Depends on what you mean.
If you own a valid license of AE, you can install the render engine on as many machines as you'd like. That means you can have network machines rendering your AE project without actually having AE on the machines - read the help files for more on this - and take note of any issues you may have with 3rd party plug-ins - they'd have to be installed on each of those machines if you are using those effects.
As far as how your network is set up computer to computer or computer to Router to Computer - that's a whole other thing. You do need to have a network set up though, even if it's a network of 2.
Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
Internet Killed the Video Star: A Guide to Creating Video for the Web
