1. App Interaction Jonathan Rosenberg dynamicsoft

2. Context Param INVITE Call-ID:A From:caller;tag=B To:callee;tag=C Supported: context INVITE/200 REFER sip:gruu Refer-To: http://foo.com;http://foo.com context=“B,C,A” Require: context GET http://foo.com 1 2 3 4

3. Other Changes Added motivation text from KPML SIP Identity Informative Reference Usage of Reg Event to learn capabilities of device Authorizing REFER/SUB – cannot be automatic w/o sips Softened wording about app in dialog path Updated examples to use TLS, crypto- random identifiers IANA registries for context parameters

4. Next Steps No open issues Ready for WGLC

5. NAT Scenarios Jonathan Rosenberg dynamicsoft

6. History Individual draft, July 2001 –Team effort between myself, Rohan Mahy, Sanjoy Sen of Nortel –Contains lots of flows, lots of different solutions, no recommendations Made working item, June 2002 Abandoned October 2003 –Gave the message that we didn’t have a solution that coherently works ICE Scenarios October 2003 –Reverted to individual draft with ICE example flows –Told the community that this is how to make it work Concerns from the community about scope Kept on life support with two revisions since then –Minor additions, such as v4 to v6 transition scenarios

7. Proposed Goals Make it clear to the community that we have a solution for the problem that works consistently across deployment scenarios Make use of approved and standards tracked IETF specifications Scope is SIP and offer/answer –RFC 3581 (rport), connect-reuse, STUN, TURN, ICE, GRUU

8. High Level Outline Problem Statement and Motivation Overview of IETF Solution –References to specifications –Unstated wisdom Call flows with different types of NAT Call flows with different topologies Third Party Call Control V6/V4 Cases

9. Path Forward Chris Boulton recruited to take over primary editorship as part of mentor program Will work out outline and distribute on list Resubmit existing document as draft-ietf Submit revised document based on outline Submit document after all input specs are done