On Thu, 10 Mar 2005 19:56:28 -0000, Peter Crowther <Peter at ozzard.org>  
wrote:

> 1c. The protocol used between client and server, and whether any
> communication is provided between client and client.  This has other
> important consequences, especially if it needs mods to firewalls,
> secondary ports opening, standard client ports, incoming connections, or
> other nasties.
>
<plug> My package 'Tric-Datagram Toolkit' can help there. It does reliable  
UDP and multiplexes over a single socket; this means for Joe Average's NAT  
router that if a single machine on the public internet has received a  
packet from a NAT'ed machine, all other machines may use the NAT info thus  
learned to send packets to the machine. Because of the multiplexing it is  
thus possible to run 'servers' on NATed machines. </plug>