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Comment by ycmbntrthrwaway | Hacker News Reader

This kind of problem should be solved by transmission power control. Power is capped by standard to avoid reaching nash equilibrium. Also, Wi-Fi has various OBSS coexistence mechanisms to detect overlapping networks and cooperate with them to reduce power simultaneously for mutual advantage.

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Have any security researchers investigated the possibility of abusing these coexistence mechanisms for malicious purposes? Could be worth checking out, I think.

I would expect that the only "malicious" purpose achievable is a DoS through service degradation. Can you think of something else?

Here's an interesting attack: Suppose there are three non-overlapping channels and 70 APs, most/all of which try to pick the least congested channel. Can you persuade 67 of the 70 APs that a particular channel is very congested and best avoided, while leaving that channel uncongested and usable for the few remaining APs? Can you do so without client cooperation from the three favoured APs?

This has been used by establishments that offer paid wifi services to block portable wifi hotspots, http://qz.com/482304/the-fcc-is-cracking-down-on-companies-t...

On many networks you can just forge 802.11 disassociation frames and drop people off the wifi altogether. (In fact, enterprise wifi vendors will sell this to you as a feature - the premise being that you'll use it to keep corporate-owned laptops off unapproved access points - but there's potential for FCC trouble even there.)

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