TomMN

Thank you for such a comprehensive response. I am testing via Win7/Firefox 20 on a SSD with 8gb of ram and an i7 cpu, so I doubt my computer is the bottleneck. After running TCP Optimizer and switching to the Washington server, my latest download result is 27.2 Mbps; about a month ago a comcast technician deemed my signal quality to be 'excellent', so as you can imagine this issue is quite perplexing to me.

Hi, I am a subscriber to Comcast cable's resedential internet service in Minnesota and I believe my tests here to be innacurate. I'm suspecting routing/distance issues, although I have tried testing with both the Dallas central server and the CDN push alternative route during 'optimal' load. Both speedtest.net and Comcast's speed tests rate my connection at a steady 62 megabits download and 11.8 up. Shaperprobe detects no shaping on my uplink and 6000-7000 kilobit shaping on my downlink, rating the average speeds to be 11125 kbps up and 55000 down. I have calculated my speeds during FTP transfers of multiple large files on both my downlink and uplink after 2-3 mins, reflecting these same results. Pingtest.net shows no packet loss and minimal ping/latency (45ms/2ms) to an Ookla-hosted server located in Dallas. However, when testing here I am averaging 38Mbps down and 7.6 up. Why is this?