RFC 5681 · DRAFT STANDARD · 2009

TCP Congestion Control

Overview

RFC 5681, “TCP Congestion Control”, is a Draft Standard document published in September 2009 by M. Allman, V. Paxson, E. Blanton. It obsoletes RFC 2581. It has since been updated by RFC 9438. The canonical text is published by the RFC Editor.

Abstract

This document defines TCP's four intertwined congestion control algorithms: slow start, congestion avoidance, fast retransmit, and fast recovery. In addition, the document specifies how TCP should begin transmission after a relatively long idle period, as well as discussing various acknowledgment generation methods. This document obsoletes RFC 2581. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Draft Standard” means

A historical maturity level (retired in 2011) that sat between Proposed Standard and Internet Standard and required multiple interoperable implementations.

Read this RFC

The canonical text of RFC 5681 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 2581
Updated by
RFC 9438
Other RFCs from 2009

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