diff --git a/.gitignore b/.gitignore
index 20526e9..dd49250 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,7 @@ UserSettings
 *.csproj
 *.sln
 *.DotSettings
+*.user
 .idea/
 # some random downloaded assets
 Assets/imported/
diff --git a/Assets/Entities/Mortal.cs b/Assets/Entities/Mortal.cs
index 568787f..3fccdee 100644
--- a/Assets/Entities/Mortal.cs
+++ b/Assets/Entities/Mortal.cs
@@ -27,7 +27,7 @@ namespace FastArena
 
         public void Kill()
         {
-            Destroy(this.gameObject);
+            Destroy(gameObject);
         }
     }
 }
\ No newline at end of file
diff --git a/Assets/Network/Client.cs b/Assets/Network/Client.cs
index 8165b45..c991134 100644
--- a/Assets/Network/Client.cs
+++ b/Assets/Network/Client.cs
@@ -2,37 +2,105 @@
 using System.Collections.Generic;
 using System.Net;
 using System.Net.Sockets;
+using System.Runtime.InteropServices;
+using System.Threading;
+using FastArena.Network.Packets;
 using UnityEngine;
 using Object = UnityEngine.Object;
 
-namespace FastArena
+namespace FastArena.Network
 {
+    public enum ClientStatus
+    {
+        Initialized, Connected, Disconnected
+    }
+
+    public class ServerConnection
+    {
+        public IPAddress Ip;
+        public short PortFirst;
+        public Guid SessionId;
+        public byte[] ServerKey;
+    }
+    
     public static class Client
     {
         private static TcpClient _tcp;
         private static UdpClient _udp;
+        private static byte[] _clientKey;
+        private static ServerConnection _serverConnection;
+        
+        public static ClientStatus Status { get; private set; } = ClientStatus.Initialized;
         
         public static void SendUserAction()
         {
-            throw new System.NotImplementedException();
+            throw new NotImplementedException();
         }
 
         public static void Connect(IPAddress ip, short portFirst)
         {
             _tcp = new TcpClient();
             _udp = new UdpClient();
+            _serverConnection = new ServerConnection()
+            {
+                Ip = ip, PortFirst = portFirst
+            };
+            _udp.Connect(ip, portFirst + 1);
             _tcp.BeginConnect(ip, portFirst, TCPConnectCallback, null);
-            _udp.BeginSend(StructBinaryConverter.GetBytes(new ConnectionRequestUDP()))
         }
 
+        private static void ReadExactly(this TcpClient tcp, byte[] buffer, int offset, int exactSize, int timeoutMs = 5000)
+        {
+            int msPassed = 0;
+            while (tcp.Available < exactSize)
+            {
+                Thread.Sleep(1);
+                msPassed += 1;
+                if (msPassed > timeoutMs)
+                {
+                    throw new TimeoutException(
+                        $"couldn't get {exactSize} bytes from socket, {tcp.Available} avaliable");
+                }
+            }
+
+            int readN = _tcp.GetStream().Read(buffer, offset, exactSize);
+            if (readN != exactSize)
+                throw new Exception($"expected to read {exactSize} bytes, got {readN}");
+        }
+        
         private static void TCPConnectCallback(IAsyncResult ar)
         {
             _tcp.EndConnect(ar);
+            
+            // receive first response from server
+            byte[] buffer = new byte[4096];
+            _tcp.ReadExactly(buffer, 0, Marshal.SizeOf<ConnectionResponseTCP>());
+            //TODO: implement decryption
+            var firstResponse = StructBinaryConverter.ReadStruct<ConnectionResponseTCP>(buffer);
+            firstResponse.ValidateResponseCode();
+            _serverConnection.SessionId = firstResponse.sessionId;
+            _serverConnection.ServerKey = firstResponse.serverKey;
+            
+            // connect udp socket associated with current session
+            byte[] byteMessage = StructBinaryConverter.GetBytes(new ConnectionRequestUDP(_serverConnection.SessionId));
+            //TODO: implement encryption
+            _udp.Send(byteMessage, byteMessage.Length);
+            
+            // receive second response from server
+            IPEndPoint remoteEndpoint = new IPEndPoint(IPAddress.None, 0);
+            byteMessage = _udp.Receive(ref remoteEndpoint);
+            //TODO: implement decryption
+            var secondResponse = StructBinaryConverter.ReadStruct<ConnectionResponseUDP>(byteMessage);
+            secondResponse.ValidateResponseCode();
+            
+            //TODO: start tcp read loop
+            //TODO: start udp read loop
         }
 
