diff --git a/neo/Consensus/ConsensusService.cs b/neo/Consensus/ConsensusService.cs
index cb6e6e1dc4..eb30880022 100644
--- a/neo/Consensus/ConsensusService.cs
+++ b/neo/Consensus/ConsensusService.cs
@@ -1,661 +1,660 @@
-using Akka.Actor;
-using Akka.Configuration;
-using Neo.Cryptography;
-using Neo.IO;
-using Neo.IO.Actors;
-using Neo.Ledger;
-using Neo.Network.P2P;
-using Neo.Network.P2P.Payloads;
-using Neo.Persistence;
-using Neo.Plugins;
-using Neo.SmartContract.Native;
-using Neo.Wallets;
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-
-namespace Neo.Consensus
-{
-    public sealed class ConsensusService : UntypedActor
-    {
-        public class Start { public bool IgnoreRecoveryLogs; }
-        public class SetViewNumber { public byte ViewNumber; }
-        internal class Timer { public uint Height; public byte ViewNumber; }
-
-        private readonly ConsensusContext context;
-        private readonly IActorRef localNode;
-        private readonly IActorRef taskManager;
-        private ICancelable timer_token;
-        private DateTime block_received_time;
-        private bool started = false;
-
-        /// <summary>
-        /// This will record the information from last scheduled timer
-        /// </summary>
-        private DateTime clock_started = TimeProvider.Current.UtcNow;
-        private TimeSpan expected_delay = TimeSpan.Zero;
-
-        /// <summary>
-        /// This will be cleared every block (so it will not grow out of control, but is used to prevent repeatedly
-        /// responding to the same message.
-        /// </summary>
-        private readonly HashSet<UInt256> knownHashes = new HashSet<UInt256>();
-        /// <summary>
-        /// This variable is only true during OnRecoveryMessageReceived
-        /// </summary>
-        private bool isRecovering = false;
-
-        public ConsensusService(IActorRef localNode, IActorRef taskManager, Store store, Wallet wallet)
-            : this(localNode, taskManager, new ConsensusContext(wallet, store))
-        {
-        }
-
-        internal ConsensusService(IActorRef localNode, IActorRef taskManager, ConsensusContext context)
-        {
-            this.localNode = localNode;
-            this.taskManager = taskManager;
-            this.context = context;
-            Context.System.EventStream.Subscribe(Self, typeof(Blockchain.PersistCompleted));
-        }
-
-        private bool AddTransaction(Transaction tx, bool verify)
-        {
-            if (verify && !tx.Verify(context.Snapshot, context.Transactions.Values))
-            {
-                Log($"Invalid transaction: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}", LogLevel.Warning);
-                RequestChangeView(ChangeViewReason.TxInvalid);
-                return false;
-            }
-            if (!NativeContract.Policy.CheckPolicy(tx, context.Snapshot))
-            {
-                Log($"reject tx: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}", LogLevel.Warning);
-                RequestChangeView(ChangeViewReason.TxRejectedByPolicy);
-                return false;
-            }
-            context.Transactions[tx.Hash] = tx;
-            if (context.TransactionHashes.Length == context.Transactions.Count)
-            {
-                // if we are the primary for this view, but acting as a backup because we recovered our own
-                // previously sent prepare request, then we don't want to send a prepare response.
-                if (context.IsPrimary || context.WatchOnly) return true;
+using Akka.Actor;
+using Akka.Configuration;
+using Neo.Cryptography;
+using Neo.IO;
+using Neo.IO.Actors;
+using Neo.Ledger;
+using Neo.Network.P2P;
+using Neo.Network.P2P.Payloads;
+using Neo.Persistence;
+using Neo.Plugins;
+using Neo.SmartContract.Native;
+using Neo.Wallets;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+
+namespace Neo.Consensus
+{
+    public sealed class ConsensusService : UntypedActor
+    {
+        public class Start { public bool IgnoreRecoveryLogs; }
+        public class SetViewNumber { public byte ViewNumber; }
+        internal class Timer { public uint Height; public byte ViewNumber; }
+
+        private readonly ConsensusContext context;
+        private readonly IActorRef localNode;
+        private readonly IActorRef taskManager;
+        private ICancelable timer_token;
+        private DateTime block_received_time;
+        private bool started = false;
+
+        /// <summary>
+        /// This will record the information from last scheduled timer
+        /// </summary>
+        private DateTime clock_started = TimeProvider.Current.UtcNow;
+        private TimeSpan expected_delay = TimeSpan.Zero;
+
+        /// <summary>
+        /// This will be cleared every block (so it will not grow out of control, but is used to prevent repeatedly
+        /// responding to the same message.
+        /// </summary>
+        private readonly HashSet<UInt256> knownHashes = new HashSet<UInt256>();
+        /// <summary>
+        /// This variable is only true during OnRecoveryMessageReceived
+        /// </summary>
+        private bool isRecovering = false;
 
-                // Check policy
+        public ConsensusService(IActorRef localNode, IActorRef taskManager, Store store, Wallet wallet)
+            : this(localNode, taskManager, new ConsensusContext(wallet, store))
+        {
+        }
 
+        internal ConsensusService(IActorRef localNode, IActorRef taskManager, ConsensusContext context)
+        {
+            this.localNode = localNode;
+            this.taskManager = taskManager;
+            this.context = context;
+            Context.System.EventStream.Subscribe(Self, typeof(Blockchain.PersistCompleted));
+        }
+
+        private bool AddTransaction(Transaction tx, bool verify)
+        {
+            if (verify && !tx.Verify(context.Snapshot, context.Transactions.Values))
+            {
+                Log($"Invalid transaction: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}", LogLevel.Warning);
+                RequestChangeView(ChangeViewReason.TxInvalid);
+                return false;
+            }
+            if (!NativeContract.Policy.CheckPolicy(tx, context.Snapshot))
+            {
+                Log($"reject tx: {tx.Hash}{Environment.NewLine}{tx.ToArray().ToHexString()}", LogLevel.Warning);
+                RequestChangeView(ChangeViewReason.TxRejectedByPolicy);
+                return false;
+            }
+            context.Transactions[tx.Hash] = tx;
+            if (context.TransactionHashes.Length == context.Transactions.Count)
+            {
+                // if we are the primary for this view, but acting as a backup because we recovered our own
+                // previously sent prepare request, then we don't want to send a prepare response.
