NAC devices - opinions sought

[David Boyer <David () BVU EDU>]

Anyone familiar with Ciscos Network Admission Control (formerly Cisco Clean Access, formerly Perfigo), Juniper 
Infranet, Symantec Network Access Control or similar software/appliances?
 
Like many schools, we have a 1:1 ration of computers to students. We'd like to avoid letting vulnerable or 
malware-infected systems onto our network while simultaneously addressing the infection or vulnerability. Almost all of 
our systems are running Windows XP or Windows 2000.
 
I'd be interested in hearing about your experiences with these or similar solutions. Any open-source solutions that you 
know of?
 
Thanks in advance,
 
David Boyer
Buena Vista University