. Lots of questions came in my mind! T1 can carry 24 digitized voice channels or 1.544 Mbps bandwidth, and it is generally thought of as Fibre or even Copper Lines terminating at your end. whats yours? If T1 is for a backbone link, you might have a router, L-3 switch or whatever that intercepts the packets/data/voice. Now, which firewall are you talking about ? Firewall to be put before the packets/data/voice reach your network, or something , which isnt on my head right now ? Some of the firewalls, you might consider are: 1. Sonicwall, Juniper-integrated firewall support, Watchguard, Cisco PIX .. so on 2. If you want a machine to be put, try on iptables, ipf or so... ( there are lots ) If you have to setup a test environment only, go with low commodity hardwares and configure a software firewall from option 2. But obviously, adding firewalls come up as a requirement and people know they have to pay big bucks. See what the bucks and resource requirements are and choose any of the first options . That would be your best bet.