In the simple UC framework paper, there is a brief discussion on session identifiers (sids) on page 13. It states
The main protocol is given a session identifier sid
but it is not entirely clear to me how this happens. I understand that the (S)UC framework requires the sid to be unique and known to all parties.
- Can I just assume that the sid is written to the code tapes of all machines (including the router, adversary and environment) before execution starts (similar to how all security tapes are initialized)? Or is something more subtle going on?
- Does the "main ideal functionality" (page 8: the functionality that creates local copies of the actual functionality) get initialized with the sid?