Possibly. In the Netherlands most universities are in such a 'roaming
consortium' to provide guest access to eachothers wireless LANs based on
802.1X+RADIUS. Some universities want to know the real identity of a
user in case of abuse. The alternative is to agree on a logging format
so that abuse can be tracked down by contacting the home organisation of
the user, but this may be difficult (many log entries for
anonymous@university-a.nl) and requires in any case a lot of coordination.
And a bit further along the road, possibly the visited institution wants
to do more advance authorisation based on the identity of the user (did
he complete math101, is he a staff member etc.)
Can this particular scenario be handled by the attributes that exist
(User-Name, Class) or are being discussed (Billable-Identity)?