I suspect the answer to the question is simply ?No? but you guys may know better
The scenario is as follows:
A wireless infrastructure with Cisco Aironet 1200 access points in over 50 different locations. Each location has a connection back to one central site. There is no wireless coverage between locations, so it's a kind of a hub and spoke topology. The connections back to the central site are Internet based VPN tunnels which are not entirely reliable and may have some latency issues.
The Wireless clients will be installed on Buses. These buses will be moving from location to location. Each time they come within range of an AP they should be automatically authenticated with no manual intervention ? this part is pretty straightforward (I think)
The client devices on the Buses must use PEAP authentication they authenticate to a Windows 2003 server with IAS (Radius) and CA services running at the central site
If the Link to the central site goes down and the IAS server is unavailable, is there any way the clients can authenticate and be given access to the Wireless network?