Federated Security Applications and Implications.

["Shaji Sethu" <ssethu () micros com>]

All,
Recently I have been investigating requirements to build a pseudo P2P (uses
a combination of P2P and Client Server) distributed application based on XML
web services. The main requirement for the application has to be such that
secure domains can join or leave the application network without much
effort. The platform has not been finalised yet but my preference is .NET.
Considering the requirements a Federated Architecture for security comes to
mind, the only application that comes close to it is the Liberty One from
Sun. I had talked to the local Microsoft guys in Australia and they
suggested Trust Bridge which was due for shipment with Windows 2003 and
their specifications were a bit vague and pointed me to a msdn web site with
5 lines explaining it.

The question is: 
1. Is there any solution out there which implements federated security model
where security domains can easily join and leave without complex system
administration. 
2. Are there any white papers or research papers published on this (BTW I
have gone through the ACM archives without much luck)?
3. Has anyone looked at the security implications of this and WS-Security?
4. Is this viable or does this technology has the pie in the sky status?

Thanks for any help on this.

Best Regards.

Shaji Sethu
System Developer
myFidelio.net
Web:    www.micros.com