4.4.3 Packet-Pair Bandwidth Estimation Using TCP
The following sequence occurs between a client and server when conducting the packet-pair experiment over TCP:
The client sends a Describe (section 2.2.7.2) request.
The server sends a "200 OK" response that includes the SDP record.
The client sends a TcpPacketPair (section 2.2.7.12) request with a content type of application/x-rtsp-packetpair (section 2.2.6.3.2).
The server sends a "200 OK" response with three $P packets in the message body (section 2.2.7.12).
The following illustration shows the sequence described above.

Figure 14: Packet-pair experiment sequence over TCP