1. GRUU Jonathan Rosenberg Cisco Systems

2. sip and sips General problem –What should gruu say about relationship of sips to gruu? Specific questions –If the contact URI is sip, can the gruu be sips? –If the contact URI is sips, should the gruu be sips? –What if To/From are a mix of sip/sips? –Do we require one vs. two registrations? Meta-question –Are a sip and sips URI for a resource the same resource? [Adam reports yes] –Can a URI be downgraded?

3. Proposal If a sip and sips URI exist, they should point to the same resource Existence of sip doesn’t imply sips and vice a versa If contact is sip, gruu is a sip URI, but the server creates the sips resource (i.e., it will accept and handle sips if it can do a secure connection) If the contact is sips, the gruu is sips, but the server does not create the sip resource –Allows for sips only resources

4. Connection Reuse/GRUU relationship draft-jennings-sipping-outbound represents the client to server aspect of connection reuse –Allows multiple connections from a client –Each is to the same instance –Differentiated with connection ID parameter Those connections represent different contacts to the same instance No normative reference needed

5. Multiple contacts allowed? Currently, can only have one contact per instance But an instance can be reachable in many ways for redundancy Propose: allow multiple contacts per GRUU, all to same instance

6. Conflict Resolution Current spec allows a single contact per instance –On failure and reboot, need multiple transactions to remove old registered contact –Impacts avalanche restart problem Options –New contact overwrites previous one (had previously rejected this approach) –New contact gets registered too (only to same instance!) Replacement does occur if you are using the connection reuse

7. Does GRUU map to AOR Right now, AOR maps to a contact –How are redirects handled? Do you redirect to GRUU or contact? If you have multiple contacts, you would have different proxy behaviors for AOR->GRUU and GRUU->contacts Proposal –AOR translates to GRUU, translates to Contacts –Registering and refreshing contact registers and refreshes AOR->GRUU mapping and GRUU->contact mapping –AOR->GRUU mapping disappears when no contacts mapped to GRUU

8. Record-Route Interactions Proxy/RegEPClient 12 3 45 EP record routes initial INVITE Client puts GRUU in Contact Causes spiral – ideally EP should not record route if client uses GRUU

9. Solutions If 200 OK contains Supported: GRUU EP can remove RR in response Grin and bear it Others?