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Comment Re: Why not allow the update into the repos? (Score 1) 126

And how, prey tell, do you expect the developers to sign their packages with everybody else's private keys? If they do that the update will fail, because the package manager isn't going to install a package from an Ubuntu repository that isn't signed by Cannonical's private key, for example.

Comment Re:Excuse me while.. (Score 1) 101

"... for those that were stupid enough to think that something electronic and stored in a common format over a common communications medium was secure.

Stupid enough? I hate to break it to you, but most if not all secure systems work in exactly the way you decry to be "stupid". Maybe you've heard of SSL?

Comment Re:No need to read TFA ... (Score 1) 346

Yeah, to have local governments build and maintain networks that serve all comers, commercial and private, while recovering all costs from usage-based user fees would be, dare I say it, socialism! Next thing you know, the socialists will even propose to have local governments build and maintain roads for the public good!

Comment Re:How do they get around the altitude limit? (Score 2) 48

The problem is ITAR - International Traffic in Arms Regulations. The idea was to keep cheap civilian receivers from being used in ICBMs. For that reason, there's an altitude and velocity limit, but the language was ambiguous. Some manufacturers interpreted it as an altitude AND a velocity, others interpreted it as an OR. The latter create the problem.

Comment Re:Ion Thruster (Score 1) 48

Your explanation is pretty