Re: [apps-discuss] Fwd: New Version Notification for draft-shelby-exi-registration-01.txt

[Zach Shelby <[e-mail]>]

On Apr 11, 2012, at 11:59 AM, Carine Bournez wrote:

> On Wed, Apr 11, 2012 at 05:30:05PM +0900, Yusuke DOI wrote:
>>> you have to define schemaID for your application, (2) harmful, since it tries
>>> to redefine the mechanism for options that is already defined in EXI 1.0,
>>> at least for the schema-informed mode.
>> 
>> I cannot understand (some of) your point. I think EXI spec does not define any 'mechanism for options' according to schemaId definition. The EXI spec (in schema-informed mode) is useful only if decoders know the running application a priori.
> 
> 
> Rephrasing: the EXI 1.0 spec has a mechanism to tell the other end that
> schema-informed mode is in use, and the EXI 1.0 spec says that the 
> application level has to take care of defining the form of schemaID.

Right. This is what we are trying to fix at the application level, by providing a registry where this information is easily available to anyone on the Internet that runs into that media type. Just waving our hands and hoping that in some specification, somewhere, the interpretation of schemaID has been defined does not work on the Internet. The knowledge alone of application/foo with content-encoding: exi does not tell you sufficient information for Schema-informed mode to actually decode the payload. For encodings like gzip or deflate, that is obviously not a problem. 

Now, if EXI folks think that the way we are approaching this is not the right one, how do you propose to fix the problem? 

One possible way would be for application/foo media types that expect to be used with exi content-encoding (Schema-informed mode) to include the needed schema information in the application/foo media type registration. Not sure how easy it would be to add such information there, or if some instructions would be needed regarding that.  

Zach

-- 
Zach Shelby, Chief Nerd, Sensinode Ltd.
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