+                if (context.IsPrimary || context.WatchOnly) return true;
+
+                // Check maximum block size via Native.Contract policy
                 if (context.GetExpectedBlockSize() > NativeContract.Policy.GetMaxBlockSize(context.Snapshot))
                 {
                     Log($"rejected block: {context.Block.Index}{Environment.NewLine} The size exceed the policy", LogLevel.Warning);
                     RequestChangeView(ChangeViewReason.BlockRejectedByPolicy);
                     return false;
-                }
-
-                // Timeout extension due to prepare response sent
-                // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
-                ExtendTimerByFactor(2);
-
-                Log($"send prepare response");
-                localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakePrepareResponse() });
-                CheckPreparations();
-            }
-            return true;
-        }
-
-        private void ChangeTimer(TimeSpan delay)
-        {
-            clock_started = TimeProvider.Current.UtcNow;
-            expected_delay = delay;
-            timer_token.CancelIfNotNull();
-            timer_token = Context.System.Scheduler.ScheduleTellOnceCancelable(delay, Self, new Timer
-            {
-                Height = context.Block.Index,
-                ViewNumber = context.ViewNumber
-            }, ActorRefs.NoSender);
-        }
-
-        private void CheckCommits()
-        {
-            if (context.CommitPayloads.Count(p => p?.ConsensusMessage.ViewNumber == context.ViewNumber) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
-            {
-                Block block = context.CreateBlock();
-                Log($"relay block: height={block.Index} hash={block.Hash} tx={block.Transactions.Length}");
-                localNode.Tell(new LocalNode.Relay { Inventory = block });
-            }
-        }
-
-        private void CheckExpectedView(byte viewNumber)
-        {
-            if (context.ViewNumber >= viewNumber) return;
-            // if there are `M` change view payloads with NewViewNumber greater than viewNumber, then, it is safe to move
-            if (context.ChangeViewPayloads.Count(p => p != null && p.GetDeserializedMessage<ChangeView>().NewViewNumber >= viewNumber) >= context.M)
-            {
-                if (!context.WatchOnly)
-                {
-                    ChangeView message = context.ChangeViewPayloads[context.MyIndex]?.GetDeserializedMessage<ChangeView>();
-                    // Communicate the network about my agreement to move to `viewNumber`
-                    // if my last change view payload, `message`, has NewViewNumber lower than current view to change
-                    if (message is null || message.NewViewNumber < viewNumber)
-                        localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeChangeView(ChangeViewReason.ChangeAgreement) });
-                }
-                InitializeConsensus(viewNumber);
-            }
-        }
-
-        private void CheckPreparations()
-        {
-            if (context.PreparationPayloads.Count(p => p != null) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
-            {
-                ConsensusPayload payload = context.MakeCommit();
-                Log($"send commit");
-                context.Save();
-                localNode.Tell(new LocalNode.SendDirectly { Inventory = payload });
-                // Set timer, so we will resend the commit in case of a networking issue
-                ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock));
-                CheckCommits();
-            }
-        }
-
-        private void InitializeConsensus(byte viewNumber)
-        {
-            context.Reset(viewNumber);
-            if (viewNumber > 0)
-                Log($"changeview: view={viewNumber} primary={context.Validators[context.GetPrimaryIndex((byte)(viewNumber - 1u))]}", LogLevel.Warning);
-            Log($"initialize: height={context.Block.Index} view={viewNumber} index={context.MyIndex} role={(context.IsPrimary ? "Primary" : context.WatchOnly ? "WatchOnly" : "Backup")}");
-            if (context.WatchOnly) return;
-            if (context.IsPrimary)
-            {
-                if (isRecovering)
-                {
-                    ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (viewNumber + 1)));
-                }
-                else
-                {
-                    TimeSpan span = TimeProvider.Current.UtcNow - block_received_time;
-                    if (span >= Blockchain.TimePerBlock)
-                        ChangeTimer(TimeSpan.Zero);
-                    else
-                        ChangeTimer(Blockchain.TimePerBlock - span);
-                }
-            }
-            else
-            {
-                ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (viewNumber + 1)));
-            }
-        }
-
-        private void Log(string message, LogLevel level = LogLevel.Info)
-        {
-            Console.WriteLine($"[{DateTime.Now.TimeOfDay:hh\\:mm\\:ss\\.fff}] {message}");
-            Plugin.Log(nameof(ConsensusService), level, message);
-        }
-
-        private void OnChangeViewReceived(ConsensusPayload payload, ChangeView message)
-        {
-            if (message.NewViewNumber <= context.ViewNumber)
-                OnRecoveryRequestReceived(payload);
-
-            if (context.CommitSent) return;
-
-            var expectedView = context.ChangeViewPayloads[payload.ValidatorIndex]?.GetDeserializedMessage<ChangeView>().NewViewNumber ?? (byte)0;
-            if (message.NewViewNumber <= expectedView)
-                return;
-
-            Log($"{nameof(OnChangeViewReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex} nv={message.NewViewNumber}");
-            context.ChangeViewPayloads[payload.ValidatorIndex] = payload;
-            CheckExpectedView(message.NewViewNumber);
-        }
-
-        private void OnCommitReceived(ConsensusPayload payload, Commit commit)
-        {
-            ref ConsensusPayload existingCommitPayload = ref context.CommitPayloads[payload.ValidatorIndex];
-            if (existingCommitPayload != null)
-            {
-                if (existingCommitPayload.Hash != payload.Hash)
-                    Log($"{nameof(OnCommitReceived)}: different commit from validator! height={payload.BlockIndex} index={payload.ValidatorIndex} view={commit.ViewNumber} existingView={existingCommitPayload.ConsensusMessage.ViewNumber}", LogLevel.Warning);
-                return;
-            }
-
-            // Timeout extension: commit has been received with success
-            // around 4*15s/M=60.0s/5=12.0s ~ 80% block time (for M=5)
-            ExtendTimerByFactor(4);
-
-            if (commit.ViewNumber == context.ViewNumber)
-            {
-                Log($"{nameof(OnCommitReceived)}: height={payload.BlockIndex} view={commit.ViewNumber} index={payload.ValidatorIndex} nc={context.CountCommitted} nf={context.CountFailed}");
-
-                byte[] hashData = context.EnsureHeader()?.GetHashData();
-                if (hashData == null)
-                {
-                    existingCommitPayload = payload;
-                }
-                else if (Crypto.Default.VerifySignature(hashData, commit.Signature,
-                    context.Validators[payload.ValidatorIndex].EncodePoint(false)))
