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I have a network with a really high ping (usually more than 500ms) except for one laptop. And in that laptop the ping is usually 5ms.

I've tried: - using same model laptop - compare lan driver version - test on another cable/docking station - compare gateway, submask, etc. - enter with other user in the pc (the users are in a win server 2003 active directory) - run with all the other devices disconnected from the network. - disconnected the WIFI from the "fast" laptop so there is no chance to catch wifi networks. - compared with spiceworks and found no big differences. (Almost the same apps and fixes)

I do not have access to the router config and firewall. But that has been tested and nothing was found. And there is the laptop working through the same network/firewall.

What am I missing here? Help is really really appreciated.

Thank you in advance.

Im using speedtest.net to test. Basically the internet is slow and the problem seems to be the ping. There is switching involved. Although I do have limited access to almost all devices.

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Pinging to where? –  joeqwerty May 27 '11 at 15:07
    
In addition to joeqwerty's comment: Is there switching involved? What did the administrator running the router/firewall say? Does the problem follow the laptop or the port it's connected to? What happens if you give the "good" laptop's IP to another one? –  Hyppy May 27 '11 at 15:11
    
Try pinging to the device at the furthest edge of your network (firewall or router) to see if you have the same results. If so, then it's an internal problem. If not, it's external and it's not likely you can do anything other than report it to your ISP. –  joeqwerty May 27 '11 at 15:29
    
@Hyppy Using now the ip of good laptop, same thing, 500ms ping. The admin said everything was OK. –  Artur Carvalho May 27 '11 at 15:32
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Run a tracert from the good machine and a bad machine to www.speedtest.net and see if the path is the same. In addition, this is a longshot, but run a packet capture on the good machine and a bad one and run your speed test. Look for any ICMP redirects in the capture on the bad machine. If you see any on the bad machine but not the good machine then that's an indication that the traffic on the bad machine is being re-routed through a different path. –  joeqwerty May 27 '11 at 16:06

1 Answer 1

You might also want to use port mirroring on the switch to see if there is a crap ton of broadcasts happening.

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