Re: [re-ECN] VIability issue #2

João Taveira Araújo <j.araujo@ee.ucl.ac.uk> Fri, 06 November 2009 11:25 UTC

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Date: Fri, 06 Nov 2009 11:25:07 +0000
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Subject: Re: [re-ECN] VIability issue #2
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Hi,

Leslie Daigle wrote:
> Viability Issue #2
>
> The expectation is that congestion exposure information will be 
> carried in IP packet headers.  Is there really enough room to do that 
> effectively (in IPv4)?

There is also the question of whether the hop-by-hop IPv6 extension 
header is good enough. It has the space, but there are limits to what 
you can do in practice (encapsulation etc). Might be worth discussing.

Joao.


>
>
> For discussion:
> This assumes tight timing -- that feedback is received and acted upon 
> such that subsequent flows will experience the same or similar network 
> state.  What are the implications (or likelihood) of different paths? 
> Or, are there other network state changes that will (could) change in 
> that timeframe (now or in future developments).
>
> Leslie.
>