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Disabling Wireless Networks?
An Ominous Coward asks: "The University of Florida student chapter of ACM hosts a yearly programming competition for students throughout the state of Florida. It is based on the ACM International Collegiate Programming Contest, and for the past ten years has been very successful, currently drawing a crowd in the hundreds. However, this year was the first we had a problem with wireless networks. We doubt that cheating was the intention, as no one had SSID broadcasting turned off (as far as we know). Wireless networking gear is quite inexpensive now. And while we don't believe it affected the contest this year, we would like to take precautions for future contests. Is there any way to disable all wireless networking in an area about the size of a large lecture hall?"
Make everyone work in a shielded metal, enclosed cubicle and change the name of the contest to:
"Code in a Can"
--Chris
just run a microwave oven in the back, a few cordless phones, a few rouge APs
hopefully that is enough noise to kill most networks...
or just make it very clear: NO WIRELESS NETWORKS. Walk around with netstumbler and a directional antenna. After a few people get antennas pointed at them, the networks will stop.
-Grump
Is it true that more people vote for the winner of American Idol, than vote for the president? -Ali G.
... use a high-signal white noise generator.
http://tinyurl.com/4ny52
Simple. You simply forge the MAC of the access point (or just use the broadcast MAC), and spew dissociate/deauthenticate frames. As long as you're transmitting, nobody in range of the transmission can associate with an access point.
This was the basis for the AirJack tool.
.@.
There was a project that would broadcast tons of fake SSIDs in an attempt to obscure the right one.
... I don't care if they want to check, but they can get up and do the checking in another room ... 1 distraction leads to 2 and on and on).
Given that principle, would it be possible to create a box that intercepts and responds with junk to any 802.11 packet it encounters?
Not sure, but I've given it thought myself when giving a class where everyone is sitting there checking email (when you give a 3-day bootcamp on a subject everyone starts to drift -if- there is a distraction
You don't necessarily need to -block- 802.11 traffic if you can make the existing networks worthless by giving junk back to the 802.11 clients. Perhaps masquerading the MAC of any AP you find active would be enough?
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.
Or, take a look at everyone's laptop as it comes in. They can leave the card with you (like a coat check), or, if it has integrated wireless of some sort, let them use a spare desktop or laptop you've brought for the purpose.
That would be a lot of overhead. Are you going to check the specs of every system to ensure that it doesn't have a centrino processor(If someone were to cheat they would have no qualms about switching/removing stickers). I don't know how many powerbook/iBooks they get, but are you preparted to lift up the keyboard to look for an airport card on each one? Plus they could always sneak in wireless cards.
It's much more practical to find a way to disable the networks instead of the cards.
What we really need to do is figure out how to disable wireless phones in an area about the size of a movie theatre or concert hall. Perhaps something slightly less lethal than a shotgun.
agreed. A setup where the host controls the show is best for this situation. I personally participated in the ACM's programming contests during their Fall '01 and '02 competitions, and can give info on the environment they use. (FWIW, we never got past the regional competition either year).
Basically, the contest was staged in a typical university computer lab, and all the machines were using some special image created just for the contest and installed that morning. A log was created of all activity from the rooms being used, and checked later (I think the admin did this via a router or firewall). Any activity other than the network connection required for the submission software got your team DQ'd.
The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
There are several 802.11 denial of service attacks explained in this paper
It's simple. Someone at OSConf in Toronto this year had no trouble taking out the entire WLAN with a laptop broadcasting in Ad-hoc mode on the same channel, same SSID.
Idiot. *mutter*
Random and weird software I've written.
Most of the other posters here have mentioned ways to flood the network with bssids, etc. Chances are this will not work since the bssid's will be chosen by the cheaters. You will probably have more luck running kismet or some other sniffing tool to monitor the wireless network. Then you can see if anyone tries to use the wireless network.
Is it still violating FCC regulations if its in an unlicenced frequency?
It IS licensed spectrum! Or, more accurately, about half of it is. Amateur Radio is assigned a portion of that spectrum as a "licensed operator" and you cannot harmfully interfere with them.
In addition, you can't exceed the limitations given in FCC Part 15.
All opinions presented here aren't mine.
Can you even imagine the smell of a lecture hall full of hackers recently goreged on frozen burritos? Yuck.
I don't want free as in beer. I just want free beer.
Microwave ovens generally operate at 2.450 GHz, which only intersects 802.11 channels 7 through 10.
And the humans won't explode if you poke a few holes in them with a fork.
A good solid EMP should disable all wireless networks in the vicinity*
*as well as all computers, electronic gadgets, and vehicles built before 1980's
The trouble is generating one. You can use either:
- Very large capacitors, or...
- A nuclear device **
**With a nuclear device, you will not only disable all wireless networks, electronics, and vehicles built before the 1980's, but all humans, buildings, and organic matter for a very wide radius. No FCC complaints, but alot of DoD complaints will result.
Frink: Nice try floyd, but you were designed for scrubbing, and scrubbing is what you shall do.