-        private static Dictionary<int, SyncTransform> _syncTransforms = new();
+        
+        private static readonly Dictionary<int, SyncTransform> _syncTransforms = new Dictionary<int, SyncTransform>();
 
-        private static void CreateGameObject(int id, ref CreateObjectPacket packet)
+        private static void CreateGameObject(ref CreateObjectPacket packet)
         {
             var prefab = Resources.Load(packet.prefabPath, typeof(GameObject));
             var go = (GameObject)Object.Instantiate(prefab);
@@ -44,9 +112,9 @@ namespace FastArena
             }
         }
         
-        private static void UpdateObjectTransform(int id, ref TransformUpdatePacket packet)
+        private static void UpdateObjectTransform(ref TransformUpdatePacket packet)
         {
-            if(!_syncTransforms.TryGetValue(id, out var component))
+            if(!_syncTransforms.TryGetValue(packet.gameObjectId, out var component))
                 return;
             component.UpdateTransform(ref packet);
         }
diff --git a/Assets/Network/GameObjectId.cs b/Assets/Network/GameObjectId.cs
new file mode 100644
index 0000000..19029ac
--- /dev/null
+++ b/Assets/Network/GameObjectId.cs
@@ -0,0 +1,17 @@
+using System;
+using UnityEngine;
+
+namespace FastArena.Network
+{
+    public class GameObjectId : MonoBehaviour
+    {
+        public int Id { get; private set; } = -1;
+
+        internal void _SetId(int packetGameObjectId)
+        {
+            if (Id != -1)
+                throw new Exception($"GameObjectId is already set to {Id}");
+            Id = packetGameObjectId;
+        }
+    }
+}
\ No newline at end of file
diff --git a/Assets/Network/GameObjectId.cs.meta b/Assets/Network/GameObjectId.cs.meta
new file mode 100644
index 0000000..5e4297c
--- /dev/null
+++ b/Assets/Network/GameObjectId.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: a0274d4d086949a880c5e0b4a9e5cf20
+timeCreated: 1752248822
\ No newline at end of file
diff --git a/Assets/Network/Packets/ConnectionPackets.cs b/Assets/Network/Packets/ConnectionPackets.cs
index 5e83d62..b0d26ec 100644
--- a/Assets/Network/Packets/ConnectionPackets.cs
+++ b/Assets/Network/Packets/ConnectionPackets.cs
@@ -1,21 +1,75 @@
-using System.Runtime.InteropServices;
-using System.Security.Cryptography;
-using UnityEngine;
+using System;
+using System.Runtime.InteropServices;
 
-namespace FastArena
+namespace FastArena.Network.Packets
 {
-    internal struct Hash256
-    
     [StructLayout(LayoutKind.Sequential)]
     internal readonly struct ConnectionRequestTCP
     {
         internal readonly PacketHeader header;
-        private SHA256 _sha256;
+        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 256)]
+        internal readonly byte[] clientKey;
         
-        public ConnectionRequestTCP()
+        public ConnectionRequestTCP(byte[] clientKey)
         {
             header = new PacketHeader(PacketType.ConnectionRequestTCP);
-            
+            this.clientKey = clientKey;
+        }
+    }
+    
+    [StructLayout(LayoutKind.Sequential)]
+    internal readonly struct ConnectionResponseTCP
+    {
+        internal readonly PacketHeader header;
+        internal readonly StatusCode statusCode;
+        internal readonly Guid sessionId;
+        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 256)]
+        internal readonly byte[] serverKey;
+        
+        public ConnectionResponseTCP(StatusCode statusCode, Guid sessionId, byte[] serverKey)
+        {
+            header = new PacketHeader(PacketType.ConnectionResponseTCP);
+            this.statusCode = statusCode;
+            this.sessionId = sessionId;
+            this.serverKey = serverKey;
+        }
+
+        public void ValidateResponseCode()
+        {
+            if (statusCode != StatusCode.OK)
+                throw new StatusCodeException(statusCode);
+        }
+    }
+    
+    [StructLayout(LayoutKind.Sequential)]
+    internal readonly struct ConnectionRequestUDP
+    {
+        internal readonly PacketHeader header;
+        internal readonly Guid sessionId;
+        
+        public ConnectionRequestUDP(Guid sessionId)
+        {
+            header = new PacketHeader(PacketType.ConnectionRequestUDP);
+            this.sessionId = sessionId;
+        }
+    }
+    
+    [StructLayout(LayoutKind.Sequential)]
+    internal readonly struct ConnectionResponseUDP
+    {
+        internal readonly PacketHeader header;
+        internal readonly StatusCode statusCode;
+        
+        public ConnectionResponseUDP(StatusCode statusCode)
+        {
+            header = new PacketHeader(PacketType.ConnectionResponseUDP);
+            this.statusCode = statusCode;
+        }
+        
+        public void ValidateResponseCode()
+        {
+            if (statusCode != StatusCode.OK)
+                throw new StatusCodeException(statusCode);
         }
     }
 }
\ No newline at end of file
diff --git a/Assets/Network/Packets/CreateObjectPacket.cs b/Assets/Network/Packets/CreateObjectPacket.cs
index 8ba7ef4..2d911e6 100644
--- a/Assets/Network/Packets/CreateObjectPacket.cs
+++ b/Assets/Network/Packets/CreateObjectPacket.cs
@@ -1,18 +1,19 @@
 using System.Runtime.InteropServices;
 
