MEDIUM:
 - replace alarm() with setitimer()
 - TCP support
 
LOW:
 - more comments
 - some more tests on multi-packet support
 - AUTOCONFIG!!
 - use CONTROL BYTE for something useful
     e.g.:
     - better compression negotiation (negotiate compression method too)
     - pinging (to check if remote side is up)
     - identification, authentication
     - encryption
     - Point-to-Multipoint communication
       (maybe with MAC list XChange - like RIP)
 