HNTF/Home Network TF Discussions/ExposingAService
From Web and TV IG
Application Exposing a Service
Submitter: Jean-Claude Dufourd, Telecom ParisTech
Tracker Issue ID: ISSUE-12
Description: An application exposes a service on the home network. In order to allow this with some technologies, it may be necessary for the HNTF user agent to advertise itself on the HN as a device. For example, an application rendered on a connected TV has access to the connected TV API for EPG information. Other devices on the HN do not have access to this information. The application implements a service exposing the EPG information and makes it discoverable by other devices.
- the application A is a TV-broadcast-related application, which is allowed to call the function returning the description of the next program.
- the application A exposes a service with one message getNextProgramDescription.
- a application B on another device discovers the service (not knowing that it is an application, it is just another service to application B).
Neither application A or B know the actual nature of the other. They may have an IP address, and they share a service type.
Justification: Allowing to share resources other than content, such as a capability (a large screen, a sensor) or an "authorization" (permission to use a restricted API).
Comments: This is a prerequisite to applications discovering each other without a "middle man": one of the two applications exposes a service that the other application may discover.