1. What is the "right" definition of reliable multicast?

• Is there a baseline(e.g., reliable delivery of all data)?
• should ordering/causality be part of the networking semantics of reliable multicast?
• where to draw the line between network- and application-level functionality?

2. Design Approaches

• How important is scalability (large number of participants)?
• Are there fundamental differences from one setting to another (1-many versus many-many) that require different approaches?
• are separate designs, each optimized for a different scenario, the way to go?
• can one protocol (or protocol framework) fit all requirements? Will n protocols (or framworks) fit k (n<k) scenarios?

3. Framework.

• Is there a value (and if so, what is it) of developing a common framework (a la RTP) in which various reliable multicast protocols can be built
• what should that framework look like?
• in terms of IETF, is there any part (which one) that should be standardized?