Subject: New draft on 'SDP extensions for Quality of Service'

From: [email-masked]
Date: Thu, 15 Nov 2001 17:56:26 +0100

Hello,

Please find attached a new draft on the topic of 'SDP extensions for
Quality of Service' that we intend to present to the MMUSIC WG at IETF
#52. Your comments are most welcome.

This document describes a framework to negotiate end-to-end the
"Quality" of a multimedia session "as the end-user wants to perceive
it". This UPQoS (User Perceived QoS) negotiation is achieved at session
signaling level using two types of new SDP extensions, which this
document proposes to specify. All session control elements - user agents
as well as proxies - involved in the multimedia session setup may
participate to the UPQoS negotiation.   
                   
Secondly this document proposes to specify SDP extensions which allow to
express the UPQoS level per medium stream during the UPQoS negotiation.
The first type of SDP extensions characterizes the traffic type of the
bearer associated with the medium stream. The second
tolerance/sensitivity level of the service requested by the end-user
with respect to the QoS information carried in the first type of SDP
extensions. 

It is important to note that this draft only proposes to specify some
SDP extensions. The draft does not propose any modifications to existing
session signalling protocols (e.g. SIP protocol). It reuses the current
SIP procedures for the session description negotiation. Secondly the
draft does not propose any changes to existing bearer setup mechanisms
(e.g. RSVP, Diffserv, MPLS) either. The concepts proposed in the draft
are simply complementary to existing bearer setup specifications.

Lieve Bos