Decreasing speeds

[GoFigureItOut]

I really don't know how to describe my friends situation technically, but lately her Internet has slowed down to a crawl. She thought her computer was infect, so she brought it to me and I reformatted and updated her PC to Windows 7 from XP. The problem still exist. Did a speed test and she's getting what she paid for. The problem only happens at night. So, I got the feeling someone is leeching off of her Internet. Almost every month she has nearly reached her data cap, which is very unusual. If someone did use Backtrack to access her Internet, can it be traced at home? I was looking at Wireshark.

[TRWOV]

Put a new WPA key on her router and turn SSID off (write down the network name as the router won't broadcast it).

[fullinfusion]

^ what he said.

[Widjaja]

Besides the above.

Changing the name of the SSID to something which sounds like a virus or something related hacking will deter the parasites.

[GoFigureItOut]

Originally Posted by TRWOV

Put a new WPA key on her router and turn SSID off (write down the network name as the router won't broadcast it).

Yea, I changed her WPA key several times and the amount of data usage is higher than what she use her Internet for. I never tried disabling the SSID. I'll give it a try. However, I read a few articles that mentioned hiding an SSID does not really matter anymore. A very determined person could use Kismet to search for even hidden ones. What I was wondering, is it possible to use WireShark to see what someone is doing if they do leech onto her Internet?

[RCoon]

Originally Posted by GoFigureItOut

Yea, I changed her WPA key several times and the amount of data usage is higher than what she use her Internet for. I never tried disabling the SSID. I'll give it a try. However, I read a few articles that mentioned hiding an SSID does not really matter anymore. A very determined person could use Kismet to search for even hidden ones. What I was wondering, is it possible to use WireShark to see what someone is doing if they do leech onto her Internet?

Or just log on to the router and deny all access to the router except from her specified mac addresses.

[TRWOV]

I'm not familiar with Wireshark but you could log into her router and see what devices are connected when she gets the slower speeds. You could restrict access to just her computer as RCoon said.

Is she on cable or ADSL? Cable gets slower when many clients connect, not just to her network but to the specific node of her neighborhood as each node acts as a hub (shared bandwidth).

[brandonwh64]

As coon said, MAC address filtering is quite good unless for some odd reason the thief finds her MAC address and clones it on his machine.

[Xenturion]

While it is possible that she has a neighbor using her network to download 'hella' torrents when he gets home for the day, I've got another suggestion you might consider. It's actually a fairly commonly overlooked issue: Wirless Network Channels. Depending on how many concurrent wireless networks are broadcasting in her area, there is massive potential for interference if the Wireless Channels the routers are set to use aren't optimized. I ran into a similar problem myself at an apartment I was staying in a year or so ago. We ended up calling the ISP because, during peak times, our connection would become essentially unusable. It pretty much hit me as the tech was going over possible causes. I changed our router's channel and it was smooth sailing from there on out.

Steps:
Download INSSIDer. It's a freeware wireless network scanning utility that will tell you the signal strength, channel, router type, signal type, etc. for all the wireless networks in range.
Find her router amongst the list of signals and identify which channel she's using.
Look at the other routers, see if any are using the same channel.
If any other routers are using the same channel, change her router to use an unused channel, I usually avoid the extremes of the channel numbers (say 1-3 and 15+) because not all devices can see a network broadcasting on those channels. I usually try to pick a channel that's at least one channel away from another network. (IE if there's network A on channel 5 and network B on channel 9, I'd pick channel 7 for the router)

[brandonwh64]

The best wireless channel around me is 11 but this maybe different from were she lives.