RFC 3522 · EXPERIMENTAL · 2003

The Eifel Detection Algorithm for TCP

Overview

RFC 3522, “The Eifel Detection Algorithm for TCP”, is an Experimental document published in April 2003 by R. Ludwig, M. Meyer. The canonical text is published by the RFC Editor.

Abstract

The Eifel detection algorithm allows a TCP sender to detect a posteriori whether it has entered loss recovery unnecessarily. It requires that the TCP Timestamps option defined in RFC 1323 be enabled for a connection. The Eifel detection algorithm makes use of the fact that the TCP Timestamps option eliminates the retransmission ambiguity in TCP. Based on the timestamp of the first acceptable ACK that arrives during loss recovery, it decides whether loss recovery was entered unnecessarily. The Eifel detection algorithm provides a basis for future TCP enhancements. This includes response algorithms to back out of loss recovery by restoring a TCP sender's congestion control state. 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.

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