RFC 2736 (rfc2736) - Page 1 of 10
Guidelines for Writers of RTP Payload Format Specifications
Alternative Format: Original Text Document
Network Working Group M. Handley
Request for Comments: 2736 ACIRI
BCP: 36 C. Perkins
Category: Best Current Practice UCL
December 1999
Guidelines for Writers of RTP Payload Format Specifications
Status of this Memo
This document specifies an Internet Best Current Practices for the
Internet Community, and requests discussion and suggestions for
improvements. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1999). All Rights Reserved.
Abstract
This document provides general guidelines aimed at assisting the
authors of RTP Payload Format specifications in deciding on good
formats. These guidelines attempt to capture some of the experience
gained with RTP as it evolved during its development.
1. Introduction
This document provides general guidelines aimed at assisting the
authors of RTP [9] Payload Format specifications in deciding on good
formats. These guidelines attempt to capture some of the experience
gained with RTP as it evolved during its development.
The principles outlined in this document are applicable to almost all
data types, but are framed in examples of audio and video codecs for
clarity.
2. Background
RTP was designed around the concept of Application Level Framing
(ALF), first described by Clark and Tennenhouse [2]. The key argument
underlying ALF is that there are many different ways an application
might be able to cope with misordered or lost packets. These range
from ignoring the loss, to re-sending the missing data (either from a
buffer or by regenerating it), and to sending new data which
supersedes the missing data. The application only has this choice if
the transport protocol is dealing with data in "Application Data
Units" (ADUs). An ADU contains data that can be processed out-of-
Handley & Perkins Best Current Practice