RTP TCP and RTP UDP Subflows
These message flows simulate an RTP stream that carries media content over a TCP connection or over UDP. The flows are intended to generate streaming media between the MN and the Network Host node and are used as subflows in the RTSP and SIP message flows. The only difference between the two subflows is the underlying protocol: TCP or UDP. The diagram shows the RTP TCP message flow. In the UDP message flow, the TCP connection would not occur.
The subflow begins when the mainflow generates a Start Subflow event and if TCP is used, the client establishes the TCP connection. In either case, the Client Port and Server Port defined in the message flow are used for the RTP stream.
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The server sends a 128-byte packet.
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The server sends a 64-byte packet.
In the RTP TCP message flow, the TCP connection is closed at the end of the message flow either when the Stop Subflow event is received or when the mainflow transaction completes.
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NOTE: These message flows are designed to be used as subflows and should not be used as mainflows. |
Modifying the Message Flow
You can specify that random port numbers, in the IANA specified dynamic range of 49152 — 65535, be used by the client by entering a 0 for the Client Port.
The packet header is represented with red in the diagram above, and the media content (Zs) is shown in black. Since RTP is not a text-based protocol, only the media content should be modified unless you are familiar with the protocol.
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IMPORTANT: If this flow is embedded in the message flow of a controlling protocol such as RTSP, the ports defined in this flow should match the client and server ports defined in the Transport header of the controlling protocol. The test will execute correctly regardless of the ports specified in the header, but if a content or Security Gateway is in the data network, it may inspect the packets and expect that the requested ports will be used for the actual data transfer. |