Subject: [AVTCORE] New Packet formats section in Multipath RTP (draft-singh-avtcore-mprtp-01)

From: varun singh <[email-masked]>
Date: Mon, 14 Mar 2011 23:57:10 +0200

Greetings,

We have updated the draft and the latest iteration contains an updated
section on Packet Formats (Section 9). In Section 9.3.1, we define a
generic mechanism to reuse the session level reports (e.g., SR, RR,
XR) for subflow-specific reports. An example non-compound subflow
MPRTCP is shown in Figure 12.

For exact changes see
http://tools.ietf.org/rfcdiff?url2=draft-singh-avtcore-mprtp-01.txt.

The draft contains some open issues (and some recommendations) that
should be discussed here on the mailing so that we can move ahead and
close them.

Regards,
Varun

Begin forwarded message:

A new version of I-D, draft-singh-avtcore-mprtp-01.txt has been
successfully submitted by Varun Singh and posted to the IETF
repository.

Filename:	 draft-singh-avtcore-mprtp
Revision:	 01
Title:		 Multipath RTP (MPRTP)
Creation_date:	 2011-03-14
WG ID:		 Independent Submission
Number_of_pages: 29

Abstract:
The Real-time Transport Protocol (RTP) is used to deliver real-time
content and, along with the RTP Control Protocol (RTCP), forms the
control channel between the sender and receiver.  However, RTP and
RTCP assume a single delivery path between the sender and receiver
and make decisions based on the measured characteristics of this
single path.  Increasingly, endpoints are becoming multi-homed, which
means that they are connected via multiple Internet paths.  Network
utilization can be improved when endpoints use multiple parallel
paths for communication.  The resulting increase in reliability and
throughput can also enhance the user experience.  This document
extends the Real-time Transport Protocol (RTP) so that a single
session can take advantage of the availability of multiple paths
between two endpoints.

The IETF Secretariat.

Varun Singh
http://www.netlab.tkk.fi/~varun

---

From: Roni Even <[email-masked]>
Date: Wed, 16 Mar 2011 16:34:20 +0200

Hi,
I noticed that in the document you talk about RTCP header extension (section
8.1, 9.1) yet it looks to me like you define a new RTCP packet type and not
an extension to RTCP SR or RR. Please clarify and if you define new packets
it will be better to use one RTCP packet type.

Regards
Roni Even

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On Behalf Of
> varun singh
> Sent: Monday, March 14, 2011 11:57 PM
> To: [email-masked]
> Subject: [AVTCORE] New Packet formats section in Multipath RTP (draft-
> singh-avtcore-mprtp-01)
> 
> Greetings,
> 
> _______________________________________________
> Audio/Video Transport Core Maintenance
> [email-masked]
> https://www.ietf.org/mailman/listinfo/avt

---

From: varun singh <[email-masked]>
Date: Fri, 18 Mar 2011 13:43:26 +0200

Hi Roni,

> 8.1, 9.1) yet it looks to me like you define a new RTCP packet type and not

We mean the latter, MPRTP requires new RTCP packet types.

> it will be better to use one RTCP packet type.

We will make alterations to the packet formats to reduce it to using
one RTCP packet type.
An alternative to a new RTCP packet type would be to define these RTCP
packets as App Packets (PT=204). However, I don't think MPRTP fits the
definition of Application defined packet.

Additionally, I'm also looking for comments on the packet format
defined in 9.3 (if reusing and re-encapsulating other RTCP packet
types) is a good idea or not.