diff --git a/TLSharp.Core/Auth/Authenticator.cs b/TLSharp.Core/Auth/Authenticator.cs
index c56dffc..1342555 100644
--- a/TLSharp.Core/Auth/Authenticator.cs
+++ b/TLSharp.Core/Auth/Authenticator.cs
@@ -6,7 +6,7 @@ namespace TLSharp.Core.Auth
 {
     public static class Authenticator
     {
-        public static async Task<Step3_Response> DoAuthentication(TcpTransport transport, CancellationToken token)
+        public static async Task<Step3_Response> DoAuthentication(TcpTransport transport, CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();
             
diff --git a/TLSharp.Core/Network/MtProtoPlainSender.cs b/TLSharp.Core/Network/MtProtoPlainSender.cs
index e468084..bace652 100644
--- a/TLSharp.Core/Network/MtProtoPlainSender.cs
+++ b/TLSharp.Core/Network/MtProtoPlainSender.cs
@@ -18,7 +18,7 @@ namespace TLSharp.Core.Network
             _random = new Random();
         }
 
-        public async Task Send(byte[] data, CancellationToken token)
+        public async Task Send(byte[] data, CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();
 
@@ -38,7 +38,7 @@ namespace TLSharp.Core.Network
             }
         }
 
-        public async Task<byte[]> Receive(CancellationToken token)
+        public async Task<byte[]> Receive(CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();
 
diff --git a/TLSharp.Core/Network/MtProtoSender.cs b/TLSharp.Core/Network/MtProtoSender.cs
index ff412e1..71e2bc9 100644
--- a/TLSharp.Core/Network/MtProtoSender.cs
+++ b/TLSharp.Core/Network/MtProtoSender.cs
@@ -33,7 +33,7 @@ namespace TLSharp.Core.Network
             return confirmed ? _session.Sequence++ * 2 + 1 : _session.Sequence * 2;
         }
 
-        public async Task Send(TeleSharp.TL.TLMethod request, CancellationToken token)
+        public async Task Send(TeleSharp.TL.TLMethod request, CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();
 
@@ -61,7 +61,7 @@ namespace TLSharp.Core.Network
             _session.Save();
         }
 
-        public async Task Send(byte[] packet, TeleSharp.TL.TLMethod request, CancellationToken token)
+        public async Task Send(byte[] packet, TeleSharp.TL.TLMethod request, CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();
             
@@ -130,7 +130,7 @@ namespace TLSharp.Core.Network
             return new Tuple<byte[], ulong, int>(message, remoteMessageId, remoteSequence);
         }
 
-        public async Task<byte[]> Receive(TeleSharp.TL.TLMethod request, CancellationToken token)
+        public async Task<byte[]> Receive(TeleSharp.TL.TLMethod request, CancellationToken token = default(CancellationToken))
         {
             while (!request.ConfirmReceived)
             {
@@ -148,7 +148,7 @@ namespace TLSharp.Core.Network
             return null;
         }
 
-        public async Task SendPingAsync(CancellationToken token)
+        public async Task SendPingAsync(CancellationToken token = default(CancellationToken))
         {
             token.ThrowIfCancellationRequested();