comp.dcom.lans.ethernet - join
Discussions of the Ethernet/IEEE 802.3 protocols.
Low activity, 511 subscribers, Usenet

comp.protocols.tcp-ip - join
TCP and IP network protocols.
Low activity, 1776 subscribers, Usenet

comp.dcom.sys.cisco - join
Info on Cisco routers and bridges.
Low activity, 5454 subscribers, Usenet