This optimization needs to be run on each computer that will access OOL. Once downloaded (there’s no install), run DrTCP and start by changing the following settings:
Set the TCP Receive Window to one of the following based on your speed tier:
64240 for 10mb or less; 128480 for 10-20mb; 256960 for over 20mb
Set the Path MTU Discovery to Yes
Select your network card in the drop-down list and then set the MTU to 1500
Click the Apply button and then the Exit button.
You must reboot for these changes to take effect!!
After rebooting, re-run DrTCP on the machine, re-select your appropriate network card from the drop-down list and verify that all the settings were retained.
Original link
Download DrTCP here
Screenshot of settings