How does iperf calculate throughput and jitter?

Question

I've read that Iperf basically tries to send as much information down a connection as quickly as possible reporting on the throughput achieved. This tool is especially useful in determining the volume of data that links between two machines can supply.

Is it possible to gather the same results by sending regular data, as in not testing data?

What I'm trying to do is sending data in the foreground while gathering statistics in the background (throughput and jitter).

How iperf calculates these two values?

Answer 1

This is the closest thing I've found

http://openmaniak.com/iperf.php