-                {
-                    existingCommitPayload = payload;
-                    CheckCommits();
-                }
-                return;
-            }
-            // Receiving commit from another view
-            Log($"{nameof(OnCommitReceived)}: record commit for different view={commit.ViewNumber} index={payload.ValidatorIndex} height={payload.BlockIndex}");
-            existingCommitPayload = payload;
-        }
-
-        // this function increases existing timer (never decreases) with a value proportional to `maxDelayInBlockTimes`*`Blockchain.MillisecondsPerBlock`
-        private void ExtendTimerByFactor(int maxDelayInBlockTimes)
-        {
-            TimeSpan nextDelay = expected_delay - (TimeProvider.Current.UtcNow - clock_started) + TimeSpan.FromMilliseconds(maxDelayInBlockTimes * Blockchain.MillisecondsPerBlock / context.M);
-            if (!context.WatchOnly && !context.ViewChanging && !context.CommitSent && (nextDelay > TimeSpan.Zero))
-                ChangeTimer(nextDelay);
-        }
-
-        private void OnConsensusPayload(ConsensusPayload payload)
-        {
-            if (context.BlockSent) return;
-            if (payload.Version != context.Block.Version) return;
-            if (payload.PrevHash != context.Block.PrevHash || payload.BlockIndex != context.Block.Index)
-            {
-                if (context.Block.Index < payload.BlockIndex)
-                {
-                    Log($"chain sync: expected={payload.BlockIndex} current={context.Block.Index - 1} nodes={LocalNode.Singleton.ConnectedCount}", LogLevel.Warning);
-                }
-                return;
-            }
-            if (payload.ValidatorIndex >= context.Validators.Length) return;
-            ConsensusMessage message;
-            try
-            {
-                message = payload.ConsensusMessage;
-            }
-            catch (FormatException)
-            {
-                return;
-            }
-            catch (IOException)
-            {
-                return;
-            }
-            context.LastSeenMessage[payload.ValidatorIndex] = (int)payload.BlockIndex;
-            foreach (IP2PPlugin plugin in Plugin.P2PPlugins)
-                if (!plugin.OnConsensusMessage(payload))
-                    return;
-            switch (message)
-            {
-                case ChangeView view:
-                    OnChangeViewReceived(payload, view);
-                    break;
-                case PrepareRequest request:
-                    OnPrepareRequestReceived(payload, request);
-                    break;
-                case PrepareResponse response:
-                    OnPrepareResponseReceived(payload, response);
-                    break;
-                case Commit commit:
-                    OnCommitReceived(payload, commit);
-                    break;
-                case RecoveryRequest _:
-                    OnRecoveryRequestReceived(payload);
-                    break;
-                case RecoveryMessage recovery:
-                    OnRecoveryMessageReceived(payload, recovery);
-                    break;
-            }
-        }
-
-        private void OnPersistCompleted(Block block)
-        {
-            Log($"persist block: height={block.Index} hash={block.Hash} tx={block.Transactions.Length}");
-            block_received_time = TimeProvider.Current.UtcNow;
-            knownHashes.Clear();
-            InitializeConsensus(0);
-        }
-
-        private void OnRecoveryMessageReceived(ConsensusPayload payload, RecoveryMessage message)
-        {
-            // isRecovering is always set to false again after OnRecoveryMessageReceived
-            isRecovering = true;
-            int validChangeViews = 0, totalChangeViews = 0, validPrepReq = 0, totalPrepReq = 0;
-            int validPrepResponses = 0, totalPrepResponses = 0, validCommits = 0, totalCommits = 0;
-
-            Log($"{nameof(OnRecoveryMessageReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex}");
-            try
-            {
-                if (message.ViewNumber > context.ViewNumber)
-                {
-                    if (context.CommitSent) return;
-                    ConsensusPayload[] changeViewPayloads = message.GetChangeViewPayloads(context, payload);
-                    totalChangeViews = changeViewPayloads.Length;
-                    foreach (ConsensusPayload changeViewPayload in changeViewPayloads)
-                        if (ReverifyAndProcessPayload(changeViewPayload)) validChangeViews++;
-                }
-                if (message.ViewNumber == context.ViewNumber && !context.NotAcceptingPayloadsDueToViewChanging && !context.CommitSent)
-                {
-                    if (!context.RequestSentOrReceived)
-                    {
-                        ConsensusPayload prepareRequestPayload = message.GetPrepareRequestPayload(context, payload);
-                        if (prepareRequestPayload != null)
-                        {
-                            totalPrepReq = 1;
-                            if (ReverifyAndProcessPayload(prepareRequestPayload)) validPrepReq++;
-                        }
-                        else if (context.IsPrimary)
-                            SendPrepareRequest();
-                    }
-                    ConsensusPayload[] prepareResponsePayloads = message.GetPrepareResponsePayloads(context, payload);
-                    totalPrepResponses = prepareResponsePayloads.Length;
-                    foreach (ConsensusPayload prepareResponsePayload in prepareResponsePayloads)
-                        if (ReverifyAndProcessPayload(prepareResponsePayload)) validPrepResponses++;
-                }
-                if (message.ViewNumber <= context.ViewNumber)
-                {
-                    // Ensure we know about all commits from lower view numbers.
-                    ConsensusPayload[] commitPayloads = message.GetCommitPayloadsFromRecoveryMessage(context, payload);
-                    totalCommits = commitPayloads.Length;
-                    foreach (ConsensusPayload commitPayload in commitPayloads)
-                        if (ReverifyAndProcessPayload(commitPayload)) validCommits++;
-                }
-            }
-            finally
-            {
-                Log($"{nameof(OnRecoveryMessageReceived)}: finished (valid/total) " +
-                    $"ChgView: {validChangeViews}/{totalChangeViews} " +
-                    $"PrepReq: {validPrepReq}/{totalPrepReq} " +
-                    $"PrepResp: {validPrepResponses}/{totalPrepResponses} " +
-                    $"Commits: {validCommits}/{totalCommits}");
-                isRecovering = false;
-            }
-        }
-
-        private void OnRecoveryRequestReceived(ConsensusPayload payload)
-        {
-            // We keep track of the payload hashes received in this block, and don't respond with recovery
-            // in response to the same payload that we already responded to previously.
-            // ChangeView messages include a Timestamp when the change view is sent, thus if a node restarts
-            // and issues a change view for the same view, it will have a different hash and will correctly respond
-            // again; however replay attacks of the ChangeView message from arbitrary nodes will not trigger an
-            // additional recovery message response.
