Ok guys, here is one for you. I have a VPN tunnel between my office and another office. This tunnel is always active. Here is my problem, if I try to copy data (using robocopy) from the other office to my office, it brings their internet browsing down to a crawl. There are no issues when tying to copy from my office to the other office. I did spees tests (speedtest.net) while not copying and while copying. While not copying data, they have a download speed of between 4-6 Mbps, but when I run the test while copying data their speed drops down to about .3Mbps. That office has AT&T DSL and my office has Comcast cable.

Both offices have the Linksys RV042 VPN routers. I am attaching a screen save of the VPN tunnel settings. Both offices have the same settings.

Edited January 24, 201016 yr by todarsey

Find out what the upload speed is on the receiving network. AT&T (like other ISPs) likely have QoS set on the modems in a way where maxing out the upload speed will kill the download speed. So in this scenario, I can totally see that happening. You may want to set up QoS on that site to only allow the VPN Tunnel to use a maximum of 50% of the upload bandwidth, which will make your VPN connection slower but should help with the other users.

I gave this a try. I even set the max upload from the problem site at 50Kbps, it still bogged down thier internet. How can I verify the the problem is on our system or on AT&T's network. They are saying that the problem is within our VPN setup.

yeah.. use QOS if you can and make sure you have your numbers right.. dont get your megabytes and megabits mixed up.

Another method you could try is to use NetLimiter

http://www.netlimiter.com/

It allows you to throttle your bandwidth based on exe.. so you can say... robocopy.exe.. you only get 1mbps