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).

Dependencies: None

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.