I am rather new to network programming and wanted to know if anyone more experienced can help me. What I want to do is to measure the qos characteristics of a connection between two computers. I would like to see how these characteristics change over time i.e. see effective bandwidth, delay and jitter. I know about the differences of TCP and UDP but do not see right away which I should use and how. That is if I use TCP then the bandwidth will grow until congestion and then be reduced etc., but can i measure delay and jitter? Also if I use UDP, will I then decide the bandwidth to pump out and then measure delay and jitter from that bandwidth?
Should I do these measurements by first establishing a tunnel where do i get the parameters of a connection from? Are there maybe some good tools that I could use? I have been reading about RTP and RTCP thant maybe would be useful also?

All help will be very much appreciated.

Halldor