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Re: congestion control? - (was Re: Appointment of a Transport Area Director)

Brian E Carpenter <brian.e.carpenter@gmail.com> Tue, 05 March 2013 14:16 UTC

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Message-ID: <5135FE1F.3030308@gmail.com>
Date: Tue, 05 Mar 2013 14:15:59 +0000
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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To: "Dearlove, Christopher (UK)" <Chris.Dearlove@baesystems.com>
Subject: Re: congestion control? - (was Re: Appointment of a Transport Area Director)
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On 05/03/2013 11:55, Dearlove, Christopher (UK) wrote:
> I've no idea about the example quoted, but I can see some of their motivation.
> 
> TCP's assumptions (really simplified) that loss of packet = congestion => backoff
> aren't necessarily so in a wireless network, where packets can be lost without
> congestion. This means that TCP into, out of, or across, a MANET using TCP can be
> bad. It then tends to happen that the MANET people don't fully understand TCP,
> and the TCP people don't fully understand MANETs.

The effects you mention were definitely discussed in PILC.
http://www.ietf.org/wg/concluded/pilc.html
Maybe the PILC documents need revision?

    Brian

> 
> I don't have a single good reference for what I say above, in particular have
> things got better (or worse) as TCP evolves, and therefore which references
> are still valid? But the obvious Google search (TCP MANET) throws up various
> discussions.
>

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