-            if (!knownHashes.Add(payload.Hash)) return;
-
-            Log($"On{payload.ConsensusMessage.GetType().Name}Received: height={payload.BlockIndex} index={payload.ValidatorIndex} view={payload.ConsensusMessage.ViewNumber}");
-            if (context.WatchOnly) return;
-            if (!context.CommitSent)
-            {
-                bool shouldSendRecovery = false;
-                int allowedRecoveryNodeCount = context.F;
-                // Limit recoveries to be sent from an upper limit of `f` nodes
-                for (int i = 1; i <= allowedRecoveryNodeCount; i++)
-                {
-                    var chosenIndex = (payload.ValidatorIndex + i) % context.Validators.Length;
-                    if (chosenIndex != context.MyIndex) continue;
-                    shouldSendRecovery = true;
-                    break;
-                }
-
-                if (!shouldSendRecovery) return;
-            }
-            Log($"send recovery: view={context.ViewNumber}");
-            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryMessage() });
-        }
-
-        private void OnPrepareRequestReceived(ConsensusPayload payload, PrepareRequest message)
-        {
-            if (context.RequestSentOrReceived || context.NotAcceptingPayloadsDueToViewChanging) return;
-            if (payload.ValidatorIndex != context.Block.ConsensusData.PrimaryIndex || message.ViewNumber != context.ViewNumber) return;
-            Log($"{nameof(OnPrepareRequestReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex} tx={message.TransactionHashes.Length}");
-            if (message.Timestamp <= context.PrevHeader.Timestamp || message.Timestamp > TimeProvider.Current.UtcNow.AddMinutes(10).ToTimestampMS())
-            {
-                Log($"Timestamp incorrect: {message.Timestamp}", LogLevel.Warning);
-                return;
-            }
-            if (message.TransactionHashes.Any(p => context.Snapshot.ContainsTransaction(p)))
-            {
-                Log($"Invalid request: transaction already exists", LogLevel.Warning);
-                return;
-            }
-
-            // Timeout extension: prepare request has been received with success
-            // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
-            ExtendTimerByFactor(2);
-
-            context.Block.Timestamp = message.Timestamp;
-            context.Block.ConsensusData.Nonce = message.Nonce;
-            context.TransactionHashes = message.TransactionHashes;
-            context.Transactions = new Dictionary<UInt256, Transaction>();
-            for (int i = 0; i < context.PreparationPayloads.Length; i++)
-                if (context.PreparationPayloads[i] != null)
-                    if (!context.PreparationPayloads[i].GetDeserializedMessage<PrepareResponse>().PreparationHash.Equals(payload.Hash))
-                        context.PreparationPayloads[i] = null;
-            context.PreparationPayloads[payload.ValidatorIndex] = payload;
-            byte[] hashData = context.EnsureHeader().GetHashData();
-            for (int i = 0; i < context.CommitPayloads.Length; i++)
-                if (context.CommitPayloads[i]?.ConsensusMessage.ViewNumber == context.ViewNumber)
-                    if (!Crypto.Default.VerifySignature(hashData, context.CommitPayloads[i].GetDeserializedMessage<Commit>().Signature, context.Validators[i].EncodePoint(false)))
-                        context.CommitPayloads[i] = null;
-            Dictionary<UInt256, Transaction> mempoolVerified = Blockchain.Singleton.MemPool.GetVerifiedTransactions().ToDictionary(p => p.Hash);
-            List<Transaction> unverified = new List<Transaction>();
-            foreach (UInt256 hash in context.TransactionHashes)
-            {
-                if (mempoolVerified.TryGetValue(hash, out Transaction tx))
-                {
-                    if (!AddTransaction(tx, false))
-                        return;
-                }
-                else
-                {
-                    if (Blockchain.Singleton.MemPool.TryGetValue(hash, out tx))
-                        unverified.Add(tx);
-                }
-            }
-            foreach (Transaction tx in unverified)
-                if (!AddTransaction(tx, true))
-                    return;
-            if (context.Transactions.Count < context.TransactionHashes.Length)
-            {
-                UInt256[] hashes = context.TransactionHashes.Where(i => !context.Transactions.ContainsKey(i)).ToArray();
-                taskManager.Tell(new TaskManager.RestartTasks
-                {
-                    Payload = InvPayload.Create(InventoryType.TX, hashes)
-                });
-            }
-        }
-
-        private void OnPrepareResponseReceived(ConsensusPayload payload, PrepareResponse message)
-        {
-            if (message.ViewNumber != context.ViewNumber) return;
-            if (context.PreparationPayloads[payload.ValidatorIndex] != null || context.NotAcceptingPayloadsDueToViewChanging) return;
-            if (context.PreparationPayloads[context.Block.ConsensusData.PrimaryIndex] != null && !message.PreparationHash.Equals(context.PreparationPayloads[context.Block.ConsensusData.PrimaryIndex].Hash))
-                return;
-
-            // Timeout extension: prepare response has been received with success
-            // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
-            ExtendTimerByFactor(2);
-
-            Log($"{nameof(OnPrepareResponseReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex}");
-            context.PreparationPayloads[payload.ValidatorIndex] = payload;
-            if (context.WatchOnly || context.CommitSent) return;
-            if (context.RequestSentOrReceived)
-                CheckPreparations();
-        }
-
-        protected override void OnReceive(object message)
-        {
-            if (message is Start options)
-            {
-                if (started) return;
-                OnStart(options);
-            }
-            else
-            {
-                if (!started) return;
-                switch (message)
-                {
-                    case SetViewNumber setView:
-                        InitializeConsensus(setView.ViewNumber);
-                        break;
-                    case Timer timer:
-                        OnTimer(timer);
-                        break;
-                    case ConsensusPayload payload:
-                        OnConsensusPayload(payload);
-                        break;
-                    case Transaction transaction:
-                        OnTransaction(transaction);
-                        break;
-                    case Blockchain.PersistCompleted completed:
-                        OnPersistCompleted(completed.Block);
-                        break;
-                }
-            }
-        }
-
-        private void RequestRecovery()
-        {
-            if (context.Block.Index == Blockchain.Singleton.HeaderHeight + 1)
-                localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryRequest() });
-        }
-
-        private void OnStart(Start options)
-        {
-            Log("OnStart");
-            started = true;
-            if (!options.IgnoreRecoveryLogs && context.Load())
-            {
-                if (context.Transactions != null)
-                {
-                    Sender.Ask<Blockchain.FillCompleted>(new Blockchain.FillMemoryPool
-                    {
-                        Transactions = context.Transactions.Values
-                    }).Wait();
-                }
-                if (context.CommitSent)
-                {
-                    CheckPreparations();
-                    return;
-                }
-            }
-            InitializeConsensus(0);
-            // Issue a ChangeView with NewViewNumber of 0 to request recovery messages on start-up.
-            if (!context.WatchOnly)
-                RequestRecovery();
-        }
-
-        private void OnTimer(Timer timer)
-        {
-            if (context.WatchOnly || context.BlockSent) return;
-            if (timer.Height != context.Block.Index || timer.ViewNumber != context.ViewNumber) return;
-            Log($"timeout: height={timer.Height} view={timer.ViewNumber}");
-            if (context.IsPrimary && !context.RequestSentOrReceived)
-            {
-                SendPrepareRequest();
-            }
-            else if ((context.IsPrimary && context.RequestSentOrReceived) || context.IsBackup)
-            {
-                if (context.CommitSent)
-                {
-                    // Re-send commit periodically by sending recover message in case of a network issue.
