[This is preliminary documentation and subject to change.]
The Microsoft® Multicast Router (MMR) enables content servers to send data over your broadcast head end. The MMR is made up of a router program (Mrouter.exe), which routes Internet Protocol (IP) packets to a virtual interface (VIF). Each type of transmission uses a VIF. For example, to send data in the vertical blanking interval of a television signal, the MMR uses Vbi_out.dll.
System administrators can set up routes that tell the MMR which IP messages to send to which VIF by using an MMC snap-in. For more information on administrating the MMR, see Further Server Information. Applications can also create routes on the MMR by using the Msbdnapi.dll COM object. In addition to creating routes, applications can use Msbdnapi.dll to reserve bandwidth by telling the MMR when and how much data it would like to send. Msbdnapi.dll also includes an interface so that applications can reserve an IP address at a particular time. Applications can reserve an IP address in advance, send an announcement to clients that data will be sent on that IP address, and send the data at the announced time. This procedure lets client systems plan their downloading.