diff --git a/Unity/SiteServer.cs b/Unity/SiteServer.cs
index d1f4236..4dde64b 100644
--- a/Unity/SiteServer.cs
+++ b/Unity/SiteServer.cs
@@ -18,7 +18,8 @@ namespace RoboidControl.Unity {
         }
 
         void OnApplicationQuit() {
-            site.Close();
+            if (site != null)
+                site.Close();
         }
 
         public void HandleNewThing(RoboidControl.Thing thing) {
diff --git a/Unity/Thing.cs b/Unity/Thing.cs
index 98551fe..129f34b 100644
--- a/Unity/Thing.cs
+++ b/Unity/Thing.cs
@@ -31,7 +31,7 @@ namespace RoboidControl.Unity {
             core.component = this;
 
             SiteServer siteServer = FindAnyObjectByType<SiteServer>();
-            if (siteServer == null) {
+            if (siteServer == null || siteServer.site == null) {
                 Debug.LogWarning("No site server found");
                 return;
             }
@@ -93,7 +93,7 @@ namespace RoboidControl.Unity {
         }
 
         private void PoseChanged() {
-            Debug.Log($"{this} pose changed");
+            // Debug.Log($"{this} pose changed");
             if (core.positionUpdated)
                 this.transform.localPosition = core.position.ToVector3();
             if (core.orientationUpdated)
diff --git a/src/Messages/BinaryMsg.cs b/src/Messages/BinaryMsg.cs
index 6953188..408ba94 100644
--- a/src/Messages/BinaryMsg.cs
+++ b/src/Messages/BinaryMsg.cs
@@ -12,7 +12,7 @@ namespace RoboidControl {
         /// The length of the message, excluding the binary data
         /// </summary>
         /// For the total size of the message this.bytes.Length should be added to this value.
-        public const byte length = 2;
+        public const byte length = 4;
         /// <summary>
         /// The network ID identifying the thing
         /// </summary>
@@ -23,23 +23,15 @@ namespace RoboidControl {
         public byte thingId;
         
         public Thing thing;        
-
+        /// <summary>
+        /// The length of the data
+        /// </summary>
+        public byte dataLength;
         /// <summary>
         /// The binary data
         /// </summary>
-        public byte[] bytes;
+        public byte[] data;
 
-        /// <summary>
-        /// Create a new message for sending
-        /// </summary>
-        /// <param name="networkId">The netowork ID of the thing</param>
-        /// <param name="thingId">The ID of the thing</param>
-        /// <param name="bytes">The binary data for the thing</param>
-        public BinaryMsg(byte networkId, byte thingId, byte[] bytes) : base() {
-            this.networkId = networkId;
-            this.thingId = thingId;
-            this.bytes = bytes;
-        }
         /// <summary>
         /// Create an empty message for sending
         /// </summary>
@@ -49,31 +41,32 @@ namespace RoboidControl {
             this.networkId = networkId;
             this.thingId = thing.id;
             this.thing = thing;
-            this.bytes = this.thing.GenerateBinary();
-            // if (this.bytes.Length > 0)
-            //     System.Console.Write($"Binary message for [{networkId}/{thing.id}]");
+            this.data = this.thing.GenerateBinary();
+            this.dataLength = (byte)this.data.Length;
         }
         /// @copydoc Passer::RoboidControl::IMessage::IMessage(byte[] buffer)
         public BinaryMsg(byte[] buffer) {
             byte ix = 1;
             this.networkId = buffer[ix++];
             this.thingId = buffer[ix++];
-            byte length = (byte)(buffer.Length - ix);
-            this.bytes = new byte[length];
-            for (uint bytesIx = 0; bytesIx < length; bytesIx++)
-                this.bytes[bytesIx] = buffer[ix++];
+            this.dataLength = buffer[ix++];
+            this.data = new byte[this.dataLength];
+            for (uint dataIx = 0; dataIx < this.dataLength; dataIx++)
+                this.data[dataIx] = buffer[ix++];
         }
 
