diff --git a/src/main/java/mc/protocol/ProtocolConstant.java b/src/main/java/mc/protocol/ProtocolConstant.java
new file mode 100644
index 0000000..bbf9292
--- /dev/null
+++ b/src/main/java/mc/protocol/ProtocolConstant.java
@@ -0,0 +1,10 @@
+package mc.protocol;
+
+import lombok.experimental.UtilityClass;
+
+@UtilityClass
+public class ProtocolConstant {
+
+    public final int PROTOCOL_VERSION = 47;
+    public final String PROTOCOL_VERSION_VALUE = "1.8.8";
+}
diff --git a/src/main/java/mc/protocol/UnknownPacket.java b/src/main/java/mc/protocol/UnknownPacket.java
new file mode 100644
index 0000000..d953e8d
--- /dev/null
+++ b/src/main/java/mc/protocol/UnknownPacket.java
@@ -0,0 +1,27 @@
+package mc.protocol;
+
+import lombok.Data;
+import lombok.ToString;
+import mc.protocol.io.NetInputStream;
+import mc.protocol.io.NetOutputStream;
+
+@Data
+@ToString(exclude = "rawData")
+public class UnknownPacket implements Packet {
+
+    private final State state;
+    private final int id;
+    private final int dataSize;
+    private byte[] rawData;
+
+    @Override
+    public void readSelf(NetInputStream netInputStream) {
+        rawData = new byte[dataSize];
+        netInputStream.readBytes(rawData);
+    }
+
+    @Override
+    public void writeSelf(NetOutputStream netOutputStream) {
+        netOutputStream.writeBytes(rawData);
+    }
+}
diff --git a/src/main/java/mc/protocol/Utils.java b/src/main/java/mc/protocol/Utils.java
new file mode 100644
index 0000000..d5fbe79
--- /dev/null
+++ b/src/main/java/mc/protocol/Utils.java
@@ -0,0 +1,17 @@
+package mc.protocol;
+
+import lombok.experimental.UtilityClass;
+
+@UtilityClass
+public class Utils {
+
+    public int sizeOfVarInt(int value) {
+        for (int i = 1; i < 5; ++i) {
+            if ((value & -1 << i * 7) == 0) {
+                return i;
+            }
+        }
+
+        return 5;
+    }
+}
diff --git a/src/main/java/mc/protocol/handshake/client/HandshakePacket.java b/src/main/java/mc/protocol/handshake/client/HandshakePacket.java
index 6f72ed9..7a70ba2 100644
--- a/src/main/java/mc/protocol/handshake/client/HandshakePacket.java
+++ b/src/main/java/mc/protocol/handshake/client/HandshakePacket.java
@@ -30,14 +30,14 @@ import mc.protocol.io.NetOutputStream;
 public class HandshakePacket implements Packet {
 
     private int protocolVersion;
-    private String ip;
+    private String host;
     private int port;
     private State nextState;
 
     @Override
     public void readSelf(NetInputStream netInputStream) {
         protocolVersion = netInputStream.readVarInt();
-        ip = netInputStream.readString(255);
+        host = netInputStream.readString(255);
         port = netInputStream.readUnsignedShort();
         nextState = State.getById(netInputStream.readVarInt());
     }
@@ -45,7 +45,7 @@ public class HandshakePacket implements Packet {
     @Override
     public void writeSelf(NetOutputStream netOutputStream) {
         netOutputStream.writeVarInt(protocolVersion);
-        netOutputStream.writeString(ip);
+        netOutputStream.writeString(host);
         netOutputStream.writeShort(port);
         netOutputStream.writeVarInt(nextState.getId());
     }
diff --git a/src/main/java/mc/protocol/io/coder/ProtocolDecoder.java b/src/main/java/mc/protocol/io/coder/ProtocolDecoder.java
index 4acad4c..b6fd920 100644
--- a/src/main/java/mc/protocol/io/coder/ProtocolDecoder.java
+++ b/src/main/java/mc/protocol/io/coder/ProtocolDecoder.java
@@ -1,13 +1,9 @@
 package mc.protocol.io.coder;
 
 import lombok.RequiredArgsConstructor;
-import mc.protocol.Packet;
-import mc.protocol.PacketDirection;
-import mc.protocol.State;
+import mc.protocol.*;
 import mc.protocol.io.NetInputStream;
 
-import java.util.Objects;
-
 @RequiredArgsConstructor
 public class ProtocolDecoder {
 
@@ -19,15 +15,24 @@ public class ProtocolDecoder {
 
         int packetId = netInputStream.readVarInt();
         Class<? extends Packet> packetClass = state.getPacketById(direction, packetId);
-        Objects.requireNonNull(packetClass);
-
-        try {
-            Packet packet = packetClass.newInstance();
+        if (packetClass == null) {
+            //FIXME необходимо в лог пивать предупреждение
+            UnknownPacket packet = new UnknownPacket(
+                    state,
+                    packetId,
+                    sizePacket - Utils.sizeOfVarInt(packetId)
+            );
             packet.readSelf(netInputStream);
             return packet;
-        } catch (InstantiationException | IllegalAccessException e) {
-            e.printStackTrace(); //FIXME нужно писать в лог
-            return null;
+        } else {
+            try {
+                Packet packet = packetClass.newInstance();
+                packet.readSelf(netInputStream);
+                return packet;
+            } catch (InstantiationException | IllegalAccessException e) {
+                e.printStackTrace(); //FIXME нужно писать в лог
+                return null;
+            }
         }
     }
 }