Microsoft's Datacenter TCP (DCTCP): TCP Congestion Control for Datacenters

The information below is for an old version of the document
Document Type Expired Internet-Draft (individual in tsv area)
Authors Stephen Bensley  , Lars Eggert  , Dave Thaler 
Last updated 2014-12-07 (latest revision 2014-06-05)
Replaced by RFC 8257, RFC 8257
Stream IETF
Intended RFC status Informational
Expired & archived
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Stream WG state (None)
Document shepherd No shepherd assigned
IESG IESG state Expired (IESG: Dead)
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Responsible AD Martin Stiemerling
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


This memo describes Datacenter TCP (DCTCP), an improvement to TCP congestion control for datacenter traffic, as implemented in Windows Server 2012. DCTCP enhances Explicit Congestion Notification (ECN) processing to estimate the fraction of bytes that encounter congestion, rather than simply detecting that some congestion has occurred. DCTCP then scales the TCP congestion window based on this estimate. This method achieves high burst tolerance, low latency, and high throughput with shallow-buffered switches.


Stephen Bensley (
Lars Eggert (
Dave Thaler (

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