daanberg.net – Here are the instructions Add the following line to the file /etc/sysctl.conf: net.ipv4.tcp_window_scaling = 0 In this case, the problem is that your network card or extender doesn’t accept big TCP windows (when there are no problems with transmission, your computer makes those windows bigger for better performance). But with this parameter, the kernel knows that it should disable windows scaling.
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Ubuntu Quick Tip: Turn off Window Scaling if you have Networking/Internet Issues