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Comment Re:Perfect for the hobbyist, my ass! (Score 2) 81

Bit-banging a USB interface is about as smart as bit-banging an Ethernet interface. Sorry, but both were architected to be implemented in hardware. Once you accept that, both are perfectly fine hobbyist interfaces.

If you choose a micro without the requisite hardware support, your life will be very, very difficult.

Comment Yes, it's time. (Score 5, Interesting) 702

Kill the penny.
Kill the Nickel.
Keep the dime - the smallest coin will now have the smallest value.
Kill the quarter
Create a new $0.50 piece a bit bigger than a dime, maybe a bit smaller than a penny.
Create a new $1.00 piece about the size of a nickel, maybe slightly larger.
Create a new $5.00 piece about the size of a quarter.

To avoid confusion between new/old, change something mechanical - put a hole through the middle, or make them all octagonal or decagonal.

If you're worried about cost, make the dime and half out of Aluminum. We've given up the concept of any actual value in our currency, so it's time to give up the artificial weight that made them feel like silver.

Don't try to differentiate them by color. As the Sacajawea dollar taught us, after a few years in grubby fingers and rattling around in pockets, all coins start to have the same surface color.

We end up with rationally sized coins, getting bigger as the value gets bigger. We get rid of the small valued paper money, which is also expensive to print/replace.

Comment Re:why? (Score 4, Informative) 401

Well, the Bell System WAS a government created monopoly, which fought tooth and nail against every attempt to nibble away at any part of it. All the government had to do to dismantle it was to repeal the laws the prevented any competition.

Standard Oil, on the other hand, was a market created monopoly where the government had to take aggressive action to dismantle it.

Comment Re:Use pre-shared keys (Score 1) 86

Do you understand the difference between public key cryptography and symmetric key cryptography? Can you succinctly explain why comparing Diffie-Helman to AES is like comparing an apple to a metamorphic rock?

Answer those questions, my son, then feel free to come back and comment on matters of encryption. Until then, STFU.

Comment Re:So I know something about this.... (Score 1) 242

So is it OK if I drop by and hand you my Galaxy S6, and start a timer to see how long it takes you to break in? I'd guess 8-10 hours of solid work for you, someone who appears knowledgeable in this area. That qualifies at least as "very difficult" to me, though perhaps I overstated it with "extraordinarily difficult".

You seem quite knowledgeable, and I find no fault with your analysis and subsequent posts, other than the quibble with the level of effort needed.

Comment So I know something about this.... (Score 5, Interesting) 242

Finally, a slashdot topic where I can be informative. Disclaimer: I work in the industry building fingerprint sensors.

Fingerprints aren't perfect security. As so many others have pointed out, you leave them everywhere. That doesn't mean that they're not useful.

1. It's extraordinarily difficult to create a fingerprint spoof from a latent print. Yes, there are people who can do it - I can do it - but it's not easy. Notice on the videos of breaking into the iPhone 5s or 6 that latent prints are taken from a single fingerprint placed carefully on a squeaky clean screen. On your average phone, not so much. Someone who picks up my phone off the seat in a subway will be incapable of breaking in - unless I've just cleaned the screen with windex and carefully placed my fingerprint on it.

2. A fingerprint on a phone makes an excellent two-factor authentication system. The average hacker in east Elbonia can't break fingerprint security - because they don't have my phone or my fingerprint.

Perfect? No, but strong? Yes.

Comment Another Corporate rape of the commons (Score 3, Insightful) 142

This is another in a long line of corporate taking.

They want to take a huge swath of public space (the space between 200 and 400 feet across the ENTIRE UNITED STATES) for free, for their benefit and the benefit of the rich who can afford to pay for this-hour delivery, and deliver nothing back to the vast majority of the population.


Comment Re:Wrong solution, wrong problem (Score 1) 233


File timestamps should be in linear time (GPS, TAI, whatever).

What gets displayed to you as a human is in your local time - timezone + planetary adjustment - so it matches the time on the wallclock. Do you as a human really care about the LSB in the file time? For those rare times when you do, you'll use linear time.

Comment Similar to everyone else... (Score 1) 557

Looking out over the next couple of years, 802.11ac at 2.4/5 GHz would be the wireless standard that you need to install - any electronics you buy in that time are going to want that. Infrastructure needs for this are pretty well understood. After that, you'd want to be able to install 802.11ad - infrastructure to that is a bit more difficult. To support it, you'll need 1 or 2 wireless routers per room with a good viewing angle. This, to me, would say that I'd like power and wired network ports in the upper corner of every room. When I built an addition onto my house 10 years ago, the contractor thought I was crazy wanting a power outlet and network tap in the upper corner of each bedroom closet - but it's been an excellent place to locate 5 GHz routers. Adding future nanny cams, microphones for voice control of the house, etc becomes easy with such well located network access points.

Assume that the data provider entries to your house (phone company, cable company, satellite service, TV antenna) need to be provided by you. Run power to the locations, install a good ground rod at each location, run conduit from the locations to your wiring closet. If you hate everyone nailing their own ugly demarc box to your exterior wall, design an acceptable utility entrance that will hide them.

