RE: [HOME_NETWORK_TF] Some use cases and requirements for broadcast TV applications



> -----Original Message-----
> From: Jean-Claude Dufourd [mailto:jean-claude.dufourd@telecom-
> paristech.fr]
> Sent: Tuesday, April 19, 2011 8:39 AM
> To: Giuseppe Pascale
> Cc: Bob Lund; public-web-and-tv@w3.org; Matt Hammond
> Subject: Re: [HOME_NETWORK_TF] Some use cases and requirements for
> broadcast TV applications
> 
> On 19/4/11 15:40 , Giuseppe Pascale wrote:
> > Furthermore, once we have discovery and pairing of 2 devices, it seems
> > to me we already have what's needed. The direct communication could be
> > just on of the possible "message exchange" mechanism and could be
> > probably be implemented with existing technologies (web sockets?)
> JCD: In
> http://www.w3.org/2011/webtv/wiki/HNTF/Home_Network_TF_Discussions/Alter

> natives
> there are proposals of structuration for messages.
> Using Web sockets means having messages as text. We can use that
> technology, or any other technology that passes text around.
> I believe the important question is: do we want to abstract the message
> structure or to stay with message = string ?
> My experience, admittedly with a UPnP implementation only, is that
> having messages automatically broken down in arguments (or parameters)
> with typed values is extremely valuable to help create the content and
> services.
> Best regards
> JC

I agree that a higher level abstraction is valuable. The challenge is - which higher level abstractions get built into the user agent? UPnP is well-defined in terms of services and abstraction of interfaces to those services. MC-DNS based services are not so well defined: the set of services is open ended and the interfaces to the services are service-specific. In this case, it does not seem practical to consider incorporating all the higher level abstractions into the UA. What I think would be ideal is a middle road where a service can advertise a higher level abstraction of its interface without having the user agent be aware of it.

Bob

> 
> --
> JC Dufourd
> Directeur d'Etudes/Professor
> Groupe Multimedia/Multimedia Group
> Traitement du Signal et Images/Signal and Image Processing Telecom
> ParisTech, 37-39 rue Dareau, 75014 Paris, France
> Tel: +33145817733 - Mob: +33677843843 - Fax: +33145817144

Received on Tuesday, 19 April 2011 15:24:30 UTC