-                    Log($"send recovery to resend commit");
-                    localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryMessage() });
-                    ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << 1));
-                }
-                else
-                {
-                    var reason = ChangeViewReason.Timeout;
-
-                    if (context.Block != null && context.TransactionHashes?.Count() > context.Transactions?.Count)
-                    {
-                        reason = ChangeViewReason.TxNotFound;
-                    }
-
-                    RequestChangeView(reason);
-                }
-            }
-        }
-
-        private void OnTransaction(Transaction transaction)
-        {
-            if (!context.IsBackup || context.NotAcceptingPayloadsDueToViewChanging || !context.RequestSentOrReceived || context.ResponseSent || context.BlockSent)
-                return;
-            if (context.Transactions.ContainsKey(transaction.Hash)) return;
-            if (!context.TransactionHashes.Contains(transaction.Hash)) return;
-            AddTransaction(transaction, true);
-        }
-
-        protected override void PostStop()
-        {
-            Log("OnStop");
-            started = false;
-            Context.System.EventStream.Unsubscribe(Self);
-            context.Dispose();
-            base.PostStop();
-        }
-
-        public static Props Props(IActorRef localNode, IActorRef taskManager, Store store, Wallet wallet)
-        {
-            return Akka.Actor.Props.Create(() => new ConsensusService(localNode, taskManager, store, wallet)).WithMailbox("consensus-service-mailbox");
-        }
-
-        private void RequestChangeView(ChangeViewReason reason)
-        {
-            if (context.WatchOnly) return;
-            // Request for next view is always one view more than the current context.ViewNumber
-            // Nodes will not contribute for changing to a view higher than (context.ViewNumber+1), unless they are recovered
-            // The latter may happen by nodes in higher views with, at least, `M` proofs
-            byte expectedView = context.ViewNumber;
-            expectedView++;
-            ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (expectedView + 1)));
-            if ((context.CountCommitted + context.CountFailed) > context.F)
-            {
-                Log($"Skip requesting change view to nv={expectedView} because nc={context.CountCommitted} nf={context.CountFailed}");
-                RequestRecovery();
-                return;
-            }
-            Log($"request change view: height={context.Block.Index} view={context.ViewNumber} nv={expectedView} nc={context.CountCommitted} nf={context.CountFailed}");
-            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeChangeView(reason) });
-            CheckExpectedView(expectedView);
-        }
-
-        private bool ReverifyAndProcessPayload(ConsensusPayload payload)
-        {
-            if (!payload.Verify(context.Snapshot)) return false;
-            OnConsensusPayload(payload);
-            return true;
-        }
-
-        private void SendPrepareRequest()
-        {
-            Log($"send prepare request: height={context.Block.Index} view={context.ViewNumber}");
-            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakePrepareRequest() });
-
-            if (context.Validators.Length == 1)
-                CheckPreparations();
-
-            if (context.TransactionHashes.Length > 0)
-            {
-                foreach (InvPayload payload in InvPayload.CreateGroup(InventoryType.TX, context.TransactionHashes))
-                    localNode.Tell(Message.Create(MessageCommand.Inv, payload));
-            }
-            ChangeTimer(TimeSpan.FromMilliseconds((Blockchain.MillisecondsPerBlock << (context.ViewNumber + 1)) - (context.ViewNumber == 0 ? Blockchain.MillisecondsPerBlock : 0)));
-        }
-    }
-
-    internal class ConsensusServiceMailbox : PriorityMailbox
-    {
-        public ConsensusServiceMailbox(Akka.Actor.Settings settings, Config config)
-            : base(settings, config)
-        {
-        }
-
-        internal protected override bool IsHighPriority(object message)
-        {
-            switch (message)
-            {
-                case ConsensusPayload _:
-                case ConsensusService.SetViewNumber _:
-                case ConsensusService.Timer _:
-                case Blockchain.PersistCompleted _:
-                    return true;
-                default:
-                    return false;
-            }
-        }
-    }
-}
+                }
+
+                // Timeout extension due to prepare response sent
+                // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
+                ExtendTimerByFactor(2);
+
+                Log($"send prepare response");
+                localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakePrepareResponse() });
+                CheckPreparations();
+            }
+            return true;
+        }
+
+        private void ChangeTimer(TimeSpan delay)
+        {
+            clock_started = TimeProvider.Current.UtcNow;
+            expected_delay = delay;
+            timer_token.CancelIfNotNull();
+            timer_token = Context.System.Scheduler.ScheduleTellOnceCancelable(delay, Self, new Timer
+            {
+                Height = context.Block.Index,
+                ViewNumber = context.ViewNumber
+            }, ActorRefs.NoSender);
+        }
+
+        private void CheckCommits()
+        {
+            if (context.CommitPayloads.Count(p => p?.ConsensusMessage.ViewNumber == context.ViewNumber) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
+            {
+                Block block = context.CreateBlock();
+                Log($"relay block: height={block.Index} hash={block.Hash} tx={block.Transactions.Length}");
+                localNode.Tell(new LocalNode.Relay { Inventory = block });
+            }
+        }
+
+        private void CheckExpectedView(byte viewNumber)
+        {
+            if (context.ViewNumber >= viewNumber) return;
+            // if there are `M` change view payloads with NewViewNumber greater than viewNumber, then, it is safe to move
+            if (context.ChangeViewPayloads.Count(p => p != null && p.GetDeserializedMessage<ChangeView>().NewViewNumber >= viewNumber) >= context.M)
+            {
+                if (!context.WatchOnly)
+                {
+                    ChangeView message = context.ChangeViewPayloads[context.MyIndex]?.GetDeserializedMessage<ChangeView>();
+                    // Communicate the network about my agreement to move to `viewNumber`
+                    // if my last change view payload, `message`, has NewViewNumber lower than current view to change
+                    if (message is null || message.NewViewNumber < viewNumber)
+                        localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeChangeView(ChangeViewReason.ChangeAgreement) });
+                }
+                InitializeConsensus(viewNumber);
+            }
+        }
+
+        private void CheckPreparations()
+        {
+            if (context.PreparationPayloads.Count(p => p != null) >= context.M && context.TransactionHashes.All(p => context.Transactions.ContainsKey(p)))
+            {
+                ConsensusPayload payload = context.MakeCommit();
+                Log($"send commit");
+                context.Save();
+                localNode.Tell(new LocalNode.SendDirectly { Inventory = payload });
+                // Set timer, so we will resend the commit in case of a networking issue
+                ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock));
+                CheckCommits();
+            }
+        }
+
+        private void InitializeConsensus(byte viewNumber)
+        {
+            context.Reset(viewNumber);
+            if (viewNumber > 0)
+                Log($"changeview: view={viewNumber} primary={context.Validators[context.GetPrimaryIndex((byte)(viewNumber - 1u))]}", LogLevel.Warning);
+            Log($"initialize: height={context.Block.Index} view={viewNumber} index={context.MyIndex} role={(context.IsPrimary ? "Primary" : context.WatchOnly ? "WatchOnly" : "Backup")}");
+            if (context.WatchOnly) return;
+            if (context.IsPrimary)
+            {
+                if (isRecovering)
+                {
+                    ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (viewNumber + 1)));
+                }
+                else
+                {
+                    TimeSpan span = TimeProvider.Current.UtcNow - block_received_time;
