The Some Congestion Experienced ECN Codepoint
draft-morton-tsvwg-sce-02

Document Type Active Internet-Draft (individual)
Authors Jonathan Morton  , Peter Heist  , Rodney Grimes 
Last updated 2020-11-02
Replaces draft-morton-taht-tsvwg-sce
Stream (None)
Intended RFC status (None)
Formats plain text html xml pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
Transport Working Group                                        J. Morton
Internet-Draft                                                          
Updates: 3168, 8311 (if approved)                               P. Heist
Intended status: Experimental                                           
Expires: 6 May 2021                                     R.W. Grimes, Ed.
                                                         2 November 2020

             The Some Congestion Experienced ECN Codepoint
                       draft-morton-tsvwg-sce-02

Abstract

   This memo reclassifies ECT(1) to be an early notification of
   congestion on ECT(0) marked packets, which can be used by AQM
   algorithms and transports as an earlier signal of congestion than CE.
   It is a simple, transparent, and backward compatible upgrade to
   existing IETF-approved AQMs, RFC3168, and nearly all congestion
   control algorithms.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 6 May 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

Morton, et al.             Expires 6 May 2021                   [Page 1]
Internet-Draft                    sceb                     November 2020

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Background  . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  Some Congestion Experienced . . . . . . . . . . . . . . . . .   5
   5.  Design Rationale  . . . . . . . . . . . . . . . . . . . . . .   7
     5.1.  Risks with ECN Signaling  . . . . . . . . . . . . . . . .   7
     5.2.  Unresponsive Flows  . . . . . . . . . . . . . . . . . . .   8
     5.3.  Fairness  . . . . . . . . . . . . . . . . . . . . . . . .   9
     5.4.  ECT(1) as SCE . . . . . . . . . . . . . . . . . . . . . .   9
   6.  Diffserv Usage  . . . . . . . . . . . . . . . . . . . . . . .  10
     6.1.  SCE Diffserv Codepoints (DSCPs) . . . . . . . . . . . . .  10
       6.1.1.  SCE-CAPABLE . . . . . . . . . . . . . . . . . . . . .  10
       6.1.2.  SCE-LOWDELAY  . . . . . . . . . . . . . . . . . . . .  11
       6.1.3.  SCE-LOWCOST . . . . . . . . . . . . . . . . . . . . .  11
     6.2.  Diffserv Codepoints for Experimental and Private Use  . .  11
     6.3.  Diffserv Codepoints for Public Use  . . . . . . . . . . .  12
   7.  Examples of use . . . . . . . . . . . . . . . . . . . . . . .  12
     7.1.  Codel-type AQMs . . . . . . . . . . . . . . . . . . . . .  12
     7.2.  RED-type AQMs (including PIE) . . . . . . . . . . . . . .  13
     7.3.  Simple Two-Queue Middleboxes  . . . . . . . . . . . . . .  13
     7.4.  TCP . . . . . . . . . . . . . . . . . . . . . . . . . . .  14
     7.5.  Other . . . . . . . . . . . . . . . . . . . . . . . . . .  14
   8.  Compatibility . . . . . . . . . . . . . . . . . . . . . . . .  14
     8.1.  Existing ECN & AQM Deployments  . . . . . . . . . . . . .  14
     8.2.  L4S . . . . . . . . . . . . . . . . . . . . . . . . . . .  15
   9.  Ongoing Research and Development  . . . . . . . . . . . . . .  16
   10. Related Work  . . . . . . . . . . . . . . . . . . . . . . . .  16
   11. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16
   12. Security Considerations . . . . . . . . . . . . . . . . . . .  17
   13. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  17
   14. Normative References  . . . . . . . . . . . . . . . . . . . .  17
   15. Informative References  . . . . . . . . . . . . . . . . . . .  17
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  21

Morton, et al.             Expires 6 May 2021                   [Page 2]
Show full document text