1. SIP-T Status Update Jon Peterson Level(3) Communications 49 th IETF

2. What is SIP-T? SIP for Telephones Not an extension to SIP – a set of practices for interfacing SIP to the PSTN –Encapsulation of ISUP in SIP –Translation of ISUP parameters to SIP headers Implemented at PSTN gateways, and carried end- to-end Makes as few assumptions as possible about the SIP networks it traverses

3. PSTN GW Proxy Server Proxy Server IAM INVITE (IAM) SIP-T in a Network (1)

4. PSTN GW Proxy Server Proxy Server IAM INVITE (IAM) SIP-T in a Network (2) INVITE (IAM) INVITE (IAM) IAM Reuse of ISUP at terminating gateway

5. PSTN GW Proxy Server Proxy Server IAM INVITE (IAM) SIP-T in a Network (3) INVITE (IAM) INVITE (IAM) Non-gateway ignores ISUP

6. SIP-T Context and Architectures Describes a context for the use of SIP-T –As seen in the preceding slides –Defines the problem space of SIP-T Addition of SIP content negotiation Encryption or omission of ISUP when the signaling passes to an untrusted source To become the new umbrella doc?

7. ISUP MIME draft Defines a MIME type so ISUP can be carried in SIP WG Last Call has passed Several amendations since last IETF –IANA language for variants Registered strings vs. X- strings –Content-Disposition header signal v. session

8. Work related to SIP-T LNP and Freephone indicators in tel URL –draft-yu-tel-url-01 SIP-ISUP Mapping draft –draft-camarillo-sip-isup-00