There are many potential topics spanning the very basic (often spanning both non-federated and federated scenarios) to the very in-depth. The initial WG activity needs to be the pruning/scoping of the effort to identify the critical topics and begin to discuss how to tackle them.
- Authentication
- IdP Discovery
- Logout
- User Identification
- Sessions
- Identity Assurance
- Attributes
- Boarding Process
- Provisioning (incl. Account Activation / Linking)
- Groups
- Authorization / Access Control
- Error Handling
- Federation Trust Management
One of the challenges will be to identify areas where best practice can be agreed on (relatively) non-controversially vs. areas of open debate and disagreement where discussion of alternatives will be more appropriate.
Another scoping point: we (presumably?) don't want to write a guide on how to implement federation. The focus should be on application integration with the concepts we talk about, not the concepts themselves. Background should be sufficient to motivate the developer's work, but no more.