RWIN Numbers

primebasic · Post by **primebasic** » Sat Nov 24, 2018 7:54 pm

When I run the TCP/IP Analyzer the RWIN shows to be 64240 with auto tuning disabled and 655420 or something like that with auto tuning enabled.

My question is, where does the Analyzer get these numbers? Running Windows 7 Pro.

Thanks

Post by **Philip** » Sat Nov 24, 2018 11:26 pm

When you connect to the Analyzer server, it dissects the TCP/IP packet headers, and shows what your computer advertises to our server. Windows 7 and newer OSes can modify the RWIN value on the fly when auto-tuning is enabled based on your connection speed and its quality at the moment, so each packet may advertise a different RWIN number.

I hope this helps.

primebasic · Post by **primebasic** » Sun Dec 16, 2018 10:56 pm

Philip wrote:When you connect to the Analyzer server, it dissects the TCP/IP packet headers, and shows what your computer advertises to our server. Windows 7 and newer OSes can modify the RWIN value on the fly when auto-tuning is enabled based on your connection speed and its quality at the moment, so each packet may advertise a different RWIN number.

I hope this helps.

Thanks for the reply and sorry for the delay in responding.

But no, it does not answer my question where does window store the RWIN number,in windows xp it was "HKEY_LOCAL_MACHINE\SYSTEM\Currentcontrolset\services\Tcpip\Parameters" at least that is you go to set a custom RWIN.

So i'm thinking,if the Analyzer is pulling the number from my system maybe the RWIN can be set manually if i new the key it is reading.

Post by **Philip** » Mon Dec 17, 2018 8:38 am

The Analyzer has no access to your registry, it simply looks at the actual TCP/IP packets (and their headers) that you send to our server when connecting. Windows 8/10 no longer allows for setting the RWIN value manually in the Registry, unfortunately.