I have setup like below. Switch1-------------------- Switch2 | | | | | | | | | | | | PC1 PC2 PC3 PC4 I have a video traffic is flowing between PC1 and PC4. I have configured PC2 as iperf server. ( iperf -s ) and PC3 as client . (iperf -c 10.10.10.2 -P 20 -t 10000) where 10.10.10.2 is PC2 IP. now I am seeing most of the traffic in a link (switch1---switch2) is iperf. (TCP). I have observed from the logs that 1 out of 300 packet is UDP. Still I am not seeing any difference in the quality of video streaming in PC4. It looks similar compared to the case with no iperf. I am checking QOS, I have tried many options with iperf, couldnt succeed. I want to diminish the quality of video streaming in PC4. Could you please tell me what options can be used along with iperf to do it. Bandwidth between Switch1---switch2 is 1Gbits/sec. Thanks in advance