         /// @copydoc Passer::RoboidControl::IMessage::Serialize
         public override byte Serialize(ref byte[] buffer) {            
-            if (buffer.Length < BinaryMsg.length + this.bytes.Length || this.bytes.Length == 0)
+            if (buffer.Length < BinaryMsg.length + this.data.Length || this.data.Length == 0)
                 return 0;
-                
+            
+            System.Console.Write($"sending Binary [{this.networkId}/{this.thingId}]");
             byte ix = 0;
             buffer[ix++] = BinaryMsg.Id;
             buffer[ix++] = this.networkId;
             buffer[ix++] = this.thingId;
-            foreach (byte b in bytes)
+            buffer[ix++] = this.dataLength;
+            foreach (byte b in data)
                 buffer[ix++] = b;
 
             return ix;
diff --git a/src/Messages/ModelUrlMsg.cs b/src/Messages/ModelUrlMsg.cs
index be15087..3a2d3fc 100644
--- a/src/Messages/ModelUrlMsg.cs
+++ b/src/Messages/ModelUrlMsg.cs
@@ -58,7 +58,7 @@ namespace RoboidControl {
 
         /// @copydoc Passer::RoboidControl::IMessage::Serialize
         public override byte Serialize(ref byte[] buffer) {
-            if (this.url == null)
+            if (string.IsNullOrEmpty(this.url))
                 return 0;
 
             byte ix = 0;
diff --git a/src/Messages/NameMsg.cs b/src/Messages/NameMsg.cs
index 632540f..c1b5faa 100644
--- a/src/Messages/NameMsg.cs
+++ b/src/Messages/NameMsg.cs
@@ -20,10 +20,11 @@ namespace RoboidControl {
         /// The ID of the thing
         /// </summary>
         public byte thingId;
+
         /// <summary>
         /// The length of the name, excluding null terminator
         /// </summary>
-        public byte len;
+        public byte nameLength;
         /// <summary>
         /// The name of the thing, not terminated with a null character
         /// </summary>
@@ -38,6 +39,7 @@ namespace RoboidControl {
             this.networkId = networkId;
             this.thingId = thing.id;
             this.name = thing.name;
+            this.nameLength = (byte)this.name.Length;
         }
         /// <summary>
         /// Create a new message for sending
@@ -45,34 +47,31 @@ namespace RoboidControl {
         /// <param name="networkId">The network ID of the thing</param>
         /// <param name="thingId">The ID of the thing</param>
         /// <param name="name">The name of the thing</param>
-        public NameMsg(byte networkId, byte thingId, string name) {
-            this.networkId = networkId;
-            this.thingId = thingId;
-            this.name = name;
-        }
+        // public NameMsg(byte networkId, byte thingId, string name) {
+        //     this.networkId = networkId;
+        //     this.thingId = thingId;
+        //     this.name = name;
+        // }
         /// @copydoc Passer::RoboidControl::IMessage::IMessage(byte[] buffer)
         public NameMsg(byte[] buffer) {
             byte ix = 1;
             this.networkId = buffer[ix++];
             this.thingId = buffer[ix++];
-            int strlen = buffer[ix++];
-            this.name = System.Text.Encoding.UTF8.GetString(buffer, (int)ix, strlen);
+            this.nameLength = buffer[ix++];
+            this.name = System.Text.Encoding.UTF8.GetString(buffer, (int)ix, this.nameLength);
         }
 
