Subject: [AVTCORE] I-D Action: draft-ietf-avtcore-rtp-circuit-breakers-11.txt

From: [email-masked]
Date: Fri, 16 Oct 2015 09:30:08 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.
 This draft is a work item of the Audio/Video Transport Core Maintenance Working Group of the IETF.

        Title           : Multimedia Congestion Control: Circuit Breakers for Unicast RTP Sessions
        Authors         : Colin Perkins
                          Varun Singh
	Filename        : draft-ietf-avtcore-rtp-circuit-breakers-11.txt
	Pages           : 23
	Date            : 2015-10-16

Abstract:
   The Real-time Transport Protocol (RTP) is widely used in telephony,
   video conferencing, and telepresence applications.  Such applications
   are often run on best-effort UDP/IP networks.  If congestion control
   is not implemented in the applications, then network congestion will
   deteriorate the user's multimedia experience.  This document does not
   propose a congestion control algorithm; instead, it defines a minimal
   set of RTP circuit-breakers.  Circuit-breakers are conditions under
   which an RTP sender needs to stop transmitting media data in order to
   protect the network from excessive congestion.  It is expected that,
   in the absence of severe congestion, all RTP applications running on
   best-effort IP networks will be able to run without triggering these
   circuit breakers.  Any future RTP congestion control specification
   will be expected to operate within the constraints defined by these
   circuit breakers.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-avtcore-rtp-circuit-breakers/

There's also a htmlized version available at:
https://tools.ietf.org/html/draft-ietf-avtcore-rtp-circuit-breakers-11

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-avtcore-rtp-circuit-breakers-11

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

---

From: Colin Perkins <[email-masked]>
Date: Mon, 19 Oct 2015 11:17:26 +0100

> On 16 Oct 2015, at 17:30, [email-masked] wrote:
> 
> 

This version of the draft is a major update, that makes the following changes:

- Update the media timeout circuit breaker to address the over- and under-sampling issues raised by Magnus Westerlund, by taking into account the RTT and RTP framing interval in the calculation, as well as the RTCP reporting interval.

- Update the congestion circuit breaker to address the over- and under-sampling issues raised by Magnus Westerlund, and to account for codecs that cannot change their rate on each frame, by modifying the definition of CB_INTERVAL to include the RTP framing interval, the frame group size, and the RTT in the calculation, as well as the RTCP reporting interval.

- Collect definitions and clarify terminology.

- Clarify behaviour when interworking with systems that don’t implement RTCP, based on feedback by Simon Perreault.

- Remove discussion on Impact of RTCP Reporting Groups, that seemed to confuse rather than clarify.

- Various editorial fixes to address other review comments by Simon Perreault, and make assorted other corrections. 

Feedback welcome. 

Colin

-- 
Colin Perkins
https://csperkins.org/

---

From: Magnus Westerlund <[email-masked]>
Date: Tue, 20 Oct 2015 13:08:48 +0200

WG,

I want to stress that I personally think this looks pretty well baked 
and my high level issues are resolved. I also think what is in this 
document is actually implementable, however that is without having 
implemented.

I really want to encourage that you review this now!

Cheers

Magnus Westerlund
AVTCORE chair

-- 

Magnus Westerlund

----------------------------------------------------------------------
Services, Media and Network features, Ericsson Research EAB/TXM
----------------------------------------------------------------------
Ericsson AB                 | Phone  +46 10 7148287
Färögatan 6                 | Mobile +46 73 0949079
SE-164 80 Stockholm, Sweden | mailto: [email-masked]
----------------------------------------------------------------------