draftminieromediactrlescs00 txt Alessandro Amirante Tobia Castaldi Lorenzo Miniero

draft-miniero-mediactrl-escs-00. txt Alessandro Amirante Tobia Castaldi Lorenzo Miniero Simon Pietro Romano (University of Napoli Federico II) Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

Session Control Protocol (SIP) Control Framework (ESCS/SCFW) Call Flow Examples • This document provides a number of Media Server Control Framework call flows • It is meant as a BCP document conceived to help the development of the framework specification with a practical approach • All the flow scenarios come from direct implementation experience, which can help fix potential drawbacks and/or issues emerging in the protocol 2 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

A Practical Approach • The document embraces a practical approach by providing: – State Diagrams of the framework protocol (both AS and MS perspectives); – Some implementation-oriented considerations that come out of the specification analysis. • Many real-life scenarios are considered in the call flows, and diagrams with different perspectives are included 3 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

Call Flows and Diagrams • Control Channel Establishment • COMEDIA-based negotiation • SYNCH framework transaction • Use Case Scenarios and Examples – Echo Test • Direct Echo Test • Echo Test based on Recording – Phone Call Showed at the demo! • Direct Connection • Conference-based Approach – Conferencing • • Simple Bridging Rich Conference Scenario Coaching Scenario Sidebars – Others? 4 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

CONTROL PENDING CONTROL / - IDLE / TERMINATE API 202 / 202 API 200 / 200 CONTROL RECEIVED API Error / Error API PENDING / REPORT PENDING 200 / - Media Server perspective WAITING FOR LAST 200 API TERMINATE / REPORT TERMINATE UPDATE CONFIRMED PENDING SENT API UPDATE / REPORT UPDATE SENT 200 / - PENDING CONFIRMED API UPDATE / REPORT UPDATE Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007 200 / -

Apllication Server perspective 202 / - CONTROL SENT 202 RECEIVED API CONTROL / send CONTROL REPORT PENDING / send 200 / - IDLE / TERMINATE PENDING Error / Error REPORT TERMINATE / send 200 UPDATE REPORT UPDATE / send 200 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

SIP signalling Steady-state operation Control Framework signalling RTP data University of Napoli Application Server (Wesip) Open. SER SIP messages User Control Channel (High speed binary connector) RTP communication University of Napoli Media Server Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007 7

SIP signalling Control Framework signalling TCP Control channel setup Open. SER University of Napoli Application Server (Wesip) (5) SIP 200 (8) ACK INVITE OK with (3)(2) SIP 100 TRYING with. COMEDIA User Control channel (9)(10) TCPSYNCH connect (11) 200 OK (Dialog-ID, etc. ) (Control Channel) (7)100 ACK (4)(1) SIP TRYING SIP INVITE (6) 200 OK with (2) with COMEDIA University of Napoli Media Server Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007 8

SIP signalling Third Party Call Control (3 PCC) Control Framework signalling RTP data Open. SER University of Napoli Application Server (Wesip) (4) (13) 180 200 Ringing OK (1) SIP (14) INVITE ACK (11) 200 OK (5)(3) (8) (12) INVITE (16) (15) 180 100 200 ACK Ringing ACK Trying (3 PCC) OK (2) SIP INVITE (6)(7) INVITE (3 PCC) (10) (17) 200 ACK OK 100 Trying User RTP media streams flowing (9) SDP negotiation with UAC + tags and labels mapping University of Napoli Media Server Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007 9

SIP signalling Direct Echo example: self connection Control Framework signalling RTP data Open. SER University of Napoli Application Server (Wesip) User RTP media streams flowing The UAC is echoed back everything (1) CONTROL (2) (join UAC to (6) (3) REPORT/TERMINATE REPORT/PENDING (5) (2) 200 202 OK (7) 200 OK itself) (4) “self-join” UAC University of Napoli Media Server Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007 10

Considerations • Is the 202 message really necessary? – Always followed by a REPORT(pending) • Ambiguity between notify/update possible states in REPORT messages • Should notify/update events be possible *after* a terminate? • If only the 200 error code can carry a body, how are package-specific errors notified? • …and others, mostly related to each specific control package – WIP… 11 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007

Discussion • Is the document of interest to the WG? • Are the provided scenarios enough? Are they well described analyzed? • Should security considerations be in the scope of this document, or should they just be referenced from the specification documents? • What else is needed and/or needs to be fixed? 12 Univeristy of Napoli - mediactrl WG, 70 th IETF meeting, Vancouver, Dec. 3 rd 2007