} nv={message.NewViewNumber}");
+            if (message.NewViewNumber <= context.ExpectedView[payload.MinerIndex])
+                return;
+            context.ExpectedView[payload.MinerIndex] = message.NewViewNumber;
+            CheckExpectedView(message.NewViewNumber);
+        }
+
+        private void OnPerpareRequestReceived(ConsensusPayload payload, PerpareRequest message)
+        {
+            Log($"{nameof(OnPerpareRequestReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex} tx={message.TransactionHashes.Length}");
+            if (!context.State.HasFlag(ConsensusState.Backup) || context.State.HasFlag(ConsensusState.RequestReceived))
+                return;
+            if (payload.MinerIndex != context.PrimaryIndex) return;
+            if (payload.Timestamp <= Blockchain.Default.GetHeader(context.PrevHash).Timestamp || payload.Timestamp > DateTime.Now.AddMinutes(10).ToTimestamp())
+            {
+                Log($"Timestamp incorrect: {payload.Timestamp}");
+                return;
+            }
+            context.State |= ConsensusState.RequestReceived;
+            context.Timestamp = payload.Timestamp;
+            context.Nonce = message.Nonce;
+            context.NextMiner = message.NextMiner;
+            context.TransactionHashes = message.TransactionHashes;
+            context.Transactions = new Dictionary<UInt256, Transaction>();
+            if (!context.MakeHeader().VerifySignature(context.Miners[payload.MinerIndex], message.Signature)) return;
+            context.Signatures = new byte[context.Miners.Length][];
+            context.Signatures[payload.MinerIndex] = message.Signature;
+            Dictionary<UInt256, Transaction> mempool = LocalNode.GetMemoryPool().ToDictionary(p => p.Hash);
+            foreach (UInt256 hash in context.TransactionHashes.Skip(1))
+                if (mempool.ContainsKey(hash))
+                    if (!AddTransaction(mempool[hash], false))
+                        return;
+            if (!AddTransaction(message.MinerTransaction, true)) return;
+            LocalNode.AllowHashes(context.TransactionHashes.Except(context.Transactions.Keys));
+            if (context.Transactions.Count < context.TransactionHashes.Length)
+                localNode.SynchronizeMemoryPool();
+        }
+
+        private void OnPerpareResponseReceived(ConsensusPayload payload, PerpareResponse message)
+        {
+            Log($"{nameof(OnPerpareResponseReceived)}: height={payload.Height} view={message.ViewNumber} index={payload.MinerIndex}");
+            if (context.State.HasFlag(ConsensusState.BlockSent)) return;
+            if (context.Signatures[payload.MinerIndex] != null) return;
+            Block header = context.MakeHeader();
+            if (header == null || !header.VerifySignature(context.Miners[payload.MinerIndex], message.Signature)) return;
+            context.Signatures[payload.MinerIndex] = message.Signature;
+            CheckSignatures();
+        }
+
+        private void OnTimeout(object state)
+        {
+            lock (context)
+            {
+                if (timer_height != context.Height || timer_view != context.ViewNumber) return;
+                Log($"timeout: height={timer_height} view={timer_view} state={context.State}");
+                if (context.State.HasFlag(ConsensusState.Primary) && !context.State.HasFlag(ConsensusState.RequestSent))
+                {
+                    Log($"send perpare request: height={timer_height} view={timer_view}");
+                    context.State |= ConsensusState.RequestSent;
+                    if (!context.State.HasFlag(ConsensusState.SignatureSent))
+                    {
+                        context.Timestamp = Math.Max(DateTime.Now.ToTimestamp(), Blockchain.Default.GetHeader(context.PrevHash).Timestamp + 1);
+                        context.Nonce = GetNonce();
+                        List<Transaction> transactions = LocalNode.GetMemoryPool().Where(p => CheckPolicy(p)).ToList();
+                        if (transactions.Count >= MaxTransactionsPerBlock)
+                            transactions = transactions.OrderByDescending(p => p.NetworkFee / p.Size).Take(MaxTransactionsPerBlock - 1).ToList();
+                        transactions.Insert(0, CreateMinerTransaction(transactions, context.Height, context.Nonce));
+                        context.TransactionHashes = transactions.Select(p => p.Hash).ToArray();
+                        context.Transactions = transactions.ToDictionary(p => p.Hash);
+                        context.NextMiner = Blockchain.GetMinerAddress(Blockchain.Default.GetMiners(transactions).ToArray());
+                        context.Signatures[context.MinerIndex] = context.MakeHeader().Sign(wallet.GetAccount(context.Miners[context.MinerIndex]));
+                    }
+                    SignAndRelay(context.MakePerpareRequest());
+                    timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (timer_view + 1)), Timeout.InfiniteTimeSpan);
+                }
+                else if ((context.State.HasFlag(ConsensusState.Primary) && context.State.HasFlag(ConsensusState.RequestSent)) || context.State.HasFlag(ConsensusState.Backup))
+                {
+                    RequestChangeView();
+                }
+            }
+        }
+
+        public void RefreshPolicy()
+        {
