HNTF/Home Network TF Discussions/ServiceDistribution/comments gp1

Service Distribution

Submitter: Jean-Claude Dufourd, Telecom ParisTech

Description: A document spawning other documents on other devices and communicating with them: e.g. the TV set receives and renders a document implementing some voting; the document discovers multiple phones in the home, proposes to activate voting interfaces on each of the viewers' phones, communicates with the voting interfaces, collates votes and sends them back to the channel's voting service.

Implementation: Possible implementation on top of UPnP:

• The TV receives an HbbTV application for voting, which is autostart.
• The application exposes a service to collect votes and forward them to the TV channel.
• The application discovers personal interactive devices (phones and tablets for our case) running the HNTF document UA which exposes a recognizable service.
• The application sends a suggest message with a URL to a voting interface.
• Willing users accept the suggested migration and their UA loads the voting interface.
• The voting interface document loads and discovers and binds to the vote collecting service.
• The user votes
• The voting interface document sends a vote message to the vote collecting service.
• The vote collecting service exposed by the HbbTV application receives the vote message and forwards them for a certain voting period.
• At the end of the show (or of the voting period), the application is killed by the HbbTV system, so the voting collection service disappears.
• Seeing the voting collection service disappear, the voting interfaces may shut down.

A few sketches for clarification:

Justification: This is the generic version of a crucial "second screen" usage scenario.

Dependencies: Depends on Service UI, Service provider

Comments: This UC asks the questions: how does a document discover devices running an appropriate user agent (hint: it could be a special service) ?