The Discovery Service provides the location of network services through Multicast DNS and DNS Service Discovery. This is a way of using standard DNS programming interfaces, servers, and packet formats to browse the network for services.
The Engine uses the mDNSResponder software library to announce the device communication service. The Discovery Service module automatically creates a usable Internet Protocol (IP) network between the device and the Yahoo! Connected TV without special configuration.
The service type has been registered with DNS Service Discovery (http://www.dns-sd.org/). The following service type is used:
Application Protocol Name:
Primary Transport Protocol Type:
The protocol does not need a fixed well-known port number. The service is registered using just link-local multicast.
First the device must search for the Yahoo! service. When the device connects, it resolves the hostname (or IP address) and the SSL-enabled port number of the service and saves it for future sessions. This avoids going through the Discovery Service every time. If the TV’s IP address changes, or if the hostname does not resolve correctly, another discovery attempt may be needed.