Guidelines for Choosing RTP Control Protocol (RTCP) Canonical Names (CNAMEs)
draft-ietf-avtcore-6222bis-02

The information below is for an old version of the document
Document Type Active Internet-Draft (avtcore WG)
Last updated 2013-04-13
Replaces draft-rescorla-avtcore-6222bis
Stream IETF
Intended RFC status (None)
Formats plain text pdf html bibtex
Reviews
Stream WG state In WG Last Call
Document shepherd Magnus Westerlund
IESG IESG state I-D Exists
Consensus Boilerplate Unknown
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                           A. Begen
Internet-Draft                                                     Cisco
Obsoletes: 6222 (if approved)                                 C. Perkins
Intended status: Standards Track                   University of Glasgow
Expires: October 15, 2013                                        D. Wing
                                                                   Cisco
                                                             E. Rescorla
                                                              RTFM, Inc.
                                                          April 13, 2013

          Guidelines for Choosing RTP Control Protocol (RTCP)
                        Canonical Names (CNAMEs)
                     draft-ietf-avtcore-6222bis-02

Abstract

   The RTP Control Protocol (RTCP) Canonical Name (CNAME) is a
   persistent transport-level identifier for an RTP endpoint.  While the
   Synchronization Source (SSRC) identifier of an RTP endpoint may
   change if a collision is detected or when the RTP application is
   restarted, its RTCP CNAME is meant to stay unchanged, so that RTP
   endpoints can be uniquely identified and associated with their RTP
   media streams.

   For proper functionality, RTCP CNAMEs should be unique within the
   participants of an RTP session.  However, the existing guidelines for
   choosing the RTCP CNAME provided in the RTP standard are insufficient
   to achieve this uniqueness.  RFC 6222 was published to update those
   guidelines to allow endpoints to choose unique RTCP CNAMEs.
   Unfortunately, later investigations showed that some parts of the new
   algorithms were unnecessarily complicated and/or ineffective.  This
   document addresses these concerns and replaces RFC 6222.

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."

Begen, et al.           Expires October 15, 2013                [Page 1]
Internet-Draft           Choosing an RTCP CNAME               April 2013

   This Internet-Draft will expire on October 15, 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
   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.  Requirements Notation . . . . . . . . . . . . . . . . . . . .   3
   3.  Deficiencies with Earlier Guidelines for Choosing an RTCP
       CNAME . . . . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Choosing an RTCP CNAME  . . . . . . . . . . . . . . . . . . .   4
     4.1.  Persistent RTCP CNAMEs versus Per-Session RTCP CNAMEs . .   4
     4.2.  Requirements  . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Procedure to Generate a Unique Identifier . . . . . . . . . .   6
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
     6.1.  Considerations on Uniqueness of RTCP CNAMEs . . . . . . .   7
     6.2.  Session Correlation Based on RTCP CNAMEs  . . . . . . . .   7
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   8
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   9

1.  Introduction

   In Section 6.5.1 of the RTP specification, [RFC3550], there are a
   number of recommendations for choosing a unique RTCP CNAME for an RTP
   endpoint.  However, in practice, some of these methods are not
   guaranteed to produce a unique RTCP CNAME.  [RFC6222] updated the
   guidelines for choosing RTCP CNAMEs, superseding those presented in
Show full document text