A unicast stream is a one-to-one connection between the server and a client, which means that each client receives a distinct stream and only those clients that request the stream receive it. You can deliver content as a unicast stream from either an on-demand or a broadcast publishing point.
Unicast streaming is the default method by which a Windows Media server delivers content. Unicast streaming is automatically enabled by the WMS Unicast Data Writer plug-in, which is enabled by default.
The following figure shows an example of delivering content as a unicast stream by using an on-demand publishing point.
As shown in the figure, there is an on-demand publishing point named TV1 on the Windows Media server called Server1. This publishing point identifies the location of the content you want to stream. The content can be hosted on the local server or a network file system. You can source from a specific file, a playlist file, or a directory. In this example, the publishing point is sourcing from a playlist file that is stored locally on Server1. When you are ready for users to begin streaming, you can create an announcement to give users the URL to the content. Because the content is being delivered as a unicast stream, each player has a unique connection to Server1.