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Comment Lots of room for methodology issues. (Score 2) 307

The lack of accidents and crime are more likely related to a general trend in crime going down from before they started turning off the lights. ... Give me at least one full year worth of data so I can compare it to the prior year, and have half of the country keep their lights on so It can be compared to the same time frame as well.

Hear, hear!

There's lots of room for methodology errors. Here's another:

Comparing murder rates between Great Britain and the US is complicated by differences in reporting. The US bumps the murder stat when there is a body and evidence of foul play. G.B. bumps it when they have a conviction.

Do they do that with other crime? If so, stable stats in the absence of street lighting might mean that any rise in crime is compensated for by a fall in identifying, apprehending, and convicting the criminals responsible. (Indeed, turning off the lights might easily result in LOWERED crime statistics at the same time it was causing a drastic increase in actual crime.)

Comment Re:And the NSA? (Score 1) 223

Actually, they probably included a few big wrenches to assemble some of the rack systems, so they probably have the tools to break even 1024 bit encryption.

When you say "1024-bit encryption" you're talking about RSA, which is a completely different problem. 1024-bit RSA are too small to be used today and should be replaced.

2048-bit RSA keys, however, are roughly equivalent in security against brute force to a 112-bit symmetric key, and will be secure against anyone for quite some time. 3072-bit RSA keys are equivalent to a 128-bit symmetric key. Excascale, even yottascale, computers won't touch them.

But everyone really should be moving away from RSA anyway. ECC is better in virtually every respect. To get 128-bit security (meaning equivalency to 128-bit symmetric key), you only need a 256-bit EC key.

Comment Re:How do they fare in colder climates? (Score 1) 904

Range suffers a bit, not so much because the batteries are affected by cold, but because you use some juice to heat the cabin. As far as performance on snow, they're great. Their center of gravity is low, front wheel drive and the power applied to the wheels is finely controllable.

I drive my Nissan LEAF to the ski resort almost every morning during the winter.

Comment Re:Doubtful (Score 1) 904

What complicates this is that whether or not an electric car is cheaper depends heavily on your driving -- and whether or not an electric car is feasible depends on your driving. TOC also depends on the cost of fuel and electricity. When I ran the numbers for myself a few years ago my break-even for a Nissan LEAF was three years, with the federal and state tax credits, or eight years without. That was without taking into consideration the difference in maintenance costs since I didn't know how to estimate them. I did not, however, predict the drop in gas prices. I haven't re-run the numbers, but I expect the lower price of gasoline would push those break-even points out 2-3 years.

Comment What hospital is that? (Score 1) 54

I'm an anesthesiologist. I put people to sleep for cardiac surgery. My hospital does around 400-500 hearts a year... and we don't kill any dogs.

What hospital is that? I'll want to avoid it if I ever need heart surgery.

Seriously: How does your cardiac unit's mortality and morbidity rate stack up against those of hospitals where practice surgery on live animal, models, at least where the surgeon is new to the procedure, is more common?

Comment Re:And the NSA? (Score 1) 223

Probably none at all. If you want to break today's encryption/hashing algorithms you would probably be using ASICs if not those then FPGAs with GPU compute being your last choice.

ASICs, FPGAs and GPUs are all utterly, utterly inadequate to attack today's encryption and hashing algorithms. Unless you have not only tens of billions of dollars but also don't mind waiting millions of years. http://tech.slashdot.org/comme....

Comment Re:And the NSA? (Score 1) 223

For that, you would be using custom ASIC hardware, and lots of it.

No, for that you just laugh at the guy asking you to do it, and look for ways to steal the key, rather than brute forcing it. Even if an ASIC solution gets to way beyond exascale, say to yottascale (10^6 times faster than exascale), you're still looking at on the order of a million years to recover a single 128-bit AES key, on average.

Brute force is not how you attack modern cryptosystems. More detail: http://tech.slashdot.org/comme...

Comment Re:And the NSA? (Score 5, Informative) 223

What would the existence of an exascale supercomputer mean for today's popular encryption/hashing algorithms?

Nothing, nothing at all.

Suppose, for example that your exascale computer could do exa-AES-ops... 10^18 AES encryptions per second. It would take that computer 1.7E20 seconds to brute force half of the AES-128 key space. That's 5.4E12 years, to achieve a 50% chance of recovering a single key.

