Subject: [multipathtcp] Last Call: <draft-ietf-mptcp-congestion-05.txt> (Coupled Congestion Control for Multipath Transport Protocols) to Experimental RFC

From: The IESG <[email-masked]>
Date: Tue, 21 Jun 2011 06:31:50 -0700

The IESG has received a request from the Multipath TCP WG (mptcp) to
consider the following document:
- 'Coupled Congestion Control for Multipath Transport Protocols'
  <draft-ietf-mptcp-congestion-05.txt> as an Experimental RFC

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
[email-masked] mailing lists by 2011-07-05. Exceptionally, comments may be
sent to [email-masked] instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract

   Often endpoints are connected by multiple paths, but communications
   are usually restricted to a single path per connection.  Resource
   usage within the network would be more efficient were it possible for
   these multiple paths to be used concurrently.  Multipath TCP is a
   proposal to achieve multipath transport in TCP.

   New congestion control algorithms are needed for multipath transport
   protocols such as Multipath TCP, as single path algorithms have a
   series of issues in the multipath context.  One of the prominent
   problems is that running existing algorithms such as standard TCP
   independently on each path would give the multipath flow more than
   its fair share at a bottleneck link traversed by more than one of its
   subflows.  Further, it is desirable that a source with multiple paths
   available will transfer more traffic using the least congested of the
   paths, hence achieving resource pooling.  This would increase the
   overall efficiency of the network and also its robustness to failure.

   This document presents a congestion control algorithm which couples
   the congestion control algorithms running on different subflows by
   linking their increase functions, and dynamically controls the
   overall aggressiveness of the multipath flow.  The result is a
   practical algorithm that is fair to TCP at bottlenecks while moving
   traffic away from congested links.

The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-mptcp-congestion/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-mptcp-congestion/

No IPR declarations have been submitted directly on this I-D.