Good points, but it makes me comment that it would be nice to somehow
have a server process or computer be able to operate in multiple
realms.

realm foo.com   with servers at a.foo.com, b.foo.com, a.bar.com
realm bar.com with servers at a.bar.com, b.bar.com, a.foo.com

sort of like backup dns arrangements.

In this case the a.foo.com server functions for foo and bar, but those
uses are logically independent, different authentication, etc.
I just wanted to throw out this concept as we slowly moved towards a
useful realization of the security/authentication/encryption model.

-- 
        Greg Troxel <gdt_at_ir.bbn.com>