RFC 4138 · EXPERIMENTAL · 2005

Forward RTO-Recovery : An Algorithm for Detecting Spurious Retransmission Timeouts with TCP and the Stream Control Transmission Protocol

Overview

RFC 4138, “Forward RTO-Recovery : An Algorithm for Detecting Spurious Retransmission Timeouts with TCP and the Stream Control Transmission Protocol”, is an Experimental document published in August 2005 by P. Sarolahti, M. Kojo. It has since been updated by RFC 5682. The canonical text is published by the RFC Editor.

Abstract

Spurious retransmission timeouts cause suboptimal TCP performance because they often result in unnecessary retransmission of the last window of data. This document describes the F-RTO detection algorithm for detecting spurious TCP retransmission timeouts. F-RTO is a TCP sender-only algorithm that does not require any TCP options to operate. After retransmitting the first unacknowledged segment triggered by a timeout, the F-RTO algorithm of the TCP sender monitors the incoming acknowledgments to determine whether the timeout was spurious. It then decides whether to send new segments or retransmit unacknowledged segments. The algorithm effectively helps to avoid additional unnecessary retransmissions and thereby improves TCP performance in the case of a spurious timeout. The F-RTO algorithm can also be applied to the Stream Control Transmission Protocol (SCTP). This memo defines an Experimental Protocol for the Internet community.

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

What “Experimental” means

Describes a specification that is part of a research or development effort, published so the community can gain experience with it.

Read this RFC

The canonical text of RFC 4138 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Updated by
RFC 5682
Other RFCs from 2005

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