We just got a VPLS circuit installed between two office locations and I’m running some initial tests on the connection. We are committed to 10mbps at each of the endpoints, however when running ipref tests looks as though we are getting 500-700kbs. I spoke to the provider who seems to be blaming it on our Windows OS Operating System TCP Window size. After changing the windows size in the ipref test this increases the bandwidth speed up to about 5-7mbps.
So because of these tests the slow speed looks like its isolated to the TCP window size. The question is why is the bandwidth transfer from our other providers absolutely fine, however with this one they are telling me to change my TCP window size across the whole network ???