Confusion regarding RTSP over HTTP tunneling

Question

I had an confusion of which I searched but didn't get any answer.

I am streaming a video file using RTSP over HTTP tunneling then when I see the wire-shark to see the packets source and destination and protocol I saw a UDP protocol although i am using RTSP over HTTP tunneling.

Can any one tell me why don't I see the TCP protocol instead of UDP protocol for packets being sent from source to destination?

Answer 1

RTSP is a network control protocol. According to Wikipedia,

The default port for the RTSP protocol is 554 for both UDP (deprecated and very rarely used) and TCP transports.

Conclusion: UDP or TCP will be used, depends on which server you use and settings.

Answer 2

RTSP sets up RTP streams for streaming the video and audio. They are probably being sent over UDP instead of tunneling over the existing TCP connection.

Just because RTSP is being tunneled over HTTP doesn't guarantee that the RTP streams will be configured to use the same socket. It's up to the client to request the transport, but you can change the server to only support the interleaved transport. See this answer https://stackoverflow.com/a/3536969/759140

Answer 3

Very true but if you specify to use tcp-transport in ffmpeg it should use TCP if the server is configured for it.

If you don't specify any transport option, new versions of ffmpeg will try UDP, if that fails it will retry the connect or TCP.