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vueko | 1 year ago

Yes, it's pretty trivially easy to detect, even without fancy EW equipment. At one point I admin'd a college dorm's network, wifi/wired, and we didn't allow personal APs for interference reasons (you could run your own switch or router as long as it wasn't a WAP). Our run-of-the-mill networking hardware could find signals and triangulate them down to a couple of feet. A couple residents were flummoxed to learn that the "hidden network" thing doesn't actually do anything, which was hopefully at least a useful educational moment.

Any decent SDR can notice such things, presumably not to mention actual EW equipment. It's only really with sub-noise-floor gold code type stuff where a signal doesn't jump out on a waterfall spectrum chart, and even then it's generally fairly obvious at close range. I can only speculate as to why that didn't actually happen here.

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rendall|1 year ago

> we didn't allow personal APs for interference reasons

For "interference reasons"? Would you mind expanding on that?

__d|1 year ago

I imagine the issue was that in earlier WiFi versions, there weren't a lot of channels available. You basically got 2 or 3 (depending on which country you were in) non-interfering channels. The protocols also dealt with congestion less well, I think.

On a university campus, let's assume that at least one of those channels is taken by the campus WiFi, possibly more if they have separate networks for staff or whatever. At that point, you start getting a few dozen private networks running in the dorms, and the campus network(s) grind to a halt.