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I have some interested in monitoring home network because the speed of internet access is very slowly around one month ago. And it's still same at this time. I called my ISP to ask and try to deal with this problem. They said internet traffic from my network is too high, up to maximum upload speed.

If they said the truth, my guess is some machine in my network do something strange or event infected by some kind of malware and they don't know that. Of course the problem is not from my computer, I already checked. I'm not have permission to access all computers in network. So I think, the solution to find out problem is monitoring network.

In a company, they can do that easily, because they have enough money and resource. But this situation is my home network (using tp-link W8910-G) and I just a programmer. I can buy new network device to support monitoring if it not to expensive. Please help me with some guide. Thanks.

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migrated from May 8 '13 at 14:25

This question came from our site for professional and enthusiast programmers.

marked as duplicate by Sathya May 10 '13 at 4:02

This question was marked as an exact duplicate of an existing question.

If all you want to do is a quick check, get a hub (thing's cheap as water in some places), then have all devices connect to the hub, and then the hub goes into the router. This will slow down your network, and the more devices, the bigger the hit on performance. However, you'll be able to use programs like WireShark and Fiddler to snoop every packet going to and from the gateway. Have the program listen in promiscuous mode (I swear by my soul, little as it is worth, that promiscuous mode is official jargon), isolate the case, then present your clue-by-four to the offender.

Optionally, with a good router you could just check what's being accessed and by whom directly from its admin page. Or simply deny access to everything but domains in a white list, then check who's getting denied access and for what.

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