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A PCN encoding using 2 DSCPs to provide 3 or more states

Document Type Expired Internet-Draft (pcn WG)
Expired & archived
Authors Toby Moncaster , Bob Briscoe , Michael Menth
Last updated 2015-10-14 (Latest revision 2012-03-12)
Replaces draft-moncaster-pcn-3-state-encoding
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status Historic
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state Expired (IESG: Dead)
Action Holders
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD David Harrington
IESG note
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


Pre-congestion notification (PCN) is a mechanism designed to protect the Quality of Service of inelastic flows within a controlled domain. It does this by marking packets when traffic load on a link is approaching or has exceeded a threshold below the physical link rate. This experimental encoding scheme specifies how three encoding states can be carried in the IP header using a combination of two DSCPs and the ECN bits. The Basic scheme only allows for three encoding states. The Full scheme provides 6 states, enough for limited end- to-end support for ECN as well.


Toby Moncaster
Bob Briscoe
Michael Menth

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)