+            Policy.Default.Refresh();
+        }
+
+        private void RequestChangeView()
+        {
+            context.ExpectedView[context.MinerIndex]++;
+            Log($"request change view: height={context.Height} view={context.ViewNumber} nv={context.ExpectedView[context.MinerIndex]} state={context.State}");
+            timer.Change(TimeSpan.FromSeconds(Blockchain.SecondsPerBlock << (context.ExpectedView[context.MinerIndex] + 1)), Timeout.InfiniteTimeSpan);
+            SignAndRelay(context.MakeChangeView());
+            CheckExpectedView(context.ExpectedView[context.MinerIndex]);
+        }
+
+        private void SignAndRelay(ConsensusPayload payload)
+        {
+            SignatureContext sc;
+            try
+            {
+                sc = new SignatureContext(payload);
+            }
+            catch (InvalidOperationException)
+            {
+                return;
+            }
+            wallet.Sign(sc);
+            sc.Signable.Scripts = sc.GetScripts();
+            localNode.RelayDirectly(payload);
+        }
+
+        public void Start()
+        {
+            Log("OnStart");
+            started = true;
+            Blockchain.PersistCompleted += Blockchain_PersistCompleted;
+            LocalNode.InventoryReceiving += LocalNode_InventoryReceiving;
+            LocalNode.InventoryReceived += LocalNode_InventoryReceived;
+            InitializeConsensus(0);
+        }
+    }
+}
diff --git a/src/AntShares/Core/Transaction.cs b/src/AntShares/Core/Transaction.cs
index b8c2f2c8ca..e8694e95ff 100644
--- a/src/AntShares/Core/Transaction.cs
+++ b/src/AntShares/Core/Transaction.cs
@@ -1,388 +1,405 @@
-using AntShares.Cryptography;
-using AntShares.Cryptography.ECC;
-using AntShares.IO;
-using AntShares.IO.Json;
-using AntShares.Network;
-using AntShares.VM;
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Reflection;
-using System.Text;
-
-namespace AntShares.Core
-{
-    /// <summary>
-    /// 一切交易的基类
-    /// </summary>
-    public abstract class Transaction : IEquatable<Transaction>, IInventory
-    {
-        /// <summary>
-        /// 交易类型
-        /// </summary>
-        public readonly TransactionType Type;
-        /// <summary>
-        /// 版本
-        /// </summary>
-        public byte Version;
-        /// <summary>
-        /// 该交易所具备的额外特性
-        /// </summary>
-        public TransactionAttribute[] Attributes;
-        /// <summary>
-        /// 输入列表
-        /// </summary>
-        public CoinReference[] Inputs;
-        /// <summary>
-        /// 输出列表
-        /// </summary>
-        public TransactionOutput[] Outputs;
-        /// <summary>
-        /// 用于验证该交易的脚本列表
-        /// </summary>
-        public Witness[] Scripts { get; set; }
-
-        private UInt256 _hash = null;
-        public UInt256 Hash
-        {
-            get
-            {
-                if (_hash == null)
-                {
-                    _hash = new UInt256(this.GetHashData().Sha256().Sha256());
-                }
-                return _hash;
-            }
-        }
-
-        /// <summary>
-        /// 清单类型
-        /// </summary>
-        InventoryType IInventory.InventoryType => InventoryType.TX;
-
-        private IReadOnlyDictionary<CoinReference, TransactionOutput> _references;
-        /// <summary>
-        /// 每一个交易输入所引用的交易输出
-        /// </summary>
-        public IReadOnlyDictionary<CoinReference, TransactionOutput> References
-        {
-            get
-            {
-                if (_references == null)
-                {
-                    Dictionary<CoinReference, TransactionOutput> dictionary = new Dictionary<CoinReference, TransactionOutput>();
-                    foreach (var group in Inputs.GroupBy(p => p.PrevHash))
-                    {
-                        Transaction tx = Blockchain.Default.GetTransaction(group.Key);
-                        if (tx == null) return null;
-                        foreach (var reference in group.Select(p => new
-                        {
-                            Input = p,
-                            Output = tx.Outputs[p.PrevIndex]
-                        }))
-                        {
-                            dictionary.Add(reference.Input, reference.Output);
-                        }
-                    }
-                    _references = dictionary;
-                }
-                return _references;
-            }
-        }
-
-        public virtual int Size => sizeof(TransactionType) + sizeof(byte) + Attributes.GetVarSize() + Inputs.GetVarSize() + Outputs.GetVarSize() + Scripts.GetVarSize();
-
-        /// <summary>
-        /// 系统费用
-        /// </summary>
-        public virtual Fixed8 SystemFee
-        {
-            get
-            {
-                if (Settings.Default.SystemFee.ContainsKey(Type))
-                    return Settings.Default.SystemFee[Type];
-                return Fixed8.Zero;
-            }
-        }
-
-        /// <summary>
-        /// 用指定的类型初始化Transaction对象
-        /// </summary>
-        /// <param name="type">交易类型</param>
-        protected Transaction(TransactionType type)
-        {
-            this.Type = type;
-        }
-
-        /// <summary>
-        /// 反序列化
-        /// </summary>
-        /// <param name="reader">数据来源</param>
-        void ISerializable.Deserialize(BinaryReader reader)
-        {
