Controlled Delay Active Queue Management

The information below is for an old version of the document
Document Type Expired Internet-Draft (individual in tsv area)
Last updated 2013-01-10 (latest revision 2012-07-09)
Replaced by rfc8289, draft-ietf-aqm-codel, draft-aqm-codel
Stream IETF
Intended RFC status Informational
Expired & archived
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Stream WG state (None)
Document shepherd None
IESG IESG state Expired (IESG: Dead)
Consensus Boilerplate Unknown
Telechat date
Responsible AD Wesley Eddy
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


The "persistently full buffer" problem has been discussed in the IETF community since the early 80's [RFC896]. The IRTF's End-to-End Working Group called for the deployment of active queue management to solve the problem in 1998 [RFC2309]. Despite the awareness and recommendations, the "full buffer" problem has not gone away, but on the contrary has become worse as buffers have grown in size and proliferated and today's networks proved intractable for available AQM approaches. The overall problem is presently known as "bufferbloat" [TSVBB2011, BB2011] and has become increasingly important, particularly at the consumer edge. This document describes a recently developed AQM, Controlled Delay (CoDel) algorithm, which was designed to work in modern networking environments and can be deployed as a major part of the solution to bufferbloat [CODEL2012].


Kathleen Nichols (

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