Re: [VIPR] Agenda for 2011/09/23

[Dean Willis <[e-mail]>]

On 10/7/11 8:51 AM, Marc P
> Yes, but the difficulty here is how to choose this route.  The proposal sent by
> Hakim, i.e. sending the capabilities of the endpoint together with the SIP route
> and ticket, would permit this, as only the VIPR domain the closest to the end
> user would be able to send the real capabilities of the endpoint (extracted for
> example from the SIP registrar).  The transcoding is interesting, as an
> intermediary using it could eventually claim to better route than the direct
> route.  Perhaps what we need is a new media feature tag that would indicate that
> a capability set is "native" (i.e. built directly from the SIP registrar or
> information coming from the endpoint), instead of been from a intermediate media
> point, like transcoding.


If we create a situation where there is an incentive for an intermediary 
to mis-state a capability set in order to "capture" more 
revenue-generating traffic, then the intermediaries are going to lie 
like politicians seeking re-election.

I think this is a MUCH harder problem than we currently realize.

Even Hakim's proposal requires that route-validation also validate the 
offered capabilities, not just evaluate them and choose the richest set. 
This is hard; a motivated intermediary could probably convince a 
test-bot that it is the target instead of an intermediary.

--
Dean