-namespace FastArena;
-
-[StructLayout(LayoutKind.Sequential)]
-internal readonly struct CreateObjectPacket
+namespace FastArena.Network.Packets
 {
-    internal readonly PacketHeader header;
-    internal readonly int gameObjectId;
-    internal readonly string prefabPath;
-
-    internal CreateObjectPacket(int _gameObjectId, string _prefabPath)
+    [StructLayout(LayoutKind.Sequential)]
+    internal readonly struct CreateObjectPacket
     {
-        header = new PacketHeader(PacketType.CreateObject);
-        gameObjectId = _gameObjectId;
-        prefabPath = _prefabPath;
+        internal readonly PacketHeader header;
+        internal readonly int gameObjectId;
+        internal readonly string prefabPath;
+
+        internal CreateObjectPacket(int _gameObjectId, string _prefabPath)
+        {
+            header = new PacketHeader(PacketType.CreateObject);
+            gameObjectId = _gameObjectId;
+            prefabPath = _prefabPath;
+        }
     }
 }
\ No newline at end of file
diff --git a/Assets/Network/Packets/PacketHeader.cs b/Assets/Network/Packets/PacketHeader.cs
index 8b52847..7b7b79a 100644
--- a/Assets/Network/Packets/PacketHeader.cs
+++ b/Assets/Network/Packets/PacketHeader.cs
@@ -1,6 +1,6 @@
 using System.Runtime.InteropServices;
 
-namespace FastArena
+namespace FastArena.Network.Packets
 {
     internal enum PacketType : ushort
     {
diff --git a/Assets/Network/Packets/PacketParser.cs b/Assets/Network/Packets/PacketParser.cs
index 11424e1..352874f 100644
--- a/Assets/Network/Packets/PacketParser.cs
+++ b/Assets/Network/Packets/PacketParser.cs
@@ -1,15 +1,16 @@
-namespace FastArena;
-
-internal static class PacketParser
+namespace FastArena.Network.Packets
 {
-    internal static PacketType ReadHeader(byte[] data)
+    internal static class PacketParser
     {
-        var h = StructBinaryConverter.ReadStruct<PacketHeader>(data);
-        return h.magic == PacketHeader.MAGIC_CONST ? h.type : PacketType.Invalid;
-    }
+        internal static PacketType ReadHeader(byte[] data)
+        {
+            var h = StructBinaryConverter.ReadStruct<PacketHeader>(data);
+            return h.magic == PacketHeader.MAGIC_CONST ? h.type : PacketType.Invalid;
+        }
 
