[Tsvwg] Re: terminology issues in draft-floyd-tsvwg-besteffort - simple pair-wise relationships

[Bob Briscoe <[e-mail]>]

Sally,

At 18:43 24/07/2007, Sally Floyd wrote:
>>5/ Economic infrastructure: Simple pair-wise relationships (in our 
>>simplest proposal)
>>
>>Please don't imply we're making economic infrastructure more complex. All 
>>network layer relationships would still be between directly connected 
>>neighbours (pairwise).
>>
>>Currently many border contracts between privately connected ISPs or 
>>between ISPs and a peering exchange include an element of usage charging 
>>(as well as interface capacity pricing). Whether based on volume, on some 
>>notion of peak demand, or on a hybrid. We propose adding a metric 
>>(congestion volume) that is only slightly less simple than monthly byte-volume.
>>
>>However, congestion volume is much more effective, as it can be used to 
>>make networks precisely accountable for the costs they cause in other 
>>networks (unlike a volume metric, which depresses usage even when the 
>>capacity is there for it).
>>
>>So most of the inter-domain contracts that currently include an element 
>>of usage might switch to using congestion volume. And those that don't 
>>include any form of usage measurements in their contracts might stick 
>>that way. That doesn't make any contracts any more complex.
>
>Our draft says the following:
>
>    "The difficulties of deployment for end-to-end intserv or diffserv
>    mechanisms are well-known, having in part to do with the difficulties
>    of deployment for the economic infrastructure that would be needed
>    [B03].  It seems likely that cost-based pricing based on re-ECN could
>    also have a difficult deployment path, involving the deployment of
>    ECN-marking at routers, policers at both ends of a connection, and a
>    complex set of economic relationships [B07]."
>
>I would be happy to clarify it that the set of economic relationships
>required for "cost-based pricing based on re-ECN" would be pairwise,
>with a metric for congestion volume.
>
>(Note that this sentence is not about all possible forms of re-ECN,
>but about "cost-based pricing based on re-ECN".

Good - that's v precise - thanks.

re-ECN is a proposal to solely add an additional metric to IP. You are 
correct that all the possible economic structures that might be built over 
it are just what I predict might happen. And in that sense, it _can_ 
support a structure of simple pairwise relationships that could also give 
precise incentives for everyone to limit the congestion they cause.

>Our draft is not
>about re-ECN - it is simply in support of "simple best-effort
>traffic", and in support of flow-based fairness for simple best-effort
>traffic.)

Understood.

Cheers


bob

>- Sally
>http://www.icir.org/floyd/

____________________________________________________________________________
Bob Briscoe, <[e-mail]>      Networks Research Centre, BT Research
B54/77 Adastral Park,Martlesham Heath,Ipswich,IP5 3RE,UK.    [phone]