Hacker News Reader

Comment by avree | Hacker News Reader

Even pre-WiFi 7, there are companies such as Cognitive who allow you to detect motion (as well as occupant activity, etc.). I implemented such a system at my previous company which sold Wi-Fi.

View on HN

Yes, some vendors have shipped their own implementations. There's also custom firmware for some radios. But standardization will bring scale and ubiquity to non-technical users. Are millions of city occupants ready for transparent walls, floors and ceilings? Are businesses ready for remote keystroke detection?

I guess the future is RF blocking walls. Might even be a good thing since It'll allow for less congested airwaves for yourself.

Maybe something like this foil-backed gypsum board, https://www.goldbondbuilding.com/products/drywall-panels/foi...

RF/sound blocking drywall for SCIFs costs a small fortune, https://www.quietrock.com/products/quietrock-530rf

EMF shielding case study, https://www.zokazola.com/emf_reduction.html

You can get a lot of sound proofing by double layering drywall with an air gap in-between in exchange for some floor space.

My apartment ceiling has a ~60cm air gap with air conditioner ducting and stuff inside, not sure how responsible it is but I hear basically nothing from above me. Same for the side walls although I believe those are just super dense fire proof walls.

I suggest the opposite - it will enable many exciting smart home possibilities which in some could seriously reduce HVAC energy needs beyond what’s possible today.

You could leave the internal walls RF transparent. Which allows you to do whatever you want without your neighbors wifi scanning you.

Building energy efficient homes also does that. No need to over complicate the situation.

Lot easier to deploy WiFi in existing homes than build new one. It’s about easy impact on the world.

> remote keystroke detection

Wait what..? Is it that good? That's even more terrifying

2015 paper, https://dl.acm.org/doi/abs/10.1145/2789168.2790109

> We implemented the WiKey system using a TP-Link TL-WR1043ND WiFi router and a Lenovo X200 laptop. WiKey achieves more than 97.5% detection rate for detecting the keystroke and 96.4% recognition accuracy for classifying single keys. In real-world experiments, WiKey can recognize keystrokes in a continuously typed sentence with an accuracy of 93.5%.

More papers on keystroke recognition: https://scholar.google.com/scholar?hl=en&as_sdt=5%2C31&sciod...

60Ghz mmWave radar (coming to Wi-Fi via 802.11ay) has higher resolution, shorter range and low ability to penetrate building walls, but can pass through unshielded windows: https://news.ycombinator.com/item?id=30172647.

Thankfully I use an extreme custom keyboard layout so I wish them luck.

That's about as hard as decrypting substitution cipher. Just think about the problem for a second, you will figure out how to trivially go around it.

Well I think with enough time you could just use the key press model to try different configurations until you got one that gave intelligible results. The process could be easily automated if the resolution is enough to support accuracy in the 90th percentile

That’s just as secure as ROT13

Do you also have your number keys remapped non-linearly?

> there are companies such as Cognitive

It's my understanding that there have been companies trying to sell solutions like this for people-tracking indoors for supermarkets/grocery stores, shopping malls, large department stores for at least 7-8 years now.

(edit: Stuff like RF beacons built into shopping cart handles, right? Since the shopping carts are centrally owned/managed/controlled and with unique serial numbers, and mostly don't get stolen or leave the property.)

Your understanding is correct, but most of those were based on iBeacons/NFC/other tech and not Wi-Fi.

There were some things around WiFi, but on a higher level, e.g. recognizing unique radio mac addresses that were sending probes for their home SSIDs. Big reason most devices will now randomize their MAC address until actually authenticated with a network.

Reply on news.ycombinator.com