About multicast information files

The Multicast Announcement Wizard creates both an announcement file and a multicast information file. The multicast information file is a Windows Media metafile with an .nsc extension. The multicast information file contains information a player needs to use in order to decode a stream. Before receiving content delivered as a multicast stream, the player must access the multicast information file to extract the following information:

• Multicast IP address
• Multicast port
• Time-to-live value
• Default error correction span
• Multicast logging URL
• Unicast rollover URL
• Stream formats used by the content being delivered

If you make any changes to the publishing point configuration, such as modifying settings for the multicast data writer plug-in or renaming the publishing point, you must use the Multicast Announcement Wizard to create a new multicast information file so that players will be able to connect to your content.

Notes

• Multicast information files must include all the stream formats used by your content. If the stream formats are not listed in the multicast information file, clients cannot access the multicast stream.
• Multicast streaming and the WMS Multicast Data Writer plug-in are available only if Windows Media Services 9 Series is running on the following editions of the operating system: Windows Server 2003, Enterprise Edition and Windows Server 2003, Datacenter Edition. If you are running Windows Server 2003, Standard Edition, these features are not supported.

Related topics

• About stream formats
• Announcing content
• How multicast works
• Logging data about multicast streams
• Working with the announcement wizards