Need Clarification on Fedearted Portal Network

Hi Experts,

Need clarification on below points for FPN. Even few links or discussion forums regarding the same would be of great help.

1. Should a user be present in producer portal always?
2. When a remote role is assigned to a user in consumer portal, will the same user be created in producer portal too? If user is not created automatically in producer portal, what happens to the assigned remote role in consumer portal, does it fail?
3. Is it mandatory for a user to exist in both consumer and producer portals?
4. If a user is present in both the portals, assigning a remote role in consumer portal will automatically show up in the producer portal role assignments for this user?
5. If user need not exist in producer portal, how is the remote role assignment for a user from consumer portal tracked in producer portal?
6. How can we get the group and role associations either from consumer or producer portals?

Awaiting quick response!!

Thanks

Sriram