And if that weren't the case, you could always step up to 192 or 256-bit keys. In "Applied Cryptography", in the chapter on key length, Bruce Schneier analyzed thermodynamic limitations on brute force key search. He calculated the amount of energy required for a perfectly efficient computer to merely increment a counter through all of its values. That's not to actually do anything useful like perform an AES operation and a comparison to test a particular key, but merely to count through all possible keys. Such a computer, running at the ambient temperature of the universe, would consume 4.4E-6 ergs to set or clear a single bit. Consuming the entire output of our star for a year, and cycling through the states in an order chosen to minimize bit flips rather than just counting sequentially, would provide enough energy for this computer to count through 2^187. The entire output of the sun for 32 years gets us up to 2^192. To run a perfectly-efficient computer through 2^256 states, you'd need to capture all of the energy from approximately 137 billion supernovae[*]. To brute force a 256-bit key you'd need to not only change your counter to each value, you'd then need to perform an AES operation.

Raw computing power is not and never will be the way to break modern crypto systems[**]. To break them you need to either exploit unknown weaknesses in the algorithms (which means you have to be smarter than the world's academic cryptographers), or exploit defects in the implementation (e.g. side channel attacks) or find other ways to get the keys -- attack the key management. The last option is always the best, though implementation defects are also quite productive. Neither of them benefit significantly from having massive computational resources available.

[*] Schneier didn't take into account reversible computing in his calculation. A cleverly-constructed perfectly-efficient computer could make use of reversible circuits everywhere they can work, and a carefully-constructed algorithm could make use of as much reversibility as possible. With that, it might be feasible to lower the energy requirements significantly, maybe even several orders of magnitude (though that would be tough). We're still talking energy requirements involving the total energy output of many supernovae.

[**] Another possibility is to change the question entirely by creating computers that don't operate sequentially, but instead test all possible answers at once. Quantum computers. Their practical application to the complex messiness of block ciphers is questionable, though the mathematical simplicity of public key encryption is easy to implement on QCs. Assuming we ever manage to build them on the necessary scale. If we do, we can expect an intense new focus on protocols built around symmetric cryptography, I expect.

Comment Re:Animals (Score 1) 54

I'm an anesthesiologist. I put people to sleep for cardiac surgery. My hospital does around 400-500 hearts a year... and we don't kill any dogs.

So maybe I'm not up to date, or things are/were different in research hospitals.

My personal info was based on stories told by my mother, in about the '60s, when she was a special duty RN at the University of Michigan hospital, often handling cardiac recovery.

My favorite was the one where the UofMich hospital cafeteria, which had been purely open seating, established separate rooms for the staff to eat after an incident where patients' families overheard, and were traumatized by, a cardiac surgeon's response to a question. Asked how his operations the previous day had gone (referring to his experimental and/or practice surgery on a collie and another dog), he said "The blonde lived but the old bitch died."

The kids and adopted dogs story was from my wife. The surgeon in question was Dr. Albert Starr in (at least) the '60s through '80s. He was at St. Vincent's and also flew, with his team, to operate at a number of other west coast hospitals, university and otherwise.

Comment Animals (Score -1) 54

A possible solution would be better simulations so that a student can learn by doing. I think it is a very different than working on a cadaver or simulated patient using conventional methods.

You obviously aren't familiar with surgical departments or you wouldn't have missed practice surgeries on live animals.

For instance: a typical cardiac surgeon, shortly before EACH operation on a human patient, does a practice operation of the same procedure on a live dog.

One pediatric cardiac surgeon was much beloved by his patents and their families, because (with parental permission) he would let the kid adopt the practice dog, rather than sending it to be destroyed. The kid would wake up from surgery with the new puppy beside him, with the same bandages, etc. (and a day or so farther along in recovery). The dog having been through the same procedure and having helped save the kid's life even before they met made for very strong owner/pet bonds. (There's always a live, healthy, practice dog. If the dog dies (or is severely damaged) the assumption is that the procedure failed. You DON'T do a procedure on a human if it just killed a dog. You analyze, adjust the procedure, and repeat until success.)

Getting skills up does NOT require, or usually involve, a lot of practice on JUST advanced simulations, cadavers or, live patients. The live patients are just the last step, when the skills are already finely honed, and the animal models provide immediate feedback, real situations, and automatically correct modelling of mammalian life processes.

Comment Re:"...the same as trespassing." (Score 1) 1197

Not true, Indiana allows deadly force in defense of property, and there is no duty to retreat. And it includes your vehicle when away from home.

Cite?

I think you're talking about Indiana's Castle Doctrine law, which gives you the right to assume that you're threatened with death if someone breaks into your house or car (some states also include place of business). But the authorization is for self-defense, not defense of property. The Castle Doctrine just means that the law automatically assumes that you were at risk of death or serious injury in those locations, and you don't have to justify it.

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