DXX-Rebirth Tracker Protocol:

    Purpose:            Establish dialogue without advertising vernacular in use
                        via port scanner.
    Server State:       Awaiting_Greeting
    Client:             MATERIAL <protocol version >= 1>
    Server:             DEFENDER | (disconnect)
    Server Next State:  Awaiting_User_Agent

    Purpose:            Find out what they are connecting with and determine
                        whether it is permitted or not.
    Server State:       Awaiting_User_Agent
    Client:             USERAGENT <d1x-rebirth|d2x-rebirth> <major> <minor>
    Server:             OK | FAIL [reason] (disconnect)
    Server Next State:  Refreshing | (n/a)

    Purpose:            Send client latest game data.
    Server State:       Refreshing
    Client:             (null)
    Server:             GAME_ADD <address> <port> "<description>"
                        GAME_ADD <address> <port> "<description>"
                        GAME_REM "<description>"
                        GAME_ADD <address> <port> "<description>"
                        ALERT anything here can be displayed as a popup box
    Notes:              The preceding server lines may arrive in any order.