-            ((ISignable)this).DeserializeUnsigned(reader);
-            Scripts = reader.ReadSerializableArray<Witness>();
-            OnDeserialized();
-        }
-
-        /// <summary>
-        /// 反序列化交易中的额外数据
-        /// </summary>
-        /// <param name="reader">数据来源</param>
-        protected virtual void DeserializeExclusiveData(BinaryReader reader)
-        {
-        }
-
-        /// <summary>
-        /// 从指定的字节数组反序列化一笔交易
-        /// </summary>
-        /// <param name="value">字节数组</param>
-        /// <param name="offset">偏移量，反序列化从该偏移量处开始</param>
-        /// <returns>返回反序列化后的结果</returns>
-        public static Transaction DeserializeFrom(byte[] value, int offset = 0)
-        {
-            using (MemoryStream ms = new MemoryStream(value, offset, value.Length - offset, false))
-            using (BinaryReader reader = new BinaryReader(ms, Encoding.UTF8))
-            {
-                return DeserializeFrom(reader);
-            }
-        }
-
-        /// <summary>
-        /// 反序列化
-        /// </summary>
-        /// <param name="reader">数据来源</param>
-        /// <returns>返回反序列化后的结果</returns>
-        internal static Transaction DeserializeFrom(BinaryReader reader)
-        {
-            TransactionType type = (TransactionType)reader.ReadByte();
-            string typeName = string.Format("{0}.{1}", typeof(Transaction).Namespace, type);
-            Transaction transaction = typeof(Transaction).GetTypeInfo().Assembly.CreateInstance(typeName) as Transaction;
-            if (transaction == null)
-                throw new FormatException();
-            transaction.DeserializeUnsignedWithoutType(reader);
-            transaction.Scripts = reader.ReadSerializableArray<Witness>();
-            return transaction;
-        }
-
-        void ISignable.DeserializeUnsigned(BinaryReader reader)
-        {
-            if ((TransactionType)reader.ReadByte() != Type)
-                throw new FormatException();
-            DeserializeUnsignedWithoutType(reader);
-        }
-
-        private void DeserializeUnsignedWithoutType(BinaryReader reader)
-        {
-            Version = reader.ReadByte();
-            if (Version != 0)
-                throw new FormatException();
-            DeserializeExclusiveData(reader);
-            Attributes = reader.ReadSerializableArray<TransactionAttribute>();
-            Inputs = reader.ReadSerializableArray<CoinReference>();
-            Outputs = reader.ReadSerializableArray<TransactionOutput>(ushort.MaxValue + 1);
-        }
-
-        public bool Equals(Transaction other)
-        {
-            if (ReferenceEquals(null, other)) return false;
-            if (ReferenceEquals(this, other)) return true;
-            return Hash.Equals(other.Hash);
-        }
-
-        public override bool Equals(object obj)
-        {
-            return Equals(obj as Transaction);
-        }
-
-        public override int GetHashCode()
-        {
-            return Hash.GetHashCode();
-        }
-
-        byte[] IScriptContainer.GetMessage()
-        {
-            return this.GetHashData();
-        }
-
-        /// <summary>
-        /// 获取需要校验的脚本散列值
-        /// </summary>
-        /// <returns>返回需要校验的脚本散列值</returns>
-        public virtual UInt160[] GetScriptHashesForVerifying()
-        {
-            if (References == null) throw new InvalidOperationException();
-            HashSet<UInt160> hashes = new HashSet<UInt160>(Inputs.Select(p => References[p].ScriptHash));
-            hashes.UnionWith(Attributes.Where(p => p.Usage == TransactionAttributeUsage.Script).Select(p => new UInt160(p.Data)));
-            foreach (var group in Outputs.GroupBy(p => p.AssetId))
-            {
-                RegisterTransaction tx = Blockchain.Default.GetTransaction(group.Key) as RegisterTransaction;
-                if (tx == null) throw new InvalidOperationException();
-                if (tx.AssetType.HasFlag(AssetType.DutyFlag))
-                {
-                    hashes.UnionWith(group.Select(p => p.ScriptHash));
-                }
-            }
-            return hashes.OrderBy(p => p).ToArray();
-        }
-
-        /// <summary>
-        /// 获取交易后各资产的变化量
-        /// </summary>
-        /// <returns>返回交易后各资产的变化量</returns>
-        public IEnumerable<TransactionResult> GetTransactionResults()
-        {
-            if (References == null) return null;
-            return References.Values.Select(p => new
-            {
-                AssetId = p.AssetId,
-                Value = p.Value
-            }).Concat(Outputs.Select(p => new
-            {
-                AssetId = p.AssetId,
-                Value = -p.Value
-            })).GroupBy(p => p.AssetId, (k, g) => new TransactionResult
-            {
-                AssetId = k,
-                Amount = g.Sum(p => p.Value)
-            }).Where(p => p.Amount != Fixed8.Zero);
-        }
-
-        /// <summary>
-        /// 通知子类反序列化完毕
-        /// </summary>
-        protected virtual void OnDeserialized()
-        {
-        }
-
-        /// <summary>
-        /// 序列化
-        /// </summary>
-        /// <param name="writer">存放序列化后的结果</param>
-        void ISerializable.Serialize(BinaryWriter writer)
-        {
-            ((ISignable)this).SerializeUnsigned(writer);
-            writer.Write(Scripts);
-        }
-
-        /// <summary>
-        /// 序列化交易中的额外数据
