RFC 6627 · INFORMATIONAL · 2012

Overview of Pre-Congestion Notification Encoding

Overview

RFC 6627, “Overview of Pre-Congestion Notification Encoding”, is an Informational document published in July 2012 by G. Karagiannis, K. Chan, T. Moncaster, M. Menth, P. Eardley, B. Briscoe. The canonical text is published by the RFC Editor.

Abstract

The objective of Pre-Congestion Notification (PCN) is to protect the quality of service (QoS) of inelastic flows within a Diffserv domain. On every link in the PCN-domain, the overall rate of PCN-traffic is metered, and PCN-packets are appropriately marked when certain configured rates are exceeded. Egress nodes provide decision points with information about the PCN-marks of PCN-packets that allows them to take decisions about whether to admit or block a new flow request, and to terminate some already admitted flows during serious \%pre-congestion.

The PCN working group explored a number of approaches for encoding this pre-congestion information into the IP header. This document provides details of those approaches along with an explanation of the constraints that apply to any solution. This document is not an Internet Standards Track specification; it is published for informational purposes.

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

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

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The canonical text of RFC 6627 is hosted at rfc-editor.org. Available in TXT,HTML.

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