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Hi I tried to execute Qos tests using Windows machine.When send some prioritized traffic usinf -S option it sends only normal data.Registry setting DisableUserTOSSetting is set to 0. When send TOS data from a linus machine to windows it works fine but vice versa is a failure.Tried Jperf2.0.2, Iperf 2.0.4 and 2.0.5 using cygwin still no use.

Please suggest on the same.

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It is not possible to set ToS byte values on sockets in Windows Server 2008 R2, Windows 7, Windows Server 2008, and Windows Vista any more.

You can use Policy-based Quality of Service in Windows 7 to assign specific DSCP values to the packets.

You can do it for specific executable like iperf.exe or by defining port numbers.

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I have made this work with jperf 2.0.2, but only under Windows XP, not Windows 7. Setting the Type Of Service to "Throughput" results in a DSCP value of 0x01 (ToS field value 0x04).

However, it does not work for UDP. IPERF fails with the error "getpeername failed: Socket is not connected" any time I try to use UDP with any Type Of Service other than None.

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