Re: Mandatory conformance statement for CT guidelines

> but why prevent the use of the guidelines as a
> contractual basis for negotiation between two parties
> willing to follow them? 

No hindrance at all. An operator reqs doc can perfectly states "deployment fulfils all requirements stated in CT guidelines". But to claim conformance, one must publish the ICS.

> As soon as the operator say "we've
> deployed a transcoding solution that conforms to the
> guidelines", the claim becomes public and thus becomes
> invalid without an ICS.

The core issue is therefore the following:
does "deployment claiming conformance to W3C CT guidelines" imply "ICS corresponding to the deployment made public" -- whatever the context. 

I contend it does. 
a) The group envisioned two ways to verify a conformance claim: an official test suite, or failing that, an ICS publication that can be checked by the open community. Without any of these, the real meaning and value of a conformance claim appear dubious at best (verification is neither standard, nor open).
b) The guidelines have been elaborated because CT have a very substantial impact (and historically a deleterious one) on both ends of the application chain (terminals and application servers). One objective of the guidelines is to enable application developers to take measures to cater for the presence of CT, and if necessary adjust to their behaviour (especially their peculiarities regarding SHOULD and MAY attributes). Allowing formal conformance claims to remain private matter between two privileged parties, and leaving the other concerned ones uninformed seems to go against the intent of the guidelines. This would in the end turn a public standard into some kind of commercial selling point for CT vendors during tenders with operators, but exclude the impacted application and site providers from the consequences of CT.

> All other W3C standards let implementors claim conformance
> on a private basis, used for B2B. I am not saying this
> change brings anything for our use case, I just think it
> doesn't affect our use case, allows other uses of the spec,
> and addresses a concern raised during while preparing the
> transition.

I am pretty sure that legally one can claim "to implement requirements of the CT" without claiming "to be conformant to the CT" (except by inserting a lot of strong additional legalese into the document).

So I strongly advocate to keep the bar at the current level. Claim conformance, and one must publish the ICS and let people affected by the CT inspect them. If one does not want to let information about a CT out of that smoky backroom, then there is nothing we can do about it -- just that conformance claims to the W3C guidelines not bound to an ICS publication cannot be made, since it is one of the MUST requirements.

> The disclosure in the HTTP header field "Via" does not mean
> "I conform to the guidelines". It simply means "I am able to
> transcode content":
> http://www.w3.org/TR/2010/WD-ct-guidelines-20100211/#sec-via-headers

Indeed, but conformant CT disclose this information in the "via" field, so that word is bound to spread out, and confirming or contradictory feedback about conformance to the guidelines will become available. So what is the advantage to claim full conformance in secret?


E.Casais

Received on Monday, 7 June 2010 13:35:59 UTC