+                    if (span >= Blockchain.TimePerBlock)
+                        ChangeTimer(TimeSpan.Zero);
+                    else
+                        ChangeTimer(Blockchain.TimePerBlock - span);
+                }
+            }
+            else
+            {
+                ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (viewNumber + 1)));
+            }
+        }
+
+        private void Log(string message, LogLevel level = LogLevel.Info)
+        {
+            Console.WriteLine($"[{DateTime.Now.TimeOfDay:hh\\:mm\\:ss\\.fff}] {message}");
+            Plugin.Log(nameof(ConsensusService), level, message);
+        }
+
+        private void OnChangeViewReceived(ConsensusPayload payload, ChangeView message)
+        {
+            if (message.NewViewNumber <= context.ViewNumber)
+                OnRecoveryRequestReceived(payload);
+
+            if (context.CommitSent) return;
+
+            var expectedView = context.ChangeViewPayloads[payload.ValidatorIndex]?.GetDeserializedMessage<ChangeView>().NewViewNumber ?? (byte)0;
+            if (message.NewViewNumber <= expectedView)
+                return;
+
+            Log($"{nameof(OnChangeViewReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex} nv={message.NewViewNumber}");
+            context.ChangeViewPayloads[payload.ValidatorIndex] = payload;
+            CheckExpectedView(message.NewViewNumber);
+        }
+
+        private void OnCommitReceived(ConsensusPayload payload, Commit commit)
+        {
+            ref ConsensusPayload existingCommitPayload = ref context.CommitPayloads[payload.ValidatorIndex];
+            if (existingCommitPayload != null)
+            {
+                if (existingCommitPayload.Hash != payload.Hash)
+                    Log($"{nameof(OnCommitReceived)}: different commit from validator! height={payload.BlockIndex} index={payload.ValidatorIndex} view={commit.ViewNumber} existingView={existingCommitPayload.ConsensusMessage.ViewNumber}", LogLevel.Warning);
+                return;
+            }
+
+            // Timeout extension: commit has been received with success
+            // around 4*15s/M=60.0s/5=12.0s ~ 80% block time (for M=5)
+            ExtendTimerByFactor(4);
+
+            if (commit.ViewNumber == context.ViewNumber)
+            {
+                Log($"{nameof(OnCommitReceived)}: height={payload.BlockIndex} view={commit.ViewNumber} index={payload.ValidatorIndex} nc={context.CountCommitted} nf={context.CountFailed}");
+
+                byte[] hashData = context.EnsureHeader()?.GetHashData();
+                if (hashData == null)
+                {
+                    existingCommitPayload = payload;
+                }
+                else if (Crypto.Default.VerifySignature(hashData, commit.Signature,
+                    context.Validators[payload.ValidatorIndex].EncodePoint(false)))
+                {
+                    existingCommitPayload = payload;
+                    CheckCommits();
+                }
+                return;
+            }
+            // Receiving commit from another view
+            Log($"{nameof(OnCommitReceived)}: record commit for different view={commit.ViewNumber} index={payload.ValidatorIndex} height={payload.BlockIndex}");
+            existingCommitPayload = payload;
+        }
+
+        // this function increases existing timer (never decreases) with a value proportional to `maxDelayInBlockTimes`*`Blockchain.MillisecondsPerBlock`
+        private void ExtendTimerByFactor(int maxDelayInBlockTimes)
+        {
+            TimeSpan nextDelay = expected_delay - (TimeProvider.Current.UtcNow - clock_started) + TimeSpan.FromMilliseconds(maxDelayInBlockTimes * Blockchain.MillisecondsPerBlock / context.M);
+            if (!context.WatchOnly && !context.ViewChanging && !context.CommitSent && (nextDelay > TimeSpan.Zero))
+                ChangeTimer(nextDelay);
+        }
+
+        private void OnConsensusPayload(ConsensusPayload payload)
+        {
+            if (context.BlockSent) return;
+            if (payload.Version != context.Block.Version) return;
+            if (payload.PrevHash != context.Block.PrevHash || payload.BlockIndex != context.Block.Index)
+            {
+                if (context.Block.Index < payload.BlockIndex)
+                {
+                    Log($"chain sync: expected={payload.BlockIndex} current={context.Block.Index - 1} nodes={LocalNode.Singleton.ConnectedCount}", LogLevel.Warning);
+                }
+                return;
+            }
+            if (payload.ValidatorIndex >= context.Validators.Length) return;
+            ConsensusMessage message;
+            try
+            {
+                message = payload.ConsensusMessage;
+            }
+            catch (FormatException)
+            {
+                return;
+            }
+            catch (IOException)
+            {
+                return;
+            }
+            context.LastSeenMessage[payload.ValidatorIndex] = (int)payload.BlockIndex;
+            foreach (IP2PPlugin plugin in Plugin.P2PPlugins)
+                if (!plugin.OnConsensusMessage(payload))
+                    return;
+            switch (message)
+            {
+                case ChangeView view:
+                    OnChangeViewReceived(payload, view);
+                    break;
+                case PrepareRequest request:
+                    OnPrepareRequestReceived(payload, request);
+                    break;
+                case PrepareResponse response:
+                    OnPrepareResponseReceived(payload, response);
+                    break;
+                case Commit commit:
+                    OnCommitReceived(payload, commit);
+                    break;
+                case RecoveryRequest _:
+                    OnRecoveryRequestReceived(payload);
+                    break;
+                case RecoveryMessage recovery:
+                    OnRecoveryMessageReceived(payload, recovery);
+                    break;
+            }
+        }
+
+        private void OnPersistCompleted(Block block)
+        {
+            Log($"persist block: height={block.Index} hash={block.Hash} tx={block.Transactions.Length}");
+            block_received_time = TimeProvider.Current.UtcNow;
+            knownHashes.Clear();
+            InitializeConsensus(0);
+        }
+
+        private void OnRecoveryMessageReceived(ConsensusPayload payload, RecoveryMessage message)
+        {
+            // isRecovering is always set to false again after OnRecoveryMessageReceived
+            isRecovering = true;
+            int validChangeViews = 0, totalChangeViews = 0, validPrepReq = 0, totalPrepReq = 0;
+            int validPrepResponses = 0, totalPrepResponses = 0, validCommits = 0, totalCommits = 0;
+
+            Log($"{nameof(OnRecoveryMessageReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex}");
+            try
+            {
+                if (message.ViewNumber > context.ViewNumber)
+                {
+                    if (context.CommitSent) return;
+                    ConsensusPayload[] changeViewPayloads = message.GetChangeViewPayloads(context, payload);
+                    totalChangeViews = changeViewPayloads.Length;
+                    foreach (ConsensusPayload changeViewPayload in changeViewPayloads)
+                        if (ReverifyAndProcessPayload(changeViewPayload)) validChangeViews++;
+                }
+                if (message.ViewNumber == context.ViewNumber && !context.NotAcceptingPayloadsDueToViewChanging && !context.CommitSent)
+                {
+                    if (!context.RequestSentOrReceived)
+                    {
+                        ConsensusPayload prepareRequestPayload = message.GetPrepareRequestPayload(context, payload);
+                        if (prepareRequestPayload != null)
+                        {
+                            totalPrepReq = 1;
+                            if (ReverifyAndProcessPayload(prepareRequestPayload)) validPrepReq++;
+                        }
+                        else if (context.IsPrimary)
+                            SendPrepareRequest();
+                    }
+                    ConsensusPayload[] prepareResponsePayloads = message.GetPrepareResponsePayloads(context, payload);
+                    totalPrepResponses = prepareResponsePayloads.Length;
+                    foreach (ConsensusPayload prepareResponsePayload in prepareResponsePayloads)
+                        if (ReverifyAndProcessPayload(prepareResponsePayload)) validPrepResponses++;
+                }
+                if (message.ViewNumber <= context.ViewNumber)
+                {
+                    // Ensure we know about all commits from lower view numbers.
