Cisco vpn on a mac

Having troube the Cisco AnyConnect running on Mac. My wife is uses it to access her works' PC, she on an Macbook Pro 2008ish. It seems like it freezing up our base station extreme. Periodically, the internet goes out and the stuff she's accessing on the vpn freezes. This happens about every 10 minutes of use. The base station is old one of the first ones released. Any thoughts. I wonder if the base station is so old it can't handle the load or the NAT porting? Behind the base station is a comcast cable internet router. She's using wireless to connect.