public byte[] CreateReplyPacket(byte[] data) {

        List<byte> dataStream = new List<byte>();
        userCommand = (Globals.Command)BitConverter.ToInt32(data, 0);

        switch (userCommand) {

            case Globals.Command.Connect:

                dataStream.Clear();
                dataStream.AddRange(BitConverter.GetBytes((int)userCommand));
                Console.WriteLine("Incoming Connection ...");

                break;

            case Globals.Command.Login:

                int usernameLength = BitConverter.ToInt32(data, 4);
                int passwordLength = BitConverter.ToInt32(data, 8);

                if (usernameLength > 0)
                    username = Encoding.UTF8.GetString(data, 12, usernameLength);

                if (passwordLength > 0)
                    password = Encoding.UTF8.GetString(data, 12 + usernameLength, passwordLength);

                bool loginAttempt = Database.LoginAttempt(username, password);

                dataStream.Clear();
                dataStream.AddRange(BitConverter.GetBytes((int)Globals.Command.Login));
                dataStream.AddRange(BitConverter.GetBytes(loginAttempt));

                break;
        }

        return dataStream.ToArray();
    }

private void OnReceive(IAsyncResult AR) {

    IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
    EndPoint epSender = ipeSender;

    int rec = clientSocket.EndReceiveFrom(AR, ref epSender);

    byte[] tmpData = new byte[rec];
    Buffer.BlockCopy(byteData, 0, tmpData, 0, rec);

    Globals.Command cmdReceived = (Globals.Command)BitConverter.ToInt32(tmpData, 0);

    if (cmdReceived == Globals.Command.Connect) {

        messageToDisplay = "Connected to the Server";
        Array.Clear(byteData, 0, tmpData.Length);
        StartListening();

    } else if (cmdReceived == Globals.Command.Login) {

        if (BitConverter.ToBoolean(tmpData, 4)) {

            messageToDisplay = "Succesfully Logged in";
            isAuthenticated = true;
        } else {
            messageToDisplay = "Wrong Username or Password";
        }
    }

}