I have an interesting problem while trying to access a Windows 2008 Server from wireless clients. While maintaing a constant ping to ANY windows 2008 Server Standard machine, the client will roam to another access point. When this happens the ping will time out for between 5 - 10 seconds and the resume. This happens from both wireless laptops, and hand held computers. Pinging other devices such as the default gateway, machines running Windows XP, or Windows Vista do not have this problem. Also, it would appear to not so much being a problem with roaming, but actually switching ports on the network switch. This same problem happens as clients switch from wired to wireless. As soon as the traffic starts through a different port on the network switch, a delay in connectivity for about 5 to 10 seconds is experienced on only Windows 2008 Server.

It turns out to be a problem not with Windows, but with the router. The router was using ARP proxy. Whenver a device roamed to another access point the device would send out an ARP request. A response was being sent from the router in an attempt to proxy the traffic. Once the ARP proxy was disabled, the problem was solved.