Technical Summary
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 acts as a safety
measure to prevent starvation of network resources denying other
flows from access to the Internet, such measures are essential for an
Internet that is heterogeneous and for traffic that is hard to
predict in advance. 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.
Working Group Summary
The WG has been quite diligent in working on this. There has been
discussion if the specification addresses the right issue, and if the
perimeter behavior it establish is the appropriate one. That consensus
is definitely a rough consensus. A very good number of people have
commented on the specification.
Document Quality
There has been significant input, including simulations both for wired
and wireless networks, the result of these simulations are referenced
by the specification. Simon Perreault at JIVE did a trial deployment in
their service. All of this has helped improving the solution and its
definition significantly and helped verifying the behavior of the
circuit breakers.
Personnel
Magnus Westerlund is the document shepherd.
Responsible AD is Ben Campbell