Re: [TERNLI] question about layer focus

Lars Eggert <> Tue, 13 June 2006 21:34 UTC

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From: Lars Eggert <>
Subject: Re: [TERNLI] question about layer focus
Date: Wed, 14 Jun 2006 00:34:37 +0300
To: Joe Touch <touch@ISI.EDU>
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On Jun 13, 2006, at 19:03, Joe Touch wrote:
> However, some of the background reading suggests link-transport
> interaction. IMO, this has been the previous issue with some previous
> attempts near this solution space; is this difference being  
> addressed in
> this BOF, or is the BOF setting a boundary (i.e., only transport- 
> net and
> net-link are allowed, but not transport-link?)

The reading list contains both high-level background material as well  
as documents on specific proposals that various groups have brought  
forth. I'll try to structure the reading list by topic in the next  
update of the BOF proposal.

>  Any property that is of a link, rather than of
> a path, is inappropriate to expose to the transport layer. There are
> current exceptions that are based on 'best guess', i.e., starting PMTU
> at the MTU of the first link hop as a starting point; that's fine, as
> would any other similar starting guess. However, I think of that as a
> guess that could as easily have been passed through the layers (i.e.,
> the network layer indicates that all paths originating from this IP
> address start with the MTU of its link, passing that then from the net
> to the transport).

I agree with you on this. There will likely be a presentation on the  
approach to the problem space that this document is related to during  
the BOF, hence I listed this as part of the reading list.

Lars Eggert                                     NEC Network Laboratories