3.3.3 Estimation of Packet-Pair Bandwidth

The following figure shows the packet-pair bandwidth estimation message sequence for Real-Time Streaming Protocol (RTSP) Windows Media Extension (RTSP-WME) and Microsoft Media Server (MMS) Protocol (WMSP) over a Transmission Control Protocol (TCP) connection. For the sequence over a User Datagram Protocol (UDP) connection, or the Windows Media Server (MMS) Protocol (MMSP), see the individual member protocol TDs.

Estimation of packet-pair bandwidth communication flow

Figure 18: Estimation of packet-pair bandwidth communication flow

1. Packet-pair request: After the successful connection to a server that supports packet-pair bandwidth estimation, the media player client can request a packet-pair bandwidth test from the media server. The requests are different depending on whether the transport negotiated was TCP or UDP. For examples of the exact message content and format for the Real Time Streaming Protocol (RTSP), see [MS-RTSP] sections 3.1.4.2.1 and 2.2.7.12. For examples of the exact message content and format for WMSP, see [MS-WMSP] section 3.1.4.2.1, [MS-WMSP] section 2.2.1.4.14, and [MS-WMSP] section 2.2.1.7.3. With WMSP, the Describe request is actually the same Describe request as described in section 3.3, step 1.

2-4. First, second, and third data packets: Each data packet contains packet-pair data that is sent to the client. For examples of the exact message content and format for RTSP-WME, see [MS-RTSP] section 2.2.3.2. For examples of the exact message content and format for WMSP, see [MS-WMSP] section 2.2.3.7.

5. Packet-pair response: The server sends a "200 OK" response with three $P packets in the message body. For examples of the exact message content and format for RTSP-WME, see [MS-RTSP] section 3.1.5.5. For examples of the exact message content and format for WMSP, see [MS-WMSP] section 3.1.5.5.