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I've been experiencing a significant slow down of my home internet connection. ISP sent over some engineers and they didn't think there was an issue with the setup or the connection. All they did was a ping -t test and the ping ran without any timeouts.

Since my pages keep timing out, I ran the NDT test from Here's what I got:

Your system: Windows 7 version 6.1 Java version: 1.6.0_27 (x86)

TCP receive window: 114176 current, 135936 maximum 0.001331558 packets lost during test Round trip time: 285 msec (minimum), 1193 msec (maximum), 712.7 msec (average) Jitter: 908 msec 0 seconds spend waiting following a timeout TCP time-out counter: 816 140 selective acknowledgement packets received

No duplex mismatch condition was detected. The test did not detect a cable fault. No network congestion was detected. No network addess translation appliance was detected.

0.5014% of the time was not spent in a receiver limited or sender limited state. 45.839999999999996% of the time the connection is limited by the client machine's receive buffer. Optimal receive buffer: 139198464 bytes Bottleneck link: Cable/DSL modem 0 duplicate ACKs set

So, is there an issue with my machine's/router's "receive buffer"? (WTH is a that anyway?) :) Anything I can do to fix this?

share|improve this question
What is the geographical distance between you and the ndt server? None of these results indicate a problem as is, but the average round trip is 700ms or .7 seconds, which is pretty slow. It suggests you are distant from the server. – Paul Oct 25 '11 at 0:13
Approx 3300km (from – Scorpion Oct 25 '11 at 14:18
Still a pretty high ping for that distance. Could you get a copy of and test against the IP address given in NDT, it will tell us where in the path the delay is. – Paul Oct 25 '11 at 21:27
I will give this a try. One of my biggest concerns is that, I'm seeing serious problems when connecting to HTTPs sites. Worst affected are services like GMail, GDocs. I was wondering whether there was something fishy going on at the ISP. But, I've found no evidence of traffic shaping or anything else. – Scorpion Oct 26 '11 at 5:02
Here's WinMtr Data: – Scorpion Oct 26 '11 at 5:35

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