Internet Engineering Task Force (IETF) H. Kaplan, Ed.
Request for Comments: 6849 Acme Packet
Category: Standards Track K. Hedayat
ISSN: 2070-1721 EXFO
Cisco Systems, Inc.
An Extension to the Session Description Protocol (SDP)
and Real-time Transport Protocol (RTP) for Media Loopback
The wide deployment of Voice over IP (VoIP), real-time text, and
Video over IP services has introduced new challenges in managing and
maintaining real-time voice/text/video quality, reliability, and
overall performance. In particular, media delivery is an area that
needs attention. One method of meeting these challenges is
monitoring the media delivery performance by looping media back to
the transmitter. This is typically referred to as "active
monitoring" of services. 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. Today, in networks that deliver
real-time media, short of running 'ping' and 'traceroute' to the
edge, administrators are left without the necessary tools to actively
monitor, manage, and diagnose quality issues with their service. The
extension defined herein adds new Session Description Protocol (SDP)
media types and attributes that 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.
Kaplan, et al. Standards Track [Page 1]RFC 6849 SDP Media Loopback February 2013Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
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.
This document may contain material from IETF Documents or IETF
Contributions published or made publicly available before November
10, 2008. The person(s) controlling the copyright in some of this
material may not have granted the IETF Trust the right to allow
modifications of such material outside the IETF Standards Process.
Without obtaining an adequate license from the person(s) controlling
the copyright in such materials, this document may not be modified
outside the IETF Standards Process, and derivative works of it may
not be created outside the IETF Standards Process, except to format
it for publication as an RFC or to translate it into languages other
Kaplan, et al. Standards Track [Page 2]RFC 6849 SDP Media Loopback February 2013Table of Contents
1. Introduction ....................................................3
1.1. Use Cases Supported ........................................4
2. Terminology .....................................................6