+                    ConsensusPayload[] commitPayloads = message.GetCommitPayloadsFromRecoveryMessage(context, payload);
+                    totalCommits = commitPayloads.Length;
+                    foreach (ConsensusPayload commitPayload in commitPayloads)
+                        if (ReverifyAndProcessPayload(commitPayload)) validCommits++;
+                }
+            }
+            finally
+            {
+                Log($"{nameof(OnRecoveryMessageReceived)}: finished (valid/total) " +
+                    $"ChgView: {validChangeViews}/{totalChangeViews} " +
+                    $"PrepReq: {validPrepReq}/{totalPrepReq} " +
+                    $"PrepResp: {validPrepResponses}/{totalPrepResponses} " +
+                    $"Commits: {validCommits}/{totalCommits}");
+                isRecovering = false;
+            }
+        }
+
+        private void OnRecoveryRequestReceived(ConsensusPayload payload)
+        {
+            // We keep track of the payload hashes received in this block, and don't respond with recovery
+            // in response to the same payload that we already responded to previously.
+            // ChangeView messages include a Timestamp when the change view is sent, thus if a node restarts
+            // and issues a change view for the same view, it will have a different hash and will correctly respond
+            // again; however replay attacks of the ChangeView message from arbitrary nodes will not trigger an
+            // additional recovery message response.
+            if (!knownHashes.Add(payload.Hash)) return;
+
+            Log($"On{payload.ConsensusMessage.GetType().Name}Received: height={payload.BlockIndex} index={payload.ValidatorIndex} view={payload.ConsensusMessage.ViewNumber}");
+            if (context.WatchOnly) return;
+            if (!context.CommitSent)
+            {
+                bool shouldSendRecovery = false;
+                int allowedRecoveryNodeCount = context.F;
+                // Limit recoveries to be sent from an upper limit of `f` nodes
+                for (int i = 1; i <= allowedRecoveryNodeCount; i++)
+                {
+                    var chosenIndex = (payload.ValidatorIndex + i) % context.Validators.Length;
+                    if (chosenIndex != context.MyIndex) continue;
+                    shouldSendRecovery = true;
+                    break;
+                }
+
+                if (!shouldSendRecovery) return;
+            }
+            Log($"send recovery: view={context.ViewNumber}");
+            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryMessage() });
+        }
+
+        private void OnPrepareRequestReceived(ConsensusPayload payload, PrepareRequest message)
+        {
+            if (context.RequestSentOrReceived || context.NotAcceptingPayloadsDueToViewChanging) return;
+            if (payload.ValidatorIndex != context.Block.ConsensusData.PrimaryIndex || message.ViewNumber != context.ViewNumber) return;
+            Log($"{nameof(OnPrepareRequestReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex} tx={message.TransactionHashes.Length}");
+            if (message.Timestamp <= context.PrevHeader.Timestamp || message.Timestamp > TimeProvider.Current.UtcNow.AddMinutes(10).ToTimestampMS())
+            {
+                Log($"Timestamp incorrect: {message.Timestamp}", LogLevel.Warning);
+                return;
+            }
+            if (message.TransactionHashes.Any(p => context.Snapshot.ContainsTransaction(p)))
+            {
+                Log($"Invalid request: transaction already exists", LogLevel.Warning);
+                return;
+            }
+
+            // Timeout extension: prepare request has been received with success
+            // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
+            ExtendTimerByFactor(2);
+
+            context.Block.Timestamp = message.Timestamp;
+            context.Block.ConsensusData.Nonce = message.Nonce;
+            context.TransactionHashes = message.TransactionHashes;
+            context.Transactions = new Dictionary<UInt256, Transaction>();
+            for (int i = 0; i < context.PreparationPayloads.Length; i++)
+                if (context.PreparationPayloads[i] != null)
+                    if (!context.PreparationPayloads[i].GetDeserializedMessage<PrepareResponse>().PreparationHash.Equals(payload.Hash))
+                        context.PreparationPayloads[i] = null;
+            context.PreparationPayloads[payload.ValidatorIndex] = payload;
+            byte[] hashData = context.EnsureHeader().GetHashData();
+            for (int i = 0; i < context.CommitPayloads.Length; i++)
+                if (context.CommitPayloads[i]?.ConsensusMessage.ViewNumber == context.ViewNumber)
+                    if (!Crypto.Default.VerifySignature(hashData, context.CommitPayloads[i].GetDeserializedMessage<Commit>().Signature, context.Validators[i].EncodePoint(false)))
+                        context.CommitPayloads[i] = null;
+            Dictionary<UInt256, Transaction> mempoolVerified = Blockchain.Singleton.MemPool.GetVerifiedTransactions().ToDictionary(p => p.Hash);
+            List<Transaction> unverified = new List<Transaction>();
+            foreach (UInt256 hash in context.TransactionHashes)
+            {
+                if (mempoolVerified.TryGetValue(hash, out Transaction tx))
+                {
+                    if (!AddTransaction(tx, false))
+                        return;
+                }
+                else
+                {
+                    if (Blockchain.Singleton.MemPool.TryGetValue(hash, out tx))
+                        unverified.Add(tx);
+                }
+            }
+            foreach (Transaction tx in unverified)
+                if (!AddTransaction(tx, true))
+                    return;
+            if (context.Transactions.Count < context.TransactionHashes.Length)
+            {
+                UInt256[] hashes = context.TransactionHashes.Where(i => !context.Transactions.ContainsKey(i)).ToArray();
+                taskManager.Tell(new TaskManager.RestartTasks
+                {
+                    Payload = InvPayload.Create(InventoryType.TX, hashes)
+                });
+            }
+        }
+
+        private void OnPrepareResponseReceived(ConsensusPayload payload, PrepareResponse message)
+        {
+            if (message.ViewNumber != context.ViewNumber) return;
+            if (context.PreparationPayloads[payload.ValidatorIndex] != null || context.NotAcceptingPayloadsDueToViewChanging) return;
+            if (context.PreparationPayloads[context.Block.ConsensusData.PrimaryIndex] != null && !message.PreparationHash.Equals(context.PreparationPayloads[context.Block.ConsensusData.PrimaryIndex].Hash))
+                return;
+
+            // Timeout extension: prepare response has been received with success
+            // around 2*15/M=30.0/5 ~ 40% block time (for M=5)
+            ExtendTimerByFactor(2);
+
+            Log($"{nameof(OnPrepareResponseReceived)}: height={payload.BlockIndex} view={message.ViewNumber} index={payload.ValidatorIndex}");
+            context.PreparationPayloads[payload.ValidatorIndex] = payload;
+            if (context.WatchOnly || context.CommitSent) return;
+            if (context.RequestSentOrReceived)
+                CheckPreparations();
+        }
+
+        protected override void OnReceive(object message)
+        {
+            if (message is Start options)
+            {
