The MPLS WG Archive

[Grenville Armitage <gja@dnrc.bell-labs.com>]

Francois,

I'll pull out each major discussion point separately. In this
email my response re ECN.

	[..]
> >#1 Remove section 11.
	[..]
> It has been useful and necessary for the WG to understand how ECN could
> share the EXP space with ECN (should ECN be required in the future),
> in order to progress with Diff-Serv over MPLS support.

Regardless of the ongoing debates in other mailing lists over the
utility of ECN, it isn't necessary for *this* document to specify
anything regarding ECN support. It is sufficient that diff-ext-05
state ECN isn't precluded, there is no need for diff-ext-05 to
speculate on how ECN might be supported. Leave that for another
document.

I suggest it is sufficient to state the following in the intro,
abstract, and/or conclusion:

 "The architecture described in this document does not preclude the
  signalled or configured use of the EXP bits to support protocols
  such as ECN [ECN][MPLS_ECN]. However, techniques for supporting
  ECN in an MPLS environment are outside the scope of this document."

Done.

cheers,
gja


> It seems
> appropriate to me to also reflect some of this in the Diff-Serv draft.
> If we had come up with a Diff-Serv solution that was incompatible with
> ECN, I think it woudl be useful for that document to say so. It turns
> out we feel that ECN and Diff-Serv could coexist and that the impact on
> the Diff-Serv over MPLS solution are reasonable. We might have tried to
> be too specific in the current text (considering the early stage of ECN
> over MPLS) but I think some description of why the current Diff-Serv
> solution does not preclude ECN and how those could share EXP space is
> useful information.
	[...]
________________________________________________________________________
Grenville Armitage                    http://members.home.net/garmitage/
Bell Labs Research Silicon Valley