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Comment I went reading some of the specs... (Score 1) 292

I actually took a few minutes and skimmed some of the online training modules that USDOT put out for developers. There are problems, and they "sort of" admit to them. If I read this correctly, there are only ~105K possible keys, though I'd love to be wrong - otherwise this should fall to a brute-force attack in seconds. Just slam on your brakes, record the outgoing packets, and try every key until one decodes as "putting on my brakes, dude!" And now you have enough information to force any car to let you merge in, whether the driver wants to or not. Which, heck, might actually improve safety. I don't know. Could go either way.

As far as privacy, it's still pretty weak (=totally cracked). They aren't recording the MAC addresses of the cars per se, or so they say, but you could from first principles tell what factory a car came from and its approximate date of manufacture. That's useful - narrows it down to a manageable number of vehicles. Or just passively monitor an intersection with a license plate reader and record every "putting on my brakes, dude!" message. Now you have a table of license plates and MAC addresses. I can't see, frankly, that licence plate reader vendors won't sell this as an optional feature for a modest additional charge.

A big problem, and one discussed elsewhere, is that re-keying this thing is going to be a pain. It doesn't support over-the-air keying, and the intent is that a dealer will periodically re-flash new certificates/keys. That's a tall order. For this to work, cars will have to accept some pretty old keys (insert stars wars joke about older codes but they check out, above), increasing the odds they'll have to accept previously compromised keys. Which will probably be had by dumping the flash.

Anyway, the layer 1 and 2 protocols over the air are 802.11p, and what looks like a quasi-layer-3 is IEEE 1609. So get started.

Another commenter has asked about GPS errors. Looks like the standards explicitly support a very-short-range form of differential GPS and I wouldn't be surprised to see some sort of localizer used to reinitialize a Kalmann filter at some point. Pretty easy these days.

Comment Commercial, production laundry operations (Score 1) 139

Same thoughts here - just take a moment and enjoy it at home, but... I used to work for a company that made apparel. There is a plant in the deep south with washing machines the size of dumpsters - they wash 288 jeans at a time. Over 10,000 pieces are washed, dried, pressed, and folded a day. People stand there and manually turn them wrong-side-out and then, after laundry, turn them back again. They have to check the pockets to make sure there isn't any pumice left in them from "Stone Washing" - the rocks will mess up an iron. Extremely low-tech, labor intensive. Most of it is done in Mexico, except during droughts when it's hard to get enough water there (I'm not making this up), so they keep the operation in Alabama running all the time and they just add a couple of shifts during dry weather. A jeans-folding robot would need to come in pretty cheap so its Net Present Value would be less than minimum wage. Wild guess, maybe around $10K would be the breakeven point.

Come to think of it, with Alabama in record drought right now, I wonder if that laundry is running? :-)

Comment Re:GPS clock (Score 1) 291

The cool thing about CDMA is that it won't work without precision time standards in each of the base stations - i.e., GPS receivers with antennas fed through known lengths of feedline (or, alternatively, GPS receivers with known lengths of wire providing a 1 pulse per second reference). Net result is that CDMA can give sub-ppb time reference, and it works great indoors, too. Probably overkill for getting the kids up in the morning. :-)

Comment Re:How about the FCC just does its job? (Score 0) 173

The FCC has, over the last couple of decades, gone a long way toward outsourcing radio regulation. Now, they're predominantly a finance agency conducting spectrum auctions and counting on competitors to police each other. Often, this actually works. Sometimes it doesn't. To be sure, they do have some field-based, rapidly-responding capability to identify interference, especially for (and between!) public safety users, and they occasionally use this to levy big fines to scare everyone else into compliance - I wouldn't want to absorb the typically $11K fine, personally. But their enforcement division is nothing like it used to be.

As far as what used to be called "type approval" (the pre-marketing certification that a device is compliant), it is now 100% outsourced. The fees for this run between $100K and $500K, depending on the complexity of the device and the section of the FCC regs you have to be compliant with (47CFR). 47CFR95 devices are cheap, 47CFR90 devices aren't. 47CFR5 devices can (usually) be self-certified, but they can't be sold.

So, unless Open Source drivers can be sold and operated under Part 5, and it's totally not evident to me that they can, then certification cost is going to mean that someone if going to have to pick a tiny handful of reference devices, certify some binary blobs, and call it done. My guess is that those someones would be Red Hat and quite possibly Lenovo - the one and only marketable Linux Laptop would perhaps be enough of a niche to pursue. In principle, someone like, say, Intel could certify a blob for a mezzanine card and sell the card to vendors, but bear in mind this means the antenna must be fixed onto the card and certified as a package.

Sorry to be such a downer...

Comment Re:Don't Panic! (Score 1) 68

If you're reading this article, you may also be interested in the E. H. Danner Museum of Telephony located on the grounds of Fort Concho National Historic Landmark in San Angelo, TX. While there, you might as well see the Robert Wood Johnson Museum of Frontier Medicine, also on the grounds. Don't go on a full stomach. And that's about all there is to do in San Angelo.

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