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Comment Re:Still need to take this with skepticism (Score 1) 152

Before anyone made an infrared motion detector based on an IC, intrusion alarms were based on sonar. They would detect the doppler from any moving object, which would be a difference from the fundamental frequency. Ultrasonic ones had the advantage that they did not make audible noise. At least most of the time. There were audible ones too. These ran around 10 kHz, I think using the same speaker for the alarm siren and for the sonar emitter.

Comment Re:Interesting question (Score 2) 54

It's a pairing attack, and most locks by design pair over a short distance - so you have to take them off the door and hold them near the controller. IMO this is not a viable attack for an outsider to mount and you should not panic. If this attack worked at any time other than pairing, there would be more reason to worry.

Comment Not an effective attack for most locks (Score 1) 54

The locks in question pair over short distances - by design - and generally have to be taken off of the door and held need the controller to pair. Having an outsider cause a downgrade attack at that one critical time would be extremely unlikely. Once paired, there is no path to attack.

Sure, I would have locks reflashed if the manufacturer offered it inexpensively. But there's no reason to panic.

Comment Re: Still need to take this with skepticism (Score 1) 152

The difference would be audible at 5 kHz. Modulation of one signal with another? Remember the inverse square law. The strongest combination of the two signals is between them, not at the transducers. Where sum (too high to be audible) and difference would be the strongest signals after the fundamentals (also too high to be audible). Air and the ear are sufficiently nonlinear.

Comment Re:Still need to take this with skepticism (Score 2) 152

A sonic attack from space may sound far-fetched but they have been doing very creative things with lasers and microwaves these days.

Obviously there isn't going to be a sonic attack from someplace with no atmosphere.

Lasers actually do spread, one from space is going to end up being larger than someone's house, and easy enough to detect. Microwaves will never get that narrow a beamwidth and are easy to receive.

Comment Re:Still need to take this with skepticism (Score 1) 152

Tell that to the Dutch. Then duck!

While the economic and military weight of those large nations is obvious, the Dutch are nobody's puppets. Just spend some time there. And especially today, when they (and most Europeans) find Trump possibly more repulsive than Putin.

Comment Re:Still need to take this with skepticism (Score 1) 152

One would think that the homes of diplomatic workers are as well monitored for sound, RF, and radiation attacks as the office building.

Say you have two ultrasonic alarms working at 31 KHz and 36 kHz. The difference frequency is 5 kHz and is most likely to be heard between them rather than close to them. Nontechnical people would have no understanding of this phenomenon.

Comment Re:Still need to take this with skepticism (Score 3, Insightful) 152

So, you think because their own people were killed, they have an interest in blaming it on Russia - which has a 400 year history of peaceful relations with the Netherlands and much greater economic significance for trade - rather than little Ukraine? It doesan't make sense.

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