Speaker：Wenping Zhang Date：2008/01/23 Message Session Relay Protocol Adaptation for Interactive Connectivity Establishment (ICE) draft-niemi-simple-msrp-ice-00 Speaker：Wenping Zhang Date：2008/01/23

Outline Introduction Overview of Operation Generating SDP offer Generation SDP Answer Reference

Introduction The Message Session Relay Protocol (MSRP) defines a mechanism for transmitting a series of related instant messages in the context of a session. This session is established using a separate session negotiation protocol, such as the Session Initiation Protocol (SIP) , and the Offer/Answer Model with the Session Description Protocol (SDP) .

Overview of Operation To initiate an MSRP session, the initiator collects ICE candidates, each of which are one of three types: An active candidate for which the agent will attempt to open a TCP connection A passive candidate for which the agent will be in passive mode and only listen for incoming connections Simultaneous open candidate, for which the agents will attempt a TCP simultaneous open

Generating SDP Offer v=0 o=jdoe 2890844526 2890842807 IN IP4 s= c=IN IP4 192.0.2.3 t=0 0 a=ice-pwd:asd88fgpdd777uzjYhagZg a=ice-ufrag:8hhY m=message 7746 TCP/MSRP * a=accept-types:text/plain a=path:msrp://192.0.2.3:7746/asd88fgpdd777uzjYhagZg;tcp a=candidate:1 1 tcp-so 2130706178 10.0.0.5 12534 typ local a=candidate:2 1 tcp-pass 2130706178 10.0.0.5 12534 typ local a=candidate:3 1 tcp-so 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534 a=candidate:4 1 tcp-act 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534 a=candidate:5 1 tcp-pass 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534 a=candidate:6 1 tcp-pass 1694498562 192.0.2.3 7746 typ relay raddr 10.0.0.5 rport 12534

Generating SDP Answer v=0 o=jdoe 2890844526 2890842807 IN IP4 s= c=IN IP4 192.0.2.3 t=0 0 a=ice-pwd:asd88fgpdd777uzjYhagZg a=ice-ufrag:8hhY m=message 7746 TLS/MSRP a=setup:holdconn # Also useless... a=connection:existing a=fingerprint:SHA-1 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:5D:49:6B:19:E5:7C:AB a=accept-types:text/plain a=path:msrp://192.0.2.3:7746/asd88fgpdd777uzjYhagZg a=candidate:1 1 tls-so 2130706178 10.0.0.5 12534 typ local a=candidate:2 1 tls-act 2130706178 10.0.0.5 12534typ local a=candidate:3 1 tls-pass 2130706178 10.0.0.5 12534 typ local a=candidate:4 1 tls-so 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534 a=candidate:5 1 tls-act 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534 a=candidate:6 1 tls-pass 1694498562 192.0.2.3 7746 typ srflx raddr 10.0.0.5 rport 12534

Reference Message Session Relay Protocol Adaptation for Interactive Connectivity Establishment (ICE) RFC4975 The Message Session Relay Protocol