Coding and congestion control in transport
draft-irtf-nwcrg-coding-and-congestion-00
NWCRG N. Kuhn, Ed.
Internet-Draft CNES
Intended status: Informational E. Lochin
Expires: June 7, 2020 ISAE-SUPAERO
F. Michel
UCLouvain
M. Welzl
University of Oslo
December 5, 2019
Coding and congestion control in transport
draft-irtf-nwcrg-coding-and-congestion-00
Abstract
This document discusses the interaction between congestion control
and coding mechanism at the transport layer. The scope of the
document is end-to-end communications. Examples of interest for the
proposed solution is to better deal with tail losses or with networks
with non-congestion losses. Coding for tunnels is out-of-the scope
of the document.
Status of This Memo
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This Internet-Draft will expire on June 7, 2020.
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Internet-Draft Coding and congestion December 2019
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Separate channels . . . . . . . . . . . . . . . . . . . . . . 3
3. Base solution description . . . . . . . . . . . . . . . . . . 3
4. Server-side coding solutions . . . . . . . . . . . . . . . . 4
4.1. Coded packets without considering CWND progression . . . 4
4.2. Coded packets driven by CWND progression . . . . . . . . 4
5. Server-side reaction to recovered packet signals . . . . . . 4
5.1. The server congestion control considers recovered packet
signals as congestion-implied packet losses . . . . . . . 5
5.2. The server adapts its window reduction to recovered
packet signals . . . . . . . . . . . . . . . . . . . . . 5
5.3. The server ignores recovered packet signals . . . . . . . 5
6. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
9. Security Considerations . . . . . . . . . . . . . . . . . . . 7
10. Informative References . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
There are cases where deploying coding improves the quality of the
transmission. As example, the server may hardly detect tail losses
that impact may impact the application layer. Another example may be
the networks where non-congestion losses are persistent and prevent
the server from exploiting the link capacity. [RFC5681] defines TCP
as a loss-based congestion control and coding mechanisms can hide
congestion signals to the server. This memo discusses simple best
practices on how coding and congestion control mechanisms could
coexist.
The proposed recommendations apply for coding at the transport or
application layer and coding for tunnels is out-of-the scope of the
document.
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2. Separate channels
Figure 1 presents the notations that will be used in this document
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