         /// @copydoc Passer::RoboidControl::IMessage::Serialize
         public override byte Serialize(ref byte[] buffer) {
-            if (buffer.Length < NameMsg.length + this.name.Length || this.name.Length == 0)
+            if (buffer.Length < NameMsg.length + this.name.Length || string.IsNullOrEmpty(this.name))
                 return 0;
 
             byte ix = 0;
             buffer[ix++] = NameMsg.Id;
             buffer[ix++] = this.networkId;
             buffer[ix++] = this.thingId;
-
-            int nameLength = this.name.Length;
-
-            buffer[ix++] = (byte)nameLength;
-            for (int nameIx = 0; nameIx < nameLength; nameIx++)
+            buffer[ix++] = this.nameLength;
+            for (int nameIx = 0; nameIx < this.nameLength; nameIx++)
                 buffer[ix++] = (byte)this.name[nameIx];
 
             return ix;
diff --git a/src/Messages/ThingMsg.cs b/src/Messages/ThingMsg.cs
index 2eeae36..9725e23 100644
--- a/src/Messages/ThingMsg.cs
+++ b/src/Messages/ThingMsg.cs
@@ -35,7 +35,6 @@ namespace RoboidControl {
         /// <param name="networkId">The network ID of the thing</param>
         /// <param name="thing">The thing</param>
         public ThingMsg(byte networkId, Thing thing) {
-            System.Console.Write($"ThingMsg [{networkId}/{thing.id}] {thing.type}");
             this.networkId = networkId;
             this.thingId = thing.id;
             this.thingType = thing.type;
@@ -84,7 +83,6 @@ namespace RoboidControl {
             buffer[ix++] = this.thingId;
             buffer[ix++] = this.thingType;
             buffer[ix++] = this.parentId;
-            System.Console.Write("ThingMsg sent");
             return ThingMsg.length;
         }
     }
diff --git a/src/ParticipantUDP.cs b/src/ParticipantUDP.cs
index 3065e62..9021123 100644
--- a/src/ParticipantUDP.cs
+++ b/src/ParticipantUDP.cs
@@ -176,7 +176,7 @@ namespace RoboidControl {
         #region Send
 
         public void SendThingInfo(Participant owner, Thing thing) {
-            Console.WriteLine("Send thing info");
+            // Console.WriteLine("Send thing info");
             this.Send(owner, new ThingMsg(this.networkId, thing));
             this.Send(owner, new NameMsg(this.networkId, thing));
             this.Send(owner, new ModelUrlMsg(this.networkId, thing));
@@ -195,7 +195,7 @@ namespace RoboidControl {
         }
 
         public void PublishThingInfo(Thing thing) {
-            Console.WriteLine("Publish thing info");
+            // Console.WriteLine("Publish thing info");
             this.Publish(new ThingMsg(this.networkId, thing));
             this.Publish(new NameMsg(this.networkId, thing));
             this.Publish(new ModelUrlMsg(this.networkId, thing));
@@ -207,7 +207,7 @@ namespace RoboidControl {
             if (bufferSize <= 0)
                 return true;
 
-            // Console.WriteLine($"publish to {broadcastIpAddress.ToString()} {this.port}");
+            Console.WriteLine($"publish to {broadcastIpAddress.ToString()} {this.port}");
             this.udpClient?.Send(this.buffer, bufferSize, this.broadcastIpAddress, this.port);
             return true;
         }
@@ -234,38 +234,39 @@ namespace RoboidControl {
 
         #region Receive
 
-        public void ReceiveData(byte[] data, Participant remoteParticipant) {
+        public void ReceiveData(byte[] data, Participant sender) {
             byte msgId = data[0];
             if (msgId == 0xFF) {
                 // Timeout
                 return;
             }
 
