Proportional Rate Reduction (PRR)

Metadata

Publisher: IETF
Doc Type: Standard
Pages: 20
Abstract: This document specifies a Standards Track version of the Proportional Rate Reduction (PRR) algorithm that obsoletes the Experimental version described in RFC 6937. PRR regulates the amount of data sent by TCP or other transport protocols during fast recovery. PRR accurately regulates the actual flight size through recovery such that at the end of recovery it will be as close as possible to the slow start threshold (ssthresh), as determined by the congestion control algorithm.
Publication Date: 2025-12-01
Status Note: Proposed Standard
DOI: 10.17487/RFC9937
Link: https://doi.org/10.17487/RFC9937
Author(s): Matt Mathis
Neal Cardwell
Yuchung Cheng
Nandita Dukkipati
Keyword(s): Loss Recovery, SACK, Self Clock, Fast Retransmit, Fast Recovery

Latest version of IETF RFC 9937

Document Versions — IETF RFC 9937

▶ IETF RFC 9937 (2025-12-01)

THIS DOC [ACTIVE] [LATEST VERSION]

Normative Reference(s)

IETF RFC 1191 [Active*]
IETF RFC 2018 [Active*]
IETF RFC 2119 [Active*]
IETF RFC 4821 [Active*]
IETF RFC 5681 [Active*]
IETF RFC 6582 [Active*]
IETF RFC 6675 [Active*]
IETF RFC 8174 [Active*]
IETF RFC 8201 [Active*]
RFC8985 — RFC8985 EXTERNAL
IETF RFC 9293 [Active*]
IETF RFC 9438 [Active*]

Bibliographic Reference(s)

10.1145-52325.52356 — Jacobson88 EXTERNAL
10.1145-248156.248180 — Hoe96Startup EXTERNAL
10.1145-248156.248181 — FACK EXTERNAL
10.1145-505696.505704 — Savage99 EXTERNAL
10.1145-2068816.2068832 — IMC11 EXTERNAL
10.1145-2934872.2934873 — Flach2016policing EXTERNAL
IETF.draft-mathis-tcp-ratehalving-00 — I-D.mathis-tcp-ratehalving EXTERNAL
IETF.draft-welzl-iccrg-pacing-03 — I-D.welzl-iccrg-pacing EXTERNAL
"Proportional Rate Reduction for TCP.", commit a262f0cdf1f2916ea918dc329492abb5323d9a6c, August 2011, <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a262f0cdf1f2916ea918dc329492abb5323d9a6c>. EXTERNAL
IETF RFC 3042 [Active*]
IETF RFC 3168 [Active*]
IETF RFC 3517 [Superseded*]
IETF RFC 6937 [Superseded*]
RFC9743 — RFC9743 EXTERNAL

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doi: 10.17487/RFC9937
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