-        /// </summary>
-        /// <param name="writer">存放序列化后的结果</param>
-        protected virtual void SerializeExclusiveData(BinaryWriter writer)
-        {
-        }
-
-        void ISignable.SerializeUnsigned(BinaryWriter writer)
-        {
-            writer.Write((byte)Type);
-            writer.Write(Version);
-            SerializeExclusiveData(writer);
-            writer.Write(Attributes);
-            writer.Write(Inputs);
-            writer.Write(Outputs);
-        }
-
-        byte[] IApiInterface.ToArray()
-        {
-            return this.ToArray();
-        }
-
-        /// <summary>
-        /// 变成json对象
-        /// </summary>
-        /// <returns>返回json对象</returns>
-        public virtual JObject ToJson()
-        {
-            JObject json = new JObject();
-            json["txid"] = Hash.ToString();
-            json["size"] = Size;
-            json["type"] = Type;
-            json["version"] = Version;
-            json["attributes"] = Attributes.Select(p => p.ToJson()).ToArray();
-            json["vin"] = Inputs.Select(p => p.ToJson()).ToArray();
-            json["vout"] = Outputs.Select((p, i) => p.ToJson((ushort)i)).ToArray();
-            json["scripts"] = Scripts.Select(p => p.ToJson()).ToArray();
-            return json;
-        }
-
-        bool IInventory.Verify()
-        {
-            return Verify(Enumerable.Empty<Transaction>());
-        }
-
-        /// <summary>
-        /// 验证交易
-        /// </summary>
-        /// <returns>返回验证的结果</returns>
-        public virtual bool Verify(IEnumerable<Transaction> mempool)
-        {
-            if (!Blockchain.Default.Ability.HasFlag(BlockchainAbility.UnspentIndexes) || !Blockchain.Default.Ability.HasFlag(BlockchainAbility.TransactionIndexes))
-                return false;
-            for (int i = 1; i < Inputs.Length; i++)
-                for (int j = 0; j < i; j++)
-                    if (Inputs[i].PrevHash == Inputs[j].PrevHash && Inputs[i].PrevIndex == Inputs[j].PrevIndex)
-                        return false;
-            if (mempool.Where(p => p != this).SelectMany(p => p.Inputs).Intersect(Inputs).Count() > 0)
-                return false;
-            if (Blockchain.Default.IsDoubleSpend(this))
-                return false;
-            foreach (var group in Outputs.GroupBy(p => p.AssetId))
-            {
-                RegisterTransaction asset = Blockchain.Default.GetTransaction(group.Key) as RegisterTransaction;
-                if (asset == null) return false;
-                foreach (TransactionOutput output in group)
-                    if (output.Value.GetData() % (long)Math.Pow(10, 8 - asset.Precision) != 0)
-                        return false;
-            }
-            TransactionResult[] results = GetTransactionResults()?.ToArray();
-            if (results == null) return false;
-            TransactionResult[] results_destroy = results.Where(p => p.Amount > Fixed8.Zero).ToArray();
-            if (results_destroy.Length > 1) return false;
-            if (results_destroy.Length == 1 && results_destroy[0].AssetId != Blockchain.AntCoin.Hash)
-                return false;
-            if (SystemFee > Fixed8.Zero && (results_destroy.Length == 0 || results_destroy[0].Amount < SystemFee))
-                return false;
-            TransactionResult[] results_issue = results.Where(p => p.Amount < Fixed8.Zero).ToArray();
-            switch (Type)
-            {
-                case TransactionType.MinerTransaction:
-                case TransactionType.ClaimTransaction:
-                    if (results_issue.Any(p => p.AssetId != Blockchain.AntCoin.Hash))
-                        return false;
-                    break;
-                case TransactionType.IssueTransaction:
-                    if (results_issue.Any(p => p.AssetId == Blockchain.AntCoin.Hash))
-                        return false;
-                    break;
-                default:
-                    if (results_issue.Length > 0)
-                        return false;
-                    break;
-            }
-            if (Attributes.Count(p => p.Usage == TransactionAttributeUsage.ECDH02 || p.Usage == TransactionAttributeUsage.ECDH03) > 1)
-                return false;
-            if (Attributes.Count(p => p.Usage == TransactionAttributeUsage.Vote) > 1024)
-                return false;
-            if (Attributes.Where(p => p.Usage == TransactionAttributeUsage.Vote).Select(p => new UInt256(p.Data)).Distinct().Count() != Attributes.Count(p => p.Usage == TransactionAttributeUsage.Vote))
-                return false;
-            if (Attributes.Any(p => p.Usage == TransactionAttributeUsage.Vote))
-            {
-                if (!Blockchain.Default.Ability.HasFlag(BlockchainAbility.UnspentIndexes))
-                    return false;
-                if (Outputs.All(p => !p.AssetId.Equals(Blockchain.AntShare.Hash)))
-                    return false;
-                HashSet<ECPoint> pubkeys = new HashSet<ECPoint>();
-                foreach (UInt256 vote in Attributes.Where(p => p.Usage == TransactionAttributeUsage.Vote).Select(p => new UInt256(p.Data)))
-                {
-                    EnrollmentTransaction tx = Blockchain.Default.GetTransaction(vote) as EnrollmentTransaction;
-                    if (tx == null) return false;