+            System.Console.Write($"Receive msg {msgId}");
             switch (msgId) {
                 case ParticipantMsg.Id: // 0xA0 / 160
-                    this.Process(remoteParticipant, new ParticipantMsg(data));
+                    this.Process(sender, new ParticipantMsg(data));
                     break;
                 case NetworkIdMsg.Id: // 0xA1 / 161
-                    this.Process(remoteParticipant, new NetworkIdMsg(data));
+                    this.Process(sender, new NetworkIdMsg(data));
                     break;
                 case InvestigateMsg.Id: // 0x81
                     // result = await InvestigateMsg.Receive(dataStream, client, packetSize);
                     break;
                 case ThingMsg.id: // 0x80 / 128
-                    this.Process(remoteParticipant, new ThingMsg(data));
+                    this.Process(sender, new ThingMsg(data));
                     break;
                 case NameMsg.Id: // 0x91 / 145
-                    this.Process(remoteParticipant, new NameMsg(data));
+                    this.Process(sender, new NameMsg(data));
                     break;
                 case ModelUrlMsg.Id: // 0x90 / 144
-                    this.Process(remoteParticipant, new ModelUrlMsg(data));
+                    this.Process(sender, new ModelUrlMsg(data));
                     break;
                 case PoseMsg.Id: // 0x10 / 16
-                    this.Process(remoteParticipant, new PoseMsg(data));
+                    this.Process(sender, new PoseMsg(data));
                     // result = await PoseMsg.Receive(dataStream, client, packetSize);
                     break;
                 case BinaryMsg.Id: // 0xB1 / 177
-                    this.Process(remoteParticipant, new BinaryMsg(data));
+                    this.Process(sender, new BinaryMsg(data));
                     break;
                 case TextMsg.Id: // 0xB0 / 176
                     // result = await TextMsg.Receive(dataStream, client, packetSize);
@@ -316,17 +317,13 @@ namespace RoboidControl {
         }
 
         protected virtual void Process(Participant sender, PoseMsg msg) {
-            Console.WriteLine($"Participant: Process pose [{msg.networkId}/{msg.thingId}] {msg.poseType}");
+            // Console.WriteLine($"Participant: Process pose [{msg.networkId}/{msg.thingId}] {msg.poseType}");
             Thing thing = sender.Get(msg.networkId, msg.thingId);
             if (thing != null) {
-                if ((msg.poseType & PoseMsg.Pose_Position) != 0) {
-                    thing.position = msg.position;
-                    Console.Write($"{thing.id} position changed");
-                }
-                if ((msg.poseType & PoseMsg.Pose_Orientation) != 0) {
-                    thing.orientation = msg.orientation;
-                    Console.Write($"{thing.id} orientation changed");
-                }
+                if ((msg.poseType & PoseMsg.Pose_Position) != 0)
+                    thing.position = msg.position;                
+                if ((msg.poseType & PoseMsg.Pose_Orientation) != 0)
+                    thing.orientation = msg.orientation;                
                 if ((msg.poseType & PoseMsg.Pose_LinearVelocity) != 0)
                     thing.linearVelocity = msg.linearVelocity;
                 if ((msg.poseType & PoseMsg.Pose_AngularVelocity) != 0)
@@ -335,9 +332,9 @@ namespace RoboidControl {
         }
 
         protected virtual void Process(Participant sender, BinaryMsg msg) {
-            // Console.WriteLine($"Participant: Process binary [{msg.networkId}/{msg.thingId}]");
+            Console.WriteLine($"Participant: Process binary [{msg.networkId}/{msg.thingId}]");
             Thing thing = sender.Get(msg.networkId, msg.thingId);
-            thing?.ProcessBinary(msg.bytes);
+            thing?.ProcessBinary(msg.data);
         }
 
         protected virtual void Process(Participant sender, TextMsg temsgxt) { }
diff --git a/src/Thing.cs b/src/Thing.cs
index c1e79ec..00a2020 100644
--- a/src/Thing.cs
+++ b/src/Thing.cs
@@ -49,7 +49,8 @@ namespace RoboidControl {
         public Thing(Participant owner, byte thingType = (byte)Type.Undetermined, bool invokeEvent = true) {
             this.owner = owner;
             this.type = thingType;
-            this.owner.Add(this);
+            if (this.owner != null)
+                this.owner.Add(this);
             if (invokeEvent)
                 InvokeNewThing(this);
         }