diff --git a/core/gen/com/riiablo/net/packet/netty/Header.java b/core/gen/com/riiablo/net/packet/netty/Header.java
new file mode 100644
index 00000000..1109b6aa
--- /dev/null
+++ b/core/gen/com/riiablo/net/packet/netty/Header.java
@@ -0,0 +1,41 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+package com.riiablo.net.packet.netty;
+
+import java.nio.*;
+import java.lang.*;
+import java.util.*;
+import com.google.flatbuffers.*;
+
+@SuppressWarnings("unused")
+public final class Header extends Table {
+  public static Header getRootAsHeader(ByteBuffer _bb) { return getRootAsHeader(_bb, new Header()); }
+  public static Header getRootAsHeader(ByteBuffer _bb, Header obj) { _bb.order(ByteOrder.LITTLE_ENDIAN); return (obj.__assign(_bb.getInt(_bb.position()) + _bb.position(), _bb)); }
+  public void __init(int _i, ByteBuffer _bb) { bb_pos = _i; bb = _bb; vtable_start = bb_pos - bb.getInt(bb_pos); vtable_size = bb.getShort(vtable_start); }
+  public Header __assign(int _i, ByteBuffer _bb) { __init(_i, _bb); return this; }
+
+  public int sequence() { int o = __offset(4); return o != 0 ? bb.getShort(o + bb_pos) & 0xFFFF : 0; }
+  public int ack() { int o = __offset(6); return o != 0 ? bb.getShort(o + bb_pos) & 0xFFFF : 0; }
+  public int ackBits() { int o = __offset(8); return o != 0 ? bb.getInt(o + bb_pos) : 0; }
+
+  public static int createHeader(FlatBufferBuilder builder,
+      int sequence,
+      int ack,
+      int ack_bits) {
+    builder.startObject(3);
+    Header.addAckBits(builder, ack_bits);
+    Header.addAck(builder, ack);
+    Header.addSequence(builder, sequence);
+    return Header.endHeader(builder);
+  }
+
+  public static void startHeader(FlatBufferBuilder builder) { builder.startObject(3); }
+  public static void addSequence(FlatBufferBuilder builder, int sequence) { builder.addShort(0, (short)sequence, (short)0); }
+  public static void addAck(FlatBufferBuilder builder, int ack) { builder.addShort(1, (short)ack, (short)0); }
+  public static void addAckBits(FlatBufferBuilder builder, int ackBits) { builder.addInt(2, ackBits, 0); }
+  public static int endHeader(FlatBufferBuilder builder) {
+    int o = builder.endObject();
+    return o;
+  }
+}
+
diff --git a/core/gen/com/riiablo/net/packet/netty/Netty.java b/core/gen/com/riiablo/net/packet/netty/Netty.java
index 4d67307f..00e2129a 100644
--- a/core/gen/com/riiablo/net/packet/netty/Netty.java
+++ b/core/gen/com/riiablo/net/packet/netty/Netty.java
@@ -14,21 +14,26 @@ public final class Netty extends Table {
   public void __init(int _i, ByteBuffer _bb) { bb_pos = _i; bb = _bb; vtable_start = bb_pos - bb.getInt(bb_pos); vtable_size = bb.getShort(vtable_start); }
   public Netty __assign(int _i, ByteBuffer _bb) { __init(_i, _bb); return this; }
 
-  public byte dataType() { int o = __offset(4); return o != 0 ? bb.get(o + bb_pos) : 0; }
-  public Table data(Table obj) { int o = __offset(6); return o != 0 ? __union(obj, o) : null; }
+  public Header header() { return header(new Header()); }
+  public Header header(Header obj) { int o = __offset(4); return o != 0 ? obj.__assign(__indirect(o + bb_pos), bb) : null; }
+  public byte dataType() { int o = __offset(6); return o != 0 ? bb.get(o + bb_pos) : 0; }
+  public Table data(Table obj) { int o = __offset(8); return o != 0 ? __union(obj, o) : null; }
 
   public static int createNetty(FlatBufferBuilder builder,
+      int headerOffset,
       byte data_type,
       int dataOffset) {
-    builder.startObject(2);
+    builder.startObject(3);
     Netty.addData(builder, dataOffset);
+    Netty.addHeader(builder, headerOffset);
     Netty.addDataType(builder, data_type);
     return Netty.endNetty(builder);
   }
 
-  public static void startNetty(FlatBufferBuilder builder) { builder.startObject(2); }
-  public static void addDataType(FlatBufferBuilder builder, byte dataType) { builder.addByte(0, dataType, 0); }
-  public static void addData(FlatBufferBuilder builder, int dataOffset) { builder.addOffset(1, dataOffset, 0); }
+  public static void startNetty(FlatBufferBuilder builder) { builder.startObject(3); }
+  public static void addHeader(FlatBufferBuilder builder, int headerOffset) { builder.addOffset(0, headerOffset, 0); }
+  public static void addDataType(FlatBufferBuilder builder, byte dataType) { builder.addByte(1, dataType, 0); }
+  public static void addData(FlatBufferBuilder builder, int dataOffset) { builder.addOffset(2, dataOffset, 0); }
   public static int endNetty(FlatBufferBuilder builder) {
     int o = builder.endObject();
     return o;
diff --git a/core/src/com/riiablo/net/netty/Netty.fbs b/core/src/com/riiablo/net/netty/Netty.fbs
index b2793465..c4392648 100644
--- a/core/src/com/riiablo/net/netty/Netty.fbs
+++ b/core/src/com/riiablo/net/netty/Netty.fbs
@@ -2,6 +2,12 @@ include "Packets.fbs";
 
 namespace com.riiablo.net.packet.netty;
 