-                    if (!Blockchain.Default.ContainsUnspent(vote, 0)) return false;
-                    if (!pubkeys.Add(tx.PublicKey)) return false;
-                }
-            }
-            return this.VerifySignature();
-        }
-    }
-}
+using AntShares.Cryptography;
+using AntShares.Cryptography.ECC;
+using AntShares.IO;
+using AntShares.IO.Json;
+using AntShares.Network;
+using AntShares.VM;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+
+namespace AntShares.Core
+{
+    /// <summary>
+    /// 一切交易的基类
+    /// </summary>
+    public abstract class Transaction : IEquatable<Transaction>, IInventory
+    {
+        /// <summary>
+        /// 交易类型
+        /// </summary>
+        public readonly TransactionType Type;
+        /// <summary>
+        /// 版本
+        /// </summary>
+        public byte Version;
+        /// <summary>
+        /// 该交易所具备的额外特性
+        /// </summary>
+        public TransactionAttribute[] Attributes;
+        /// <summary>
+        /// 输入列表
+        /// </summary>
+        public CoinReference[] Inputs;
+        /// <summary>
+        /// 输出列表
+        /// </summary>
+        public TransactionOutput[] Outputs;
+        /// <summary>
+        /// 用于验证该交易的脚本列表
+        /// </summary>
+        public Witness[] Scripts { get; set; }
+
+        private UInt256 _hash = null;
+        public UInt256 Hash
+        {
+            get
+            {
+                if (_hash == null)
+                {
+                    _hash = new UInt256(this.GetHashData().Sha256().Sha256());
+                }
+                return _hash;
+            }
+        }
+
+        /// <summary>
+        /// 清单类型
+        /// </summary>
+        InventoryType IInventory.InventoryType => InventoryType.TX;
+
+        private Fixed8 _network_fee = -Fixed8.Satoshi;
+        public Fixed8 NetworkFee
+        {
+            get
+            {
+                if (_network_fee == -Fixed8.Satoshi)
+                {
+                    Fixed8 input = References.Values.Where(p => p.AssetId.Equals(Blockchain.AntCoin.Hash)).Sum(p => p.Value);
+                    Fixed8 output = Outputs.Where(p => p.AssetId.Equals(Blockchain.AntCoin.Hash)).Sum(p => p.Value);
+                    _network_fee = input - output - SystemFee;
+                }
+                return _network_fee;
+            }
+        }
+
+        private IReadOnlyDictionary<CoinReference, TransactionOutput> _references;
+        /// <summary>
+        /// 每一个交易输入所引用的交易输出
+        /// </summary>
+        public IReadOnlyDictionary<CoinReference, TransactionOutput> References
+        {
+            get
+            {
+                if (_references == null)
+                {
+                    Dictionary<CoinReference, TransactionOutput> dictionary = new Dictionary<CoinReference, TransactionOutput>();
+                    foreach (var group in Inputs.GroupBy(p => p.PrevHash))
+                    {
+                        Transaction tx = Blockchain.Default.GetTransaction(group.Key);
+                        if (tx == null) return null;
+                        foreach (var reference in group.Select(p => new
+                        {
+                            Input = p,
+                            Output = tx.Outputs[p.PrevIndex]
+                        }))
+                        {
+                            dictionary.Add(reference.Input, reference.Output);
+                        }
+                    }
+                    _references = dictionary;
+                }
+                return _references;
+            }
+        }
+
+        public virtual int Size => sizeof(TransactionType) + sizeof(byte) + Attributes.GetVarSize() + Inputs.GetVarSize() + Outputs.GetVarSize() + Scripts.GetVarSize();
+
+        /// <summary>
+        /// 系统费用
+        /// </summary>
+        public virtual Fixed8 SystemFee
+        {
+            get
+            {
+                if (Settings.Default.SystemFee.ContainsKey(Type))
+                    return Settings.Default.SystemFee[Type];
+                return Fixed8.Zero;
+            }
+        }
+
+        /// <summary>
+        /// 用指定的类型初始化Transaction对象
+        /// </summary>
+        /// <param name="type">交易类型</param>
+        protected Transaction(TransactionType type)
+        {
+            this.Type = type;
+        }
+
+        /// <summary>
+        /// 反序列化
+        /// </summary>
+        /// <param name="reader">数据来源</param>
+        void ISerializable.Deserialize(BinaryReader reader)
+        {
+            ((ISignable)this).DeserializeUnsigned(reader);
+            Scripts = reader.ReadSerializableArray<Witness>();
+            OnDeserialized();
+        }
+
+        /// <summary>
+        /// 反序列化交易中的额外数据
+        /// </summary>
+        /// <param name="reader">数据来源</param>
+        protected virtual void DeserializeExclusiveData(BinaryReader reader)
+        {
+        }
+
+        /// <summary>
+        /// 从指定的字节数组反序列化一笔交易
+        /// </summary>
+        /// <param name="value">字节数组</param>
+        /// <param name="offset">偏移量，反序列化从该偏移量处开始</param>
+        /// <returns>返回反序列化后的结果</returns>
+        public static Transaction DeserializeFrom(byte[] value, int offset = 0)
+        {
+            using (MemoryStream ms = new MemoryStream(value, offset, value.Length - offset, false))
+            using (BinaryReader reader = new BinaryReader(ms, Encoding.UTF8))
