Disabling my Mac's broadcast on Port 5353

[Jake Peters]

We have several Macs running OSX on a LAN, each of which is broadcasting on Port 5353 -- so I've been told by "big brother", who oversees the entire computer firewalled network for my agency (the LAN is connected to a WAN). I've been told to shut it off (port 5353 on each Mac). After reading many notes and posts about iChat, Rendezvous, and iTunes, the main programs that seem to use this port, I still don't know how to shut it off, and what the consequences are if I did.

HELP!!!!

Cheers,
Jake Peters