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Comment by wmf | Hacker News Reader

There is a debate here about whether syntactically valid 802.11 frames count as "jamming".

From the horse's mouth: https://transition.fcc.gov/eb/jammerenforcement/jamfaq.pdf

Section 333 of the Communications Act : “No person shall willfully or maliciously interfere with or cause interference to any radio communications of any station licensed or authorized by or under [the Communications] Act or operated by the United States Government.” 47 U.S.C. § 333.

If you're willfully screwing with other people's transmissions, you're breaking the law. It's that simple. The method being used doesn't really enter into it.

Wifi operates in unlicensed spectrum and transmitters and receivers are required to handle interference in this space. Is it still jamming if it's not a licensed station doing the broadcasting?

</devilsadvocate>

...I suppose it does say "authorized" there, and 2.4 and 5Ghz transmitters are authorized.

Understood you're playing devil's advocate, but the response would be: Why don't I stand outside with a WiFi antenna pointed at your house, doing the same thing, causing your WiFi devices to drop connections over and over, and then you tell me that I'm not jamming you.

Even further, denial of service attacks can be performed using totally valid and normal HTTP or HTTPS requests. In that case, it's the volume and the intent that matter.

Yes its still jamming. Even though the devices are unlicensed, you are still not allowed to intentionally cause interference with other devices. You can think of it as the requirement to use the ISM bands is you have to be nice to other users of the band.

The requirement on receiving interference means that you don't get to gripe to the FCC about other users of the band that are otherwise being nice.

For added irony, the hospitality industry claims that allowing hotspots will "cause interference with their networks".

So?!?

That's not even implicit, but an explicit part of the use of the 2.4 and 5GHz spectrums. "There may be interference. Wear a helmet."

"unlicensed" devices are still authorized by the FCC.

So your devil's advocate is unnecessary.

It always feels funny to me to refer to the ISM bands (the spectrum itself) as "unlicensed".

- Devices operating there have to be approved

- There are rules about how the devices work

- There are rules about how the _operator_ is allowed to operate the approved devices ("Operation is subject to the following conditions" sticker on most equipment).

(all of this under FCC part 15 rules)

In other bands, the operator in control of the transmitter generally needs to file paperwork with the FCC to get a license (in some systems like cellphones, the base station is in control so the subscribers don't need licenses, just approved equipment).

Just playing devils advocate but it doesn't sound like they're creating radio interference. It sounds like they're interfering at the protocol layer, which would be another matter (likely also against regulations)

You don't have to be "creating radio interference". You have to be "interfering with radio communications".

Intentionally preventing a radio communication from occurring is interfering with it.

Ultimately if you follow the network layers it gets to physical media. Without physical media nothing works. Ergo, just layering over the top of the physical layer means you still interfere with wifi comms.

How? The law as written refers to "willfully or maliciously interfere with" authorized equipment. They purchased equipment and configured it to do just that, clearly on purpose. The only possible outs here are if the equipment is a hoax and doesn't actually work, or if they managed to purchase and configure this equipment completely by accident.

Would the people who claim that those syntactically valid 802.11 frames in question aren't "jamming" hold the same opinion if it were the exhibitors, attendees, or other punters who brought in the disruptive equipment? Or are they simply being pedantic about the imprecise usage of the word "jamming"?

Bonus points: "Jamming" is not used in the law.

No there's not.

Jamming is not a relevant term.

Interference is, and it is illegal.

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