+            {
+                return DeserializeFrom(reader);
+            }
+        }
+
+        /// <summary>
+        /// 反序列化
+        /// </summary>
+        /// <param name="reader">数据来源</param>
+        /// <returns>返回反序列化后的结果</returns>
+        internal static Transaction DeserializeFrom(BinaryReader reader)
+        {
+            TransactionType type = (TransactionType)reader.ReadByte();
+            string typeName = string.Format("{0}.{1}", typeof(Transaction).Namespace, type);
+            Transaction transaction = typeof(Transaction).GetTypeInfo().Assembly.CreateInstance(typeName) as Transaction;
+            if (transaction == null)
+                throw new FormatException();
+            transaction.DeserializeUnsignedWithoutType(reader);
+            transaction.Scripts = reader.ReadSerializableArray<Witness>();
+            return transaction;
+        }
+
+        void ISignable.DeserializeUnsigned(BinaryReader reader)
+        {
+            if ((TransactionType)reader.ReadByte() != Type)
+                throw new FormatException();
+            DeserializeUnsignedWithoutType(reader);
+        }
+
+        private void DeserializeUnsignedWithoutType(BinaryReader reader)
+        {
+            Version = reader.ReadByte();
+            if (Version != 0)
+                throw new FormatException();
+            DeserializeExclusiveData(reader);
+            Attributes = reader.ReadSerializableArray<TransactionAttribute>();
+            Inputs = reader.ReadSerializableArray<CoinReference>();
+            Outputs = reader.ReadSerializableArray<TransactionOutput>(ushort.MaxValue + 1);
+        }
+
+        public bool Equals(Transaction other)
+        {
+            if (ReferenceEquals(null, other)) return false;
+            if (ReferenceEquals(this, other)) return true;
+            return Hash.Equals(other.Hash);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return Equals(obj as Transaction);
+        }
+
+        public override int GetHashCode()
+        {
+            return Hash.GetHashCode();
+        }
+
+        byte[] IScriptContainer.GetMessage()
+        {
+            return this.GetHashData();
+        }
+
+        /// <summary>
+        /// 获取需要校验的脚本散列值
+        /// </summary>
+        /// <returns>返回需要校验的脚本散列值</returns>
+        public virtual UInt160[] GetScriptHashesForVerifying()
+        {
+            if (References == null) throw new InvalidOperationException();
+            HashSet<UInt160> hashes = new HashSet<UInt160>(Inputs.Select(p => References[p].ScriptHash));
+            hashes.UnionWith(Attributes.Where(p => p.Usage == TransactionAttributeUsage.Script).Select(p => new UInt160(p.Data)));
+            foreach (var group in Outputs.GroupBy(p => p.AssetId))
+            {
+                RegisterTransaction tx = Blockchain.Default.GetTransaction(group.Key) as RegisterTransaction;
+                if (tx == null) throw new InvalidOperationException();
+                if (tx.AssetType.HasFlag(AssetType.DutyFlag))
+                {
+                    hashes.UnionWith(group.Select(p => p.ScriptHash));
+                }
+            }
+            return hashes.OrderBy(p => p).ToArray();
+        }
+
+        /// <summary>
+        /// 获取交易后各资产的变化量
+        /// </summary>
+        /// <returns>返回交易后各资产的变化量</returns>
+        public IEnumerable<TransactionResult> GetTransactionResults()
+        {
+            if (References == null) return null;
+            return References.Values.Select(p => new
+            {
+                AssetId = p.AssetId,
+                Value = p.Value
+            }).Concat(Outputs.Select(p => new
+            {
+                AssetId = p.AssetId,
+                Value = -p.Value
+            })).GroupBy(p => p.AssetId, (k, g) => new TransactionResult
+            {
+                AssetId = k,
+                Amount = g.Sum(p => p.Value)
+            }).Where(p => p.Amount != Fixed8.Zero);
+        }
+
+        /// <summary>
+        /// 通知子类反序列化完毕
+        /// </summary>
+        protected virtual void OnDeserialized()
+        {
+        }
+
+        /// <summary>
+        /// 序列化
+        /// </summary>
+        /// <param name="writer">存放序列化后的结果</param>
+        void ISerializable.Serialize(BinaryWriter writer)
+        {
+            ((ISignable)this).SerializeUnsigned(writer);
+            writer.Write(Scripts);
+        }
+
+        /// <summary>
+        /// 序列化交易中的额外数据
+        /// </summary>
+        /// <param name="writer">存放序列化后的结果</param>
+        protected virtual void SerializeExclusiveData(BinaryWriter writer)
+        {
+        }
+
+        void ISignable.SerializeUnsigned(BinaryWriter writer)
+        {
+            writer.Write((byte)Type);
+            writer.Write(Version);
+            SerializeExclusiveData(writer);
+            writer.Write(Attributes);
+            writer.Write(Inputs);
+            writer.Write(Outputs);
+        }
+
+        byte[] IApiInterface.ToArray()
+        {
+            return this.ToArray();
+        }
+
+        /// <summary>
+        /// 变成json对象
+        /// </summary>
+        /// <returns>返回json对象</returns>
+        public virtual JObject ToJson()
+        {
+            JObject json = new JObject();
+            json["txid"] = Hash.ToString();
+            json["size"] = Size;