+table Header {
+  sequence:uint16;
+  ack:uint16;
+  ack_bits:int32;
+}
+
 union NettyData {
   Connection,
   Disconnect,
@@ -9,6 +15,7 @@ union NettyData {
 }
 
 table Netty {
+  header:Header;
   data:NettyData;
 }
 
diff --git a/server/netty/src/com/riiablo/server/netty/Client.java b/server/netty/src/com/riiablo/server/netty/Client.java
index 7977e7f7..a177d13b 100644
--- a/server/netty/src/com/riiablo/server/netty/Client.java
+++ b/server/netty/src/com/riiablo/server/netty/Client.java
@@ -1,5 +1,6 @@
 package com.riiablo.server.netty;
 
+import com.google.flatbuffers.ByteBufferUtil;
 import com.google.flatbuffers.FlatBufferBuilder;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.buffer.ByteBuf;
@@ -14,6 +15,7 @@ import io.netty.channel.socket.DatagramChannel;
 import io.netty.channel.socket.DatagramPacket;
 import io.netty.channel.socket.nio.NioDatagramChannel;
 import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
 
 import com.badlogic.gdx.Application;
 import com.badlogic.gdx.ApplicationAdapter;
@@ -23,6 +25,7 @@ import com.badlogic.gdx.backends.headless.HeadlessApplicationConfiguration;
 
 import com.riiablo.codec.Animation;
 import com.riiablo.net.packet.netty.Connection;
+import com.riiablo.net.packet.netty.Header;
 import com.riiablo.net.packet.netty.Netty;
 import com.riiablo.net.packet.netty.NettyData;
 
@@ -71,16 +74,27 @@ public class Client extends ApplicationAdapter {
       InetSocketAddress remoteAddress = (InetSocketAddress) ctx.channel().remoteAddress();
       Gdx.app.log(TAG, "Connecting to " + remoteAddress.getHostString() + ":" + remoteAddress.getPort());
 
-      FlatBufferBuilder builder = new FlatBufferBuilder(0);
+      FlatBufferBuilder builder = new FlatBufferBuilder();
+      int headerOffset = Header.createHeader(builder, 0, 0, 0);
       Connection.startConnection(builder);
       int dataOffset = Connection.endConnection(builder);
-      int offset = Netty.createNetty(builder, NettyData.Connection, dataOffset);
+      int offset = Netty.createNetty(builder, headerOffset, NettyData.Connection, dataOffset);
       Netty.finishSizePrefixedNettyBuffer(builder, offset);
 
+//      sanity(builder.dataBuffer());
+
       ByteBuf byteBuf = Unpooled.wrappedBuffer(builder.dataBuffer());
       ctx.writeAndFlush(byteBuf);
     }
 
+    private void sanity(ByteBuffer buffer) {
+      ByteBuffer tmp = ByteBufferUtil.removeSizePrefix(buffer);
+      Netty netty = Netty.getRootAsNetty(tmp);
+      Gdx.app.log(TAG, "  " + NettyData.name(netty.dataType()));
+      Header header = netty.header(new Header());
+      Gdx.app.log(TAG, "  " + String.format("SEQ:%d ACK:%d ACK_BITS:%08x", header.sequence(), header.ack(), header.ackBits()));
+    }
+
     @Override
     protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket msg) {
 //      ctx.writeAndFlush(msg);
diff --git a/server/netty/src/com/riiablo/server/netty/Main.java b/server/netty/src/com/riiablo/server/netty/Main.java
index 0cfea3b3..44e351a8 100644
--- a/server/netty/src/com/riiablo/server/netty/Main.java
+++ b/server/netty/src/com/riiablo/server/netty/Main.java
@@ -12,6 +12,7 @@ import io.netty.channel.nio.NioEventLoopGroup;
 import io.netty.channel.socket.DatagramChannel;
 import io.netty.channel.socket.DatagramPacket;
 import io.netty.channel.socket.nio.NioDatagramChannel;
+import java.nio.ByteBuffer;
 import org.apache.commons.cli.CommandLine;
 import org.apache.commons.cli.CommandLineParser;
 import org.apache.commons.cli.DefaultParser;
@@ -25,6 +26,7 @@ import com.badlogic.gdx.backends.headless.HeadlessApplicationConfiguration;
 
 import com.riiablo.Riiablo;
 import com.riiablo.codec.Animation;
+import com.riiablo.net.packet.netty.Header;
 import com.riiablo.net.packet.netty.NettyData;
 
 public class Main extends ApplicationAdapter {
@@ -100,8 +102,11 @@ public class Main extends ApplicationAdapter {
       Gdx.app.log(TAG, "Packet from " + msg.sender().getHostName() + ":" + msg.sender().getPort());
       ByteBuf in = msg.content();
       try {
-        Packet packet = Packet.obtain(0, in.nioBuffer());
+        ByteBuffer buffer = in.nioBuffer();
+        Packet packet = Packet.obtain(0, buffer);
         Gdx.app.log(TAG, "  " + NettyData.name(packet.data.dataType()));
+        Header header = packet.data.header(new Header());
+        Gdx.app.log(TAG, "  " + String.format("SEQ:%d ACK:%d ACK_BITS:%08x", header.sequence(), header.ack(), header.ackBits()));
       } finally {
         in.release(); // TODO: release after packet is processed by server
       }