The IESG has approved the following document: - 'An Extension to the Session Description Protocol (SDP) and Real-time Transport Protocol (RTP) for Media Loopback' (draft-ietf-mmusic-media-loopback-27.txt) as Proposed Standard This document is the product of the Multiparty Multimedia Session Control Working Group. The IESG contact persons are Gonzalo Camarillo and Robert Sparks. A URL of this Internet Draft is: http://datatracker.ietf.org/doc/draft-ietf-mmusic-media-loopback/ Technical Summary This document provides extensions to the Session Description Protocol (SDP) and the Real-time Transport Protocol (RTP) for enabling looping of sent media. Media loopback is especially popular in ensuring the quality of transport to the edge of a given VoIP, Real-time Text or Video over IP service. The extension defined herein adds new SDP media types and attributes, which enable establishment of media sessions where the media is looped back to the transmitter. Such media sessions will serve as monitoring and troubleshooting tools by providing the means for measurement of more advanced VoIP, Real-time Text and Video over IP performance metrics. Working Group Summary The first version of the document was available at the end of 2004. Since that time, the working group has been discussing a number of issues toward getting the consensus that is believed to be achieved in version 22. The description of a latching mechanism to traverse NATs and firewalls was discussed and decided to be removed from the actual document in favor of standard NAT traversal techniques such as ICE/STUN/TURN. Document Quality At least four implementations of this functionality are known. Four other vendors have indicated they plan to implement it. The document was WGLCed on version 16. Additionally, the PAYLOAD WG also conducted a thorough review of the same 16 version. As a result of these reviews, 34 changes were requested by, among others, Tolga Asveren, Dan Wing, Emil Ivov, Flemming Andreasen, and Miguel A. Garcia. These comments were subsequently introduced into versions 17 and 18. A new WGLC was issued on version 18, bringing a new set of comments by Flemming Andreasen, Magnus Westerlund, and Gunnar Hellstrom. These were addressed in version 19. At least Magnus Westerlund and Flemming Andreasen did a thorough review of the document as part of the WGLC on version 18. Version 18 was sent to the ietf-types mailing list for review on April 4, 2012. Bjorern Hoehrmann and Magnus Westerlund posted comments that were addressed in version 19. Personnel Who is the Document Shepherd? Who is the Responsible Area Director? Miguel A. Garcia is the Document Shepherd. Gonzalo Camarillo is the Responsible Area Director