+            json["type"] = Type;
+            json["version"] = Version;
+            json["attributes"] = Attributes.Select(p => p.ToJson()).ToArray();
+            json["vin"] = Inputs.Select(p => p.ToJson()).ToArray();
+            json["vout"] = Outputs.Select((p, i) => p.ToJson((ushort)i)).ToArray();
+            json["sys_fee"] = SystemFee.ToString();
+            json["net_fee"] = NetworkFee.ToString();
+            json["scripts"] = Scripts.Select(p => p.ToJson()).ToArray();
+            return json;
+        }
+
+        bool IInventory.Verify()
+        {
+            return Verify(Enumerable.Empty<Transaction>());
+        }
+
+        /// <summary>
+        /// 验证交易
+        /// </summary>
+        /// <returns>返回验证的结果</returns>
+        public virtual bool Verify(IEnumerable<Transaction> mempool)
+        {
+            if (!Blockchain.Default.Ability.HasFlag(BlockchainAbility.UnspentIndexes) || !Blockchain.Default.Ability.HasFlag(BlockchainAbility.TransactionIndexes))
+                return false;
+            for (int i = 1; i < Inputs.Length; i++)
+                for (int j = 0; j < i; j++)
+                    if (Inputs[i].PrevHash == Inputs[j].PrevHash && Inputs[i].PrevIndex == Inputs[j].PrevIndex)
+                        return false;
+            if (mempool.Where(p => p != this).SelectMany(p => p.Inputs).Intersect(Inputs).Count() > 0)
+                return false;
+            if (Blockchain.Default.IsDoubleSpend(this))
+                return false;
+            foreach (var group in Outputs.GroupBy(p => p.AssetId))
+            {
+                RegisterTransaction asset = Blockchain.Default.GetTransaction(group.Key) as RegisterTransaction;
+                if (asset == null) return false;
+                foreach (TransactionOutput output in group)
+                    if (output.Value.GetData() % (long)Math.Pow(10, 8 - asset.Precision) != 0)
+                        return false;
+            }
+            TransactionResult[] results = GetTransactionResults()?.ToArray();
+            if (results == null) return false;
+            TransactionResult[] results_destroy = results.Where(p => p.Amount > Fixed8.Zero).ToArray();
+            if (results_destroy.Length > 1) return false;
+            if (results_destroy.Length == 1 && results_destroy[0].AssetId != Blockchain.AntCoin.Hash)
+                return false;
+            if (SystemFee > Fixed8.Zero && (results_destroy.Length == 0 || results_destroy[0].Amount < SystemFee))
+                return false;
+            TransactionResult[] results_issue = results.Where(p => p.Amount < Fixed8.Zero).ToArray();
+            switch (Type)
+            {
+                case TransactionType.MinerTransaction:
+                case TransactionType.ClaimTransaction:
+                    if (results_issue.Any(p => p.AssetId != Blockchain.AntCoin.Hash))
+                        return false;
+                    break;
+                case TransactionType.IssueTransaction:
+                    if (results_issue.Any(p => p.AssetId == Blockchain.AntCoin.Hash))
+                        return false;
+                    break;
+                default:
+                    if (results_issue.Length > 0)
+                        return false;
+                    break;
+            }
+            if (Attributes.Count(p => p.Usage == TransactionAttributeUsage.ECDH02 || p.Usage == TransactionAttributeUsage.ECDH03) > 1)
+                return false;
+            if (Attributes.Count(p => p.Usage == TransactionAttributeUsage.Vote) > 1024)
+                return false;
+            if (Attributes.Where(p => p.Usage == TransactionAttributeUsage.Vote).Select(p => new UInt256(p.Data)).Distinct().Count() != Attributes.Count(p => p.Usage == TransactionAttributeUsage.Vote))
+                return false;
+            if (Attributes.Any(p => p.Usage == TransactionAttributeUsage.Vote))
+            {
+                if (!Blockchain.Default.Ability.HasFlag(BlockchainAbility.UnspentIndexes))
+                    return false;
+                if (Outputs.All(p => !p.AssetId.Equals(Blockchain.AntShare.Hash)))
+                    return false;
+                HashSet<ECPoint> pubkeys = new HashSet<ECPoint>();
+                foreach (UInt256 vote in Attributes.Where(p => p.Usage == TransactionAttributeUsage.Vote).Select(p => new UInt256(p.Data)))
+                {
+                    EnrollmentTransaction tx = Blockchain.Default.GetTransaction(vote) as EnrollmentTransaction;
+                    if (tx == null) return false;
+                    if (!Blockchain.Default.ContainsUnspent(vote, 0)) return false;
+                    if (!pubkeys.Add(tx.PublicKey)) return false;
+                }
+            }
+            return this.VerifySignature();
+        }
+    }
+}
diff --git a/src/AntShares/Network/InventoryReceivingEventArgs.cs b/src/AntShares/Network/InventoryReceivingEventArgs.cs
new file mode 100644
index 0000000000..1ecebba2b4
--- /dev/null
+++ b/src/AntShares/Network/InventoryReceivingEventArgs.cs
@@ -0,0 +1,14 @@
+using System.ComponentModel;
+
+namespace AntShares.Network
+{
+    public class InventoryReceivingEventArgs : CancelEventArgs
+    {
+        public IInventory Inventory { get; }
+
+        public InventoryReceivingEventArgs(IInventory inventory)
+        {
+            this.Inventory = inventory;
