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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 this; sending data in the foreground while in the back ground gather statistics (throughput and jitter).

So can anyone tell me how iperf calculates these two values ?

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You can use the --fileinput option of iperf to send specific data. If you don't want to use iperf, it will get more complicated. You can use sar to measure network throughput, but not jitter. If you want to measure jitter yourself, you can look at RFC 3393.

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up vote 0 down vote accepted

I found this formula defined in RFC 3550 for the RTP (Real Time Protocol). It's the same method used to calculate the Jitter in RTC:

let's say Si is the RTP timestamp from packet i, and Ri is the time of arrival in RTP timestamp units for packet i, then for two packets i and j, D may be expressed as

D(i,j) = (Rj - Ri) - (Sj - Si) = (Rj - Sj) - (Ri - Si)

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