+                if (started) return;
+                OnStart(options);
+            }
+            else
+            {
+                if (!started) return;
+                switch (message)
+                {
+                    case SetViewNumber setView:
+                        InitializeConsensus(setView.ViewNumber);
+                        break;
+                    case Timer timer:
+                        OnTimer(timer);
+                        break;
+                    case ConsensusPayload payload:
+                        OnConsensusPayload(payload);
+                        break;
+                    case Transaction transaction:
+                        OnTransaction(transaction);
+                        break;
+                    case Blockchain.PersistCompleted completed:
+                        OnPersistCompleted(completed.Block);
+                        break;
+                }
+            }
+        }
+
+        private void RequestRecovery()
+        {
+            if (context.Block.Index == Blockchain.Singleton.HeaderHeight + 1)
+                localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryRequest() });
+        }
+
+        private void OnStart(Start options)
+        {
+            Log("OnStart");
+            started = true;
+            if (!options.IgnoreRecoveryLogs && context.Load())
+            {
+                if (context.Transactions != null)
+                {
+                    Sender.Ask<Blockchain.FillCompleted>(new Blockchain.FillMemoryPool
+                    {
+                        Transactions = context.Transactions.Values
+                    }).Wait();
+                }
+                if (context.CommitSent)
+                {
+                    CheckPreparations();
+                    return;
+                }
+            }
+            InitializeConsensus(0);
+            // Issue a ChangeView with NewViewNumber of 0 to request recovery messages on start-up.
+            if (!context.WatchOnly)
+                RequestRecovery();
+        }
+
+        private void OnTimer(Timer timer)
+        {
+            if (context.WatchOnly || context.BlockSent) return;
+            if (timer.Height != context.Block.Index || timer.ViewNumber != context.ViewNumber) return;
+            Log($"timeout: height={timer.Height} view={timer.ViewNumber}");
+            if (context.IsPrimary && !context.RequestSentOrReceived)
+            {
+                SendPrepareRequest();
+            }
+            else if ((context.IsPrimary && context.RequestSentOrReceived) || context.IsBackup)
+            {
+                if (context.CommitSent)
+                {
+                    // Re-send commit periodically by sending recover message in case of a network issue.
+                    Log($"send recovery to resend commit");
+                    localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeRecoveryMessage() });
+                    ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << 1));
+                }
+                else
+                {
+                    var reason = ChangeViewReason.Timeout;
+
+                    if (context.Block != null && context.TransactionHashes?.Count() > context.Transactions?.Count)
+                    {
+                        reason = ChangeViewReason.TxNotFound;
+                    }
+
+                    RequestChangeView(reason);
+                }
+            }
+        }
+
+        private void OnTransaction(Transaction transaction)
+        {
+            if (!context.IsBackup || context.NotAcceptingPayloadsDueToViewChanging || !context.RequestSentOrReceived || context.ResponseSent || context.BlockSent)
+                return;
+            if (context.Transactions.ContainsKey(transaction.Hash)) return;
+            if (!context.TransactionHashes.Contains(transaction.Hash)) return;
+            AddTransaction(transaction, true);
+        }
+
+        protected override void PostStop()
+        {
+            Log("OnStop");
+            started = false;
+            Context.System.EventStream.Unsubscribe(Self);
+            context.Dispose();
+            base.PostStop();
+        }
+
+        public static Props Props(IActorRef localNode, IActorRef taskManager, Store store, Wallet wallet)
+        {
+            return Akka.Actor.Props.Create(() => new ConsensusService(localNode, taskManager, store, wallet)).WithMailbox("consensus-service-mailbox");
+        }
+
+        private void RequestChangeView(ChangeViewReason reason)
+        {
+            if (context.WatchOnly) return;
+            // Request for next view is always one view more than the current context.ViewNumber
+            // Nodes will not contribute for changing to a view higher than (context.ViewNumber+1), unless they are recovered
+            // The latter may happen by nodes in higher views with, at least, `M` proofs
+            byte expectedView = context.ViewNumber;
+            expectedView++;
+            ChangeTimer(TimeSpan.FromMilliseconds(Blockchain.MillisecondsPerBlock << (expectedView + 1)));
+            if ((context.CountCommitted + context.CountFailed) > context.F)
+            {
+                Log($"Skip requesting change view to nv={expectedView} because nc={context.CountCommitted} nf={context.CountFailed}");
+                RequestRecovery();
+                return;
+            }
+            Log($"request change view: height={context.Block.Index} view={context.ViewNumber} nv={expectedView} nc={context.CountCommitted} nf={context.CountFailed}");
+            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakeChangeView(reason) });
+            CheckExpectedView(expectedView);
+        }
+
+        private bool ReverifyAndProcessPayload(ConsensusPayload payload)
+        {
+            if (!payload.Verify(context.Snapshot)) return false;
+            OnConsensusPayload(payload);
+            return true;
+        }
+
+        private void SendPrepareRequest()
+        {
+            Log($"send prepare request: height={context.Block.Index} view={context.ViewNumber}");
+            localNode.Tell(new LocalNode.SendDirectly { Inventory = context.MakePrepareRequest() });
+
+            if (context.Validators.Length == 1)
+                CheckPreparations();
+
+            if (context.TransactionHashes.Length > 0)
+            {
+                foreach (InvPayload payload in InvPayload.CreateGroup(InventoryType.TX, context.TransactionHashes))
+                    localNode.Tell(Message.Create(MessageCommand.Inv, payload));
+            }
+            ChangeTimer(TimeSpan.FromMilliseconds((Blockchain.MillisecondsPerBlock << (context.ViewNumber + 1)) - (context.ViewNumber == 0 ? Blockchain.MillisecondsPerBlock : 0)));
+        }
+    }
+
+    internal class ConsensusServiceMailbox : PriorityMailbox
+    {
+        public ConsensusServiceMailbox(Akka.Actor.Settings settings, Config config)
+            : base(settings, config)
+        {
+        }
+
+        internal protected override bool IsHighPriority(object message)
+        {
+            switch (message)
+            {
+                case ConsensusPayload _:
+                case ConsensusService.SetViewNumber _:
+                case ConsensusService.Timer _:
+                case Blockchain.PersistCompleted _:
+                    return true;
+                default:
+                    return false;
+            }
+        }
+    }
+}