Subject: [tsvwg] I-D Action: draft-ietf-tsvwg-ecn-l4s-id-10.txt

From: [email-masked]
Date: Mon, 09 Mar 2020 16:44:13 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the Transport Area Working Group WG of the IETF.

        Title           : Identifying Modified Explicit Congestion Notification (ECN) Semantics for Ultra-Low Queuing Delay (L4S)
        Authors         : Koen De Schepper
                          Bob Briscoe
	Filename        : draft-ietf-tsvwg-ecn-l4s-id-10.txt
	Pages           : 45
	Date            : 2020-03-09

Abstract:
   This specification defines the identifier to be used on IP packets
   for a new network service called low latency, low loss and scalable
   throughput (L4S).  It is similar to the original (or 'Classic')
   Explicit Congestion Notification (ECN).  'Classic' ECN marking was
   required to be equivalent to a drop, both when applied in the network
   and when responded to by a transport.  Unlike 'Classic' ECN marking,
   for packets carrying the L4S identifier, the network applies marking
   more immediately and more aggressively than drop, and the transport
   response to each mark is reduced and smoothed relative to that for
   drop.  The two changes counterbalance each other so that the
   throughput of an L4S flow will be roughly the same as a non-L4S flow
   under the same conditions.  Nonetheless, the much more frequent
   control signals and the finer responses to them result in much more
   fine-grained adjustments, so that ultra-low and consistently low
   queuing delay (typically sub-millisecond on average) becomes possible
   for L4S traffic without compromising link utilization.  Thus even
   capacity-seeking (TCP-like) traffic can have high bandwidth and very
   low delay at the same time, even during periods of high traffic load.

   The L4S identifier defined in this document distinguishes L4S from
   'Classic' (e.g.  TCP-Reno-friendly) traffic.  It gives an incremental
   migration path so that suitably modified network bottlenecks can
   distinguish and isolate existing traffic that still follows the
   Classic behaviour, to prevent it degrading the low queuing delay and
   loss of L4S traffic.  This specification defines the rules that L4S
   transports and network elements need to follow to ensure they neither
   harm each other's performance nor that of Classic traffic.  Examples
   of new active queue management (AQM) marking algorithms and examples
   of new transports (whether TCP-like or real-time) are specified
   separately.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-tsvwg-ecn-l4s-id/

There are also htmlized versions available at:
https://tools.ietf.org/html/draft-ietf-tsvwg-ecn-l4s-id-10
https://datatracker.ietf.org/doc/html/draft-ietf-tsvwg-ecn-l4s-id-10

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-tsvwg-ecn-l4s-id-10

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/