bandwidth - What does Jperf exactly show?

Question

I'm testing bandwidth using Jperf 2.0.2, everything works pretty good but I'm having doubt about understanding results. I'm expecting Bandwidth to be 8Mb/sec at least, but Jperf keeps telling me I got 4.25 Mbits/sec. Here is what i get in the Output window (server side):

bin/iperf.exe -s -P 0 -i 1 -p 5001 -f M
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 0.06 MByte (default)
------------------------------------------------------------
OpenSCManager failed - Accès refusé. (0x5)
[392] local 192.168.131.1 port 5001 connected with 192.168.131.10 port 62705
[ ID] Interval       Transfer     Bandwidth
[392]  0.0- 1.0 sec  0.51 MBytes  4.26 Mbits/sec
[392]  1.0- 2.0 sec  0.51 MBytes  4.25 Mbits/sec

I'm having same values on client side (between 4.25 and 4.28). Both machines are Windows 10.

My question is : Does this result stand for one way of link ? Is the BW of the link 8.5 Mbits/sec ? Or is 4.25 the maximum BW i can get, doesn't matter in which way the data is transfered ?

Thanks for your help

question from:https://stackoverflow.com/questions/65921875/what-does-jperf-exactly-show

Answer 1

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