-    internal static T ReadPacket<T>(byte[] data) where T : unmanaged
-    {
-        return StructBinaryConverter.ReadStruct<T>(data);
+        internal static T ReadPacket<T>(byte[] data) where T : unmanaged
+        {
+            return StructBinaryConverter.ReadStruct<T>(data);
+        }
     }
 }
\ No newline at end of file
diff --git a/Assets/Network/Packets/StructBinaryConverter.cs b/Assets/Network/Packets/StructBinaryConverter.cs
new file mode 100644
index 0000000..6364c40
--- /dev/null
+++ b/Assets/Network/Packets/StructBinaryConverter.cs
@@ -0,0 +1,46 @@
+using System.Runtime.InteropServices;
+
+namespace FastArena.Network.Packets
+{
+    public static class StructBinaryConverter
+    {
+        public static byte[] GetBytes<T>(T s) where T : struct
+        {
+            return GetBytes(ref s);
+        }
+        
+        public static byte[] GetBytes<T>(ref T s) where T : struct
+        {
+            int size = Marshal.SizeOf<T>();
+            // TODO: implement array pool
+            byte[] buffer = new byte[size];
+            // tel GC to not move the buffer in memory
+            var handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
+            try
+            {
+                Marshal.StructureToPtr(s, handle.AddrOfPinnedObject(), false);
+            }
+            finally
+            {
+                handle.Free();
+            }
+            return buffer;
+        }
+
+        public static T ReadStruct<T>(byte[] buffer) where T : struct
+        {
+            T s;
+            // tel GC to not move the buffer in memory
+            var handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
+            try
+            {
+                s = (T)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(T));
+            }
+            finally
+            {
+                handle.Free();
+            }
+            return s;
+        }
+    }
+}
\ No newline at end of file
diff --git a/Assets/Network/StructBinaryConverter.cs.meta b/Assets/Network/Packets/StructBinaryConverter.cs.meta
similarity index 100%
rename from Assets/Network/StructBinaryConverter.cs.meta
rename to Assets/Network/Packets/StructBinaryConverter.cs.meta
diff --git a/Assets/Network/Packets/TransformUpdatePacket.cs b/Assets/Network/Packets/TransformUpdatePacket.cs
index 8951f4c..031e061 100644
--- a/Assets/Network/Packets/TransformUpdatePacket.cs
+++ b/Assets/Network/Packets/TransformUpdatePacket.cs
@@ -1,21 +1,22 @@
 using System.Runtime.InteropServices;
 using UnityEngine;
 
-namespace FastArena;
-
-[StructLayout(LayoutKind.Sequential)]
-internal readonly struct TransformUpdatePacket
+namespace FastArena.Network.Packets
 {
-    internal readonly PacketHeader header;
-    internal readonly int gameObjectId; 
-    internal readonly Vector3 position;
-    internal readonly Quaternion rotation;
-
-    internal TransformUpdatePacket(int _gameObjectId, Transform transform)
+    [StructLayout(LayoutKind.Sequential)]
+    internal readonly struct TransformUpdatePacket
     {
-        header = new PacketHeader(PacketType.TransformUpdate);
-        gameObjectId = _gameObjectId;
-        position = transform.position;
-        rotation = transform.rotation;
+        internal readonly PacketHeader header;
+        internal readonly int gameObjectId; 
+        internal readonly Vector3 position;
+        internal readonly Quaternion rotation;
+
+        internal TransformUpdatePacket(int _gameObjectId, Transform transform)
+        {
+            header = new PacketHeader(PacketType.TransformUpdate);
+            gameObjectId = _gameObjectId;
+            position = transform.position;
+            rotation = transform.rotation;
+        }
     }
 }
\ No newline at end of file
diff --git a/Assets/Network/Server.cs b/Assets/Network/Server.cs
index ca50c77..c551ee2 100644
--- a/Assets/Network/Server.cs
+++ b/Assets/Network/Server.cs
@@ -2,9 +2,10 @@
 using System.Collections.Generic;
 using System.Net;
 using System.Net.Sockets;
+using FastArena.Network.Packets;
 using UnityEngine;
 
-namespace FastArena
+namespace FastArena.Network
 {
     public class ServerConfig
     {
@@ -33,7 +34,7 @@ namespace FastArena
             }
         }
 
-        public static List<ClientConnection> connections = new List<ClientConnection>();
+        public static readonly List<ClientConnection> Connections = new List<ClientConnection>();
         
         public static void Start(ServerConfig config)
         {
@@ -49,7 +50,7 @@ namespace FastArena
         {
             var tcpClient = _tcp.EndAcceptTcpClient(ar);
             var connection = new ClientConnection(tcpClient);
-            connections.Add(connection);
+            Connections.Add(connection);
         }
         
