Will a WIFI emitter affect HE like it does Simplisafe?


#1

Just read this article and was wondering if our system can be similarly affected?


#2

I don't see why not. If you jam the frequencies used for wireless sensor communication, things aren't going to trip. I have some experience with testing this on other types of wireless security sensors, and it's totally possible. There's no reason the same concepts wouldn't apply to the 2.4ghz range for Zigbee or Wifi sensors, and the 900mhz range for Z-wave devices. My testing was on different frequency ranges, which included sensor to panel communication, as well as wireless communication to the monitoring station. (I work in security... paid to be paranoid)

This is one of the reasons that I don't feel that a home automation system is a good security system platform. If you want a security system, get an actual security panel (I prefer Elk Products) and wire your sensors in as much as possible. EOL resistors make it much harder for people to bypass sensors also, and the values of these differ between vendors. For this reason, it's NOT a good idea to put a sign out clearly advertising what brand of panel you have, although most alarm installers put the EOL resistors on the panel side, which does nothing. Alarm your upper windows (almost no one does this, so it's a common entry point), put in motion sensors, put in pressure sensors under the floor (or even under your roof sheathing).

However, the reality of it is, how many burglars are going to have the knowledge or the motivation to try to subvert your security controls with a jammer... or even try to subvert your system at all? Most burglars are opportunistic, and the knowledge that your home has a security system will typically make them move on to a house that doesn't have one. That said, if you have something specific they want and they know you have it, then that could be motivation enough. But we're probably talking heist-level stuff here... gold/silver, jewelry, a famous painting, expensive violins, a large gun collection, etc. Most people don't have that stuff, and if they do, the insurance costs on it will dwarf the cost of a solid security panel. I know a guy who has some amazing things, and his insurance is over $10k a month. He's definitely not trying to save money on security with an HA platform and some cheap zigbee sensors. The security system he has is awesome, but it's still mainly a deterrent for opportunistic burglars, the real security is not telling the world that you have a bunch of great stuff worth putting in a lot of effort to steal. I was in high school in the early 1990's. Car stereo's were a big thing then. The guys that put a Rockford Fosgate or Phoenix Gold sticker on their back windows got their stuff stolen repeatedly.

Also, get a scary looking dog. When someone gets within 100 feet of my house, mine is at the door barking and growling like he's gonna go right through the glass and rip their arms off. I keep my outdoor lights on all night, my neighbors don't. I have clearly visible (and working) surveillance cameras, my neighbors don't. Basically, just make sure your neighbor's homes are more attractive to a burglar than your own. :slight_smile:

Another thing, hide your safe(s), and bolt them to the floor. I know several people who were burglarized and the thieves just picked up the whole safe and took it elsewhere to get into it. My old neighbor lost 6-figures worth of cash and gold this way, they never caught the guys, and insurance won't cover that sort of thing. I can bypass an electronic lock on most mass market gun safes in under 5 minutes using a $20 tool that I can purchase on Amazon, so even if you bolt them down, you should still keep them hidden.

I know you were looking for a short answer. The answer is yes. :slight_smile:


#3

If a device isn't shielded correctly, you can easily overload the device. Many years ago there was a pickup truck (in the early fuel injection and analog cell phone days) that if you used a cell phone near it, the ECU would somehow receive that frequency and shut off. It basically rebooted the computer. I am speculating a bit about why, but I would guess the microprocessor had a floating input, or some part of the circuit was a certain length and prone to receiving this particular frequency. So yes this can happen.

I wouldn't count on any device like Hubitat or these alarm systems to have extensive RF testing done to them. Things like cars, airplanes, and medical equipment for sure gets tested, but consumer devices probably not. From what I understand these type devices are tested more for not emitting bad RF. In fact doesn't the FCC 15 state these have to accept interference from other sources?


#4

I appreciate absolutely everything you wrote here. One of the benefits of my transition from Lowes to HE was that I was able to get a lot of extra sensors really cheap, so I did add them to all of the windows on the second floor too. I also misadvertise my security system so if a burglar bothers trying to bypass it they might try something that may not work with HE, and I have cameras that function independently from HE for redundancy. I guess what I was interested in finding out was that if the same $2 WIFI emitter mentioned in the article could also affect HE given the way it operates, or if there was something that would make it immune or less prone to this specific 2 dollar tool. From your post it sounds like it makes no difference and HE would likely be equally affected. Thanks.


#5

Yes, you are right, commonly they are trying to make sure the device itself does not interfere with communications and not the other way around. I guess my only solace is that if someone were to try to get close enough to any contact sensor or other device to use the WIFI emitter they would be picked up by my cameras first so I would still get notified of a potential intrusion.


#6

Probably the only way to find out is to try it. For $2 it might be worth finding out. I personally don't use the Hubitat as a security system, and for less than $100 I wouldn't expect it to be a first line of defense. Nothing against the Hubitat, but there are dedicated hard-wired security devices for a reason.


#7

Just for clarity, that $2 wireless emitter was using the 433 MHz frequency so that same device would not have much of an effect on zigbee or z-wave devices. But, as @signal15 mentioned, that same method, targeting zigbee or z-wave is possible.


#8

You know. I want to call BS on this, but with a caveat.

Yes, as others have said, the indicated tool could certainly block the signal from an individual sensor, or if the attacker had sufficient power, maybe even the Hub.

However, and this is a big However, Jamming is non-trivial except in the most basic sense, and in order to put sufficient power out to Jam your WiFi (for example) would likely require a fairly obvious directive antenna and a fair bit of amplifier power.

WiFi is also spread spectrum utilizing both Direct Sequence Spread Spectrum and OFDM, with fairly sophisticated collision avoidance mechanisms, which would make it relatively difficult to Jam.

Zwave and Zigbee are more vulnerable just because of power and simplicity if for no other reason, but the attacker would have to KNOW that you were using Zwave or Zigbee and be sophisticated enough to Jam both or just the one you're using.

Now, Simpli-Safe was also using 433 Mhz in the original Simplisafe system that was modulated in unencrypted ASK, and a reasonbly sophisticated bad guy could intercept unencrypted keypad entries and thus have the key to your house... SimpliSafe Security Advisory – Simple or Secure Security Blog

So. In my opinion (note the opinion word there), there is a bit of truth in this article mixed with a lot of FUD.

If you're being targeted by a sophisticated enough bad guy to accomplish this sort of Jamming/Hacking, I'd suggest the "bad guy" is probably the Police, FBI or similar agency, and your problems are greater than the typical smash and grab burglar or script kiddie.

Personally, I'd worry more about securing my UPNP enabled router than whether some guy in a white van with antennas on it was jamming my security system so a bunch of black hooded thugs could steal my Sonos speakers.

But opinions vary!

S.

P.s. In terms of security advice/wisdom, I tend to agree with @signal15 here. Big dog, obvious cameras, outdoor lighting, mixed with common sense, and perhaps a weapon you're trained and comfortable with...if you're not of the dog owning persuasion.


#9

This is the kind of in depth discussion I was hoping my post would elicit. Very insightful and interesting.