+        }
+    }
+}
diff --git a/src/AntShares/Network/LocalNode.cs b/src/AntShares/Network/LocalNode.cs
index f71c9b9439..b327b77f04 100644
--- a/src/AntShares/Network/LocalNode.cs
+++ b/src/AntShares/Network/LocalNode.cs
@@ -18,12 +18,13 @@ namespace AntShares.Network
 {
     public class LocalNode : IDisposable
     {
-        public static event EventHandler<IInventory> NewInventory;
+        public static event EventHandler<InventoryReceivingEventArgs> InventoryReceiving;
+        public static event EventHandler<IInventory> InventoryReceived;
 
         public const uint PROTOCOL_VERSION = 0;
         private const int CONNECTED_MAX = 10;
         private const int UNCONNECTED_MAX = 1000;
-        public const int MemoryPoolSize = 15000;
+        public const int MemoryPoolSize = 30000;
 
         private static readonly Dictionary<UInt256, Transaction> mem_pool = new Dictionary<UInt256, Transaction>();
         private readonly HashSet<Transaction> temp_pool = new HashSet<Transaction>();
@@ -120,6 +121,7 @@ private void AddTransactionLoop()
                 Transaction[] transactions;
                 lock (temp_pool)
                 {
+                    if (temp_pool.Count == 0) continue;
                     transactions = temp_pool.ToArray();
                     temp_pool.Clear();
                 }
@@ -127,16 +129,21 @@ private void AddTransactionLoop()
                 lock (mem_pool)
                 {
                     transactions = transactions.Where(p => !mem_pool.ContainsKey(p.Hash) && !Blockchain.Default.ContainsTransaction(p.Hash)).ToArray();
+                    if (transactions.Length == 0) continue;
                     transactions.AsParallel().ForAll(tx =>
                     {
                         if (tx.Verify(mem_pool.Values.Concat(transactions)))
                             verified.Add(tx);
                     });
+                    if (verified.Count == 0) continue;
                     foreach (Transaction tx in verified)
                         mem_pool.Add(tx.Hash, tx);
                     CheckMemPool();
                 }
                 RelayDirectly(verified);
+                if (InventoryReceived != null)
+                    foreach (Transaction tx in verified)
+                        InventoryReceived(this, tx);
             }
         }
 
@@ -169,11 +176,7 @@ private static void Blockchain_PersistCompleted(object sender, Block block)
         private static void CheckMemPool()
         {
             if (mem_pool.Count <= MemoryPoolSize) return;
-            UInt256[] hashes = mem_pool.Values.AsParallel().Select(tx => new
-            {
-                Hash = tx.Hash,
-                Fee = (tx.References.Values.Where(p => p.AssetId.Equals(Blockchain.AntCoin.Hash)).Sum(p => p.Value) - tx.Outputs.Where(p => p.AssetId.Equals(Blockchain.AntCoin.Hash)).Sum(p => p.Value) - tx.SystemFee) / tx.Size
-            }).OrderBy(p => p.Fee).Take(mem_pool.Count - MemoryPoolSize).Select(p => p.Hash).ToArray();
+            UInt256[] hashes = mem_pool.Values.AsParallel().OrderBy(p => p.NetworkFee / p.Size).Take(mem_pool.Count - MemoryPoolSize).Select(p => p.Hash).ToArray();
             foreach (UInt256 hash in hashes)
                 mem_pool.Remove(hash);
         }
@@ -370,6 +373,9 @@ public bool Relay(IInventory inventory)
             {
                 if (!KnownHashes.Add(inventory.Hash)) return false;
             }
+            InventoryReceivingEventArgs args = new InventoryReceivingEventArgs(inventory);
+            InventoryReceiving?.Invoke(this, args);
+            if (args.Cancel) return false;
             if (inventory is Block)
             {
                 if (Blockchain.Default == null) return false;
@@ -386,7 +392,7 @@ public bool Relay(IInventory inventory)
                 if (!inventory.Verify()) return false;
             }
             bool relayed = RelayDirectly(inventory);
-            NewInventory?.Invoke(this, inventory);
+            InventoryReceived?.Invoke(this, inventory);
             return relayed;
         }
 
@@ -446,6 +452,9 @@ private void RemoteNode_InventoryReceived(object sender, IInventory inventory)
                 {
                     if (!KnownHashes.Add(inventory.Hash)) return;
                 }
+                InventoryReceivingEventArgs args = new InventoryReceivingEventArgs(inventory);
+                InventoryReceiving?.Invoke(this, args);
+                if (args.Cancel) return;
                 lock (temp_pool)
                 {
                     temp_pool.Add((Transaction)inventory);
diff --git a/src/AntShares/Network/RemoteNode.cs b/src/AntShares/Network/RemoteNode.cs
index a3c30f8955..88e6e680d4 100644
--- a/src/AntShares/Network/RemoteNode.cs
+++ b/src/AntShares/Network/RemoteNode.cs
@@ -365,7 +365,7 @@ private void RunProtocol()
             }
             lock (localNode.connectedPeers)
             {
-                if (localNode.connectedPeers.Where(p => p != this).Any(p => p.RemoteEndpoint.Address.Equals(RemoteEndpoint.Address) && p.Version.Nonce == Version.Nonce))
+                if (localNode.connectedPeers.Where(p => p != this).Any(p => p.RemoteEndpoint.Address.Equals(RemoteEndpoint.Address) && p.Version?.Nonce == Version.Nonce))
                 {
                     Disconnect(false);
                     return;