avtcore T.B. Terriberry Internet-Draft Mozilla Corporation Updates: 3551 (if approved) April 10, 2013 Intended status: Standards Track Expires: October 12, 2013 Update to Recommended Codecs for the RTP Profile for Audio and Video Conferences with Minimal Control (RTP/AVP) draft-ietf-avtcore-avp-codecs-02 Abstract The RTP Profile for Audio and Video Conferences with Minimal Control (RTP/AVP) is the basis for many other profiles, such as the Secure Real-time Transport Protocol (RTP/SAVP), the Extended RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/ AVPF), and the Extended Secure RTP Profile for RTCP-Based Feedback (RTP/SAVPF). This document updates the RTP/AVP profile (and by extension, the profiles that build upon it) to reflect changes in audio codec usage since the document was originally published. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on October 12, 2013. Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents Terriberry Expires October 12, 2013 [Page 1]
Internet-Draft RTP/AVP Codecs April 2013 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Updates to RFC 3551 . . . . . . . . . . . . . . . . . . . . . 2 3.1. Updates to Section 6 . . . . . . . . . . . . . . . . . . 2 4. Security Considerations . . . . . . . . . . . . . . . . . . . 3 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 3 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 3 7.1. Normative References . . . . . . . . . . . . . . . . . . 3 7.2. Informative References . . . . . . . . . . . . . . . . . 3 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction [RFC3551] says that audio applications operating under the RTP/AVP profile SHOULD be able to send and receive PCMU and DVI4. However, in practice, many RTP deployments do not support DVI4, and its utility is limited in the presence of much more modern codecs. This document updates the recommended audio codec selection for the RTP/ AVP profile to remove the SHOULD for DVI4. By extension, this also updates the profiles which build on RTP/AVP, including RTP/SAVP [RFC3711], RTP/AVPF [RFC4585], and RTP/SAVPF [RFC5124]. 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. Updates to RFC 3551 The following text of [RFC3551] is hereby updated as set forth below in Section 3.1. Audio applications operating under this profile SHOULD, at a minimum, be able to send and/or receive payload types 0 (PCMU) and 5 (DVI4). This allows interoperability without format negotiation and ensures successful negotiation with a conference control protocol. 3.1. Updates to Section 6 Terriberry Expires October 12, 2013 [Page 2]
Internet-Draft RTP/AVP Codecs April 2013 In the final paragraph of Section 6, replace, "payload types 0 (PCMU) and 5 (DVI4)," with "payload type 0 (PCMU)." Also, add a final sentence to this paragraph that states, "Some environments REQUIRE support for PCMU." This results in the following paragraph: Audio applications operating under this profile SHOULD, at a minimum, be able to send and/or receive payload type 0 (PCMU). This allows interoperability without format negotiation and ensures successful negotiation with a conference control protocol. Some environments REQUIRE support for PCMU. 4. Security Considerations This document does not introduce any new security considerations for [RFC3551]. 5. IANA Considerations This document has no actions for IANA. 6. Acknowledgments Thanks to Colin Perkins for suggesting this update. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3551] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and Video Conferences with Minimal Control", STD 65, RFC 3551, July 2003. 7.2. Informative References [RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. Norrman, "The Secure Real-time Transport Protocol (SRTP)", RFC 3711, March 2004. [RFC4585] Ott, J., Wenger, S., Sato, N., Burmeister, C., and J. Rey, "Extended RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/AVPF)", RFC 4585, July 2006. Terriberry Expires October 12, 2013 [Page 3]
Internet-Draft RTP/AVP Codecs April 2013 [RFC5124] Ott, J. and E. Carrara, "Extended Secure RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/SAVPF)", RFC 5124, February 2008. Author's Address Timothy B. Terriberry Mozilla Corporation 650 Castro Street Mountain View, CA 94041 USA Phone: +1 650 903-0800 Email: tterribe@xiph.org Terriberry Expires October 12, 2013 [Page 4]
