RFC 5696 · PROPOSED STANDARD · 2009

Baseline Encoding and Transport of Pre-Congestion Information

Overview

RFC 5696, “Baseline Encoding and Transport of Pre-Congestion Information”, is a Proposed Standard document published in November 2009 by T. Moncaster, B. Briscoe, M. Menth. It has been obsoleted by RFC 6660 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

The objective of the Pre-Congestion Notification (PCN) architecture is to protect the quality of service (QoS) of inelastic flows within a Diffserv domain. It achieves this by marking packets belonging to PCN-flows when the rate of traffic exceeds certain configured thresholds on links in the domain. These marks can then be evaluated to determine how close the domain is to being congested. This document specifies how such marks are encoded into the IP header by redefining the Explicit Congestion Notification (ECN) codepoints within such domains. The baseline encoding described here provides only two PCN encoding states: Not-marked and PCN-marked. Future extensions to this encoding may be needed in order to provide more than one level of marking severity. [STANDARDS-TRACK]

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

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 5696 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 6660
Other RFCs from 2009

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