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RAI avtcore example 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 RFC 3551, the RTP/AVP profile (and by extension, the profiles that build upon it), to reflect changes in audio codec usage since that document was originally published.

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 there is little reason to use it when much more modern codecs are available. This document updates the recommended audio codec selection for the RTP/AVP profile and removes the SHOULD for DVI4. By extension, this also updates the profiles that build on RTP/AVP, including RTP/SAVP, RTP/AVPF, and RTP/SAVPF.

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 .

The following text of is hereby updated as set forth in : 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.

This document updates the final paragraph of Section 6 of RFC 3551 by replacing "payload types 0 (PCMU) and 5 (DVI4)" with "payload type 0 (PCMU)". We also add a final sentence to that paragraph that states, "Some environments necessitate 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 necessitate support for PCMU.

This document does not introduce any new security considerations for .

Thanks to Colin Perkins for suggesting this update.