I think Cat 6 and quad-shield RG-6 to one or two wallplates in every room makes sense. For the foreseeable future, broadcast TV (either cable or satellite) is going to get distributed around your house on Coax, not Ethernet, and short of going to Fiber, Cat-6 is about as good as network wiring is going to get. It's also hard to imagine network speeds really needing to be above the 10 Gbit level that you can get with Cat-6. How many 4K video streams do you really expect to ever need on a single port? I don't know that I'd spend the extra money to run conduit to every room - perhaps only to the one or two main media centers of the house. You know that you'll kick yourself if you decide to open up a datacenter in your spare bedroom and need to install multiple single-mode fibers to the rack of raspberry-pi sized servers you install in there, but we can't have everything.

Wire all the doors and windows in the house with alarm wiring, even if you don't plan on installing a system. Make it hidden - magnetic switches embedded in the frames with magnets mortised into the door or window. Run two to every door/window, so a broken wire isn't a critical failure. If you're into christmas lights, prewire outlets under the eaves so you don't end up with extension cords all over the place. It's a good place to install a network jack also, in case you decide to install security lights/cameras.

You didn't ask about environmental design, but I agree with a lot of the posters - spend some time to minimize heating and cooling costs and maximize comfort. Recognize that most HVAC duct design is intended for minimum installed cost, not necessarily minimum 10-year operational cost or comfort. Consider humidity control - for me in Phoenix, it means humidifiers in the initial plan; for someone in Florida, it might mean dehumidifiers in the initial plan. Consider allergen control - a lot easier to implement if it's considered up front. Consider a zoned system with possibly multiple thermostats - in a big house, being able to completely turn off HVAC to unused rooms (rather than shutting the door) can have significant savings.

Consider asking the plumber and electrician to go outside their "install it as cheaply as possible" mindset, and make the systems more user-friendly. As an example, it might cost a few hundred dollars more to wire the house rationally (each circuit breaker controlling outlets in the same room) rather than lowest cost (minimize wire length, even if it means a circuit breaker controls a few outlets in three different rooms, or a single room has three different breakers so you never know which one to throw to turn off power to a specific outlet). It might cost a few hundred dollars more to plumb the house rationally - as a star, rather than point-to-point (case in point: in my master shower, the cold water comes from the water entry point a few feet away, but the hot water goes from that water entry point all the way across the house to the hot water heater, then comes all the way back (after a detour through the second bathroom) to the shower. Any disturbance in water flow anywhere in the house has a disproportionate impact on the hot water flow). Rather than a wiring closet, I'd dearly love to have a "plumbing closet" with cold and hot water manifolds that distribute water to each room (kitchen, bathroom, shower) and individual shutoffs. Ask the plumber to fully insulate all hot water pipes and add a hot water recirculation system if you're putting in central hot water (i.e. solar). Make sure the dishwasher can get immediate hot water - it really sucks if it always fills with water that has cooled in the pipes.

Unfortunately, there really isn't a DC voltage standard for lighting yet. 20 years from now, when solar electric and battery packs are standard, there will presumably be a 24V or 48V standard for house lighting that doesn't require DC->AC conversion, then AC->DC conversion inside the lighting system as we have now. You might want to consider designing in an area near your solar panels so you can intall substantial battery system 5-10 years down the road, however.

Comment Dust and Bugs (Score 1) 253

        Everyone is going off on the humidity - that's the least of your problems. Assuming that it's a non-condensing atmosphere (i.e. fog), the warmth in the box will keep any additional condensation from happening and the box will run fine.

        High temperature may be an issue. I live in Phoenix, and putting a server outside is, well, not the worlds best idea. If you live somewhere where the high temps in summer are less than 90 degrees, you're probably fine from a temperature standpoint.

        Bugs and dust will be the big problems. Solve those, and you'll be good to go.

        I've built boxes before that housed computers in my garage. I made'em out of plywood, made them reasonably airtight, and put muffin fans on one end, pulling outside air through a high-quality air filter (, and put exhausts (wire-covered) on the other side. Worked fine through several summers where the garage got up into the high 90's, didn't have any problems with bugs or dust or component failures.

        The two or 4 disk NAS boxes are a great size for this kind of thing. My current home server is an ancient 4-bay Buffalo Terastation case, that I ripped the motherboard out of and replaced it with a low-power 12-volt motherboard (ASRock Q1900DC-ITX) and installed FreeNas on it. Works great, and something like that would work remarkably well for your needs.

        Good luck, and don't listen to the crybabies.

Comment Re:Coal kills people in different ways (Score 2) 224

Well, a quick Google search shows you wrong - there is well-documented research into the amount of radioactivity in coal plant emissions. As an example, USGS:
and others.

Is it an issue? The released radioactivity from a coal plant is up to 100 times that of a nuclear power plant - but those emissions are so ludicrously low that you can treat it as (100 * 0) = 0. There really isn't a health issue from the emissions.

Mercury, Sulfur, Nitrogen, sure - Radioactivity, not so much.

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