[This is preliminary documentation and subject to change.]
Announcements are broadcast on one or more streams. Each stream is associated with a particular data service, and is broadcast on a separate Internet Protocol (IP) address and port. Announcement Listener can listen to more than one announcement stream at a time.
The names and addresses of the announcement streams are stored in the system registry, under the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TV Services\Announcements
The Registry Editor (RegEdit) provides access to the names and addresses of announcement streams, and enables new announcement streams to be added.
In the Announcements key, each announcement stream is represented by a value. The name of the value should reflect the name of the data service being announced. This name appears in dialog boxes and error messages. The data field consists of the IP address and port of the announcement stream, expressed in the format byte.byte.byte.byte:port, as shown in the following illustration.
In the example shown, a data service called "Webcast" is being announced on IP address 227.37.32.1, port 22701.
Typically, the installation program for a data service programmatically installs a new value into the Announcements key, reflecting the name of the service and the address and port of its announcement stream.