         private static void UdpReceiveCallback(IAsyncResult ar)
@@ -83,7 +84,7 @@ namespace FastArena
         public static void SendTransformUpdate(int id, Transform transform)
         {
             byte[] data = StructBinaryConverter.GetBytes(new TransformUpdatePacket(id, transform));
-            foreach(var p in connections)
+            foreach(var p in Connections)
             {
                 UdpSendTo(data, p);
             }
diff --git a/Assets/Network/StatusCode.cs b/Assets/Network/StatusCode.cs
new file mode 100644
index 0000000..dbf69f2
--- /dev/null
+++ b/Assets/Network/StatusCode.cs
@@ -0,0 +1,22 @@
+using System;
+
+namespace FastArena.Network
+{
+    public enum StatusCode
+    {
+        OK, 
+        ServerError,
+        AccessNotAllowed
+    }
+
+    public class StatusCodeException : Exception
+    {
+        public StatusCode Code;
+        
+        public StatusCodeException(StatusCode code) : 
+            base($"Status code {(int)code} ({code})")
+        {
+            Code = code;
+        }
+    }
+}
\ No newline at end of file
diff --git a/Assets/Network/StatusCode.cs.meta b/Assets/Network/StatusCode.cs.meta
new file mode 100644
index 0000000..5c3fe62
--- /dev/null
+++ b/Assets/Network/StatusCode.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 6ef3bf843e27438cbaae508f73654ec6
+timeCreated: 1752246290
\ No newline at end of file
diff --git a/Assets/Network/StructBinaryConverter.cs b/Assets/Network/StructBinaryConverter.cs
deleted file mode 100644
index 2ab33a9..0000000
--- a/Assets/Network/StructBinaryConverter.cs
+++ /dev/null
@@ -1,55 +0,0 @@
-using System;
-using System.Runtime.InteropServices;
-
-namespace FastArena
-{
-    public static class StructBinaryConverter
-    {
-        public static byte[] GetBytes<T>(T s) where T : unmanaged
-        {
-            return GetBytes(ref s);
-        }
-        
-        public static byte[] GetBytes<T>(ref T s) where T : unmanaged
-        {
-            int size = Marshal.SizeOf(typeof(T));
-            byte[] buffer = System.Buffers.ArrayPool<byte>.Shared.Rent(Marshal.SizeOf<T>());
-            
-            var handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
-
-            unsafe
-            {
-                fixed (T* s_ptr = &s)
-                {
-                    Marshal.Copy((IntPtr)s_ptr, buffer, 0, size);
-                    Marshal.StructureToPtr();
-                }
-            }
-            try
-            {
-                Marshal.StructureToPtr(msg_struct, handle.AddrOfPinnedObject(), false);
-                return buffer;
-            }
-            finally
-            {
-                handle.Free();
-                ArrayPool<byte>.Shared.Return(buffer);
-            }
-
-        }
-
-        public static T ReadStruct<T>(byte[] buffer) where T : unmanaged
-        {
-            GCHandle handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
-            try
-            {
-                T s = (T)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(T));
-                return s;
-            }
-            finally
-            {
-                handle.Free();
-            }
-        }
-    }
-}
\ No newline at end of file
diff --git a/Assets/Network/SyncTransform.cs b/Assets/Network/SyncTransform.cs
index 0b92f9a..c906a57 100644
--- a/Assets/Network/SyncTransform.cs
+++ b/Assets/Network/SyncTransform.cs
@@ -1,20 +1,8 @@
-using System;
+using FastArena.Network.Packets;
 using UnityEngine;
 
-namespace FastArena
+namespace FastArena.Network
 {
-    public class GameObjectId : MonoBehaviour
-    {
-        public int Id { get; private set; } = -1;
-
-        internal void _SetId(int packetGameObjectId)
-        {
-            if (Id != -1)
-                throw new Exception($"GameObjectId is already set to {Id}");
-            Id = packetGameObjectId;
-        }
-    }
-    
     /// <summary>
     /// Component fetching GameObject's Transform from the server every tick.
     /// </summary>
diff --git a/Packages/manifest.json b/Packages/manifest.json
index 4597d37..d454f1e 100644
--- a/Packages/manifest.json
+++ b/Packages/manifest.json
@@ -1,7 +1,7 @@
 {
   "dependencies": {
-    "com.unity.ide.rider": "3.0.28",
-    "com.unity.ide.visualstudio": "2.0.22",
+    "com.unity.ide.rider": "3.0.36",
+    "com.unity.ide.visualstudio": "2.0.23",
     "com.unity.ide.vscode": "1.2.5",
     "com.unity.textmeshpro": "2.1.6",
     "com.unity.ugui": "1.0.0",
diff --git a/Packages/packages-lock.json b/Packages/packages-lock.json
index f44d5a4..a58cc8c 100644
--- a/Packages/packages-lock.json
+++ b/Packages/packages-lock.json
@@ -8,7 +8,7 @@
       "url": "https://packages.unity.com"
     },
     "com.unity.ide.rider": {
-      "version": "3.0.28",
+      "version": "3.0.36",
       "depth": 0,
       "source": "registry",
       "dependencies": {
@@ -17,7 +17,7 @@
       "url": "https://packages.unity.com"
     },
     "com.unity.ide.visualstudio": {
-      "version": "2.0.22",
+      "version": "2.0.23",
       "depth": 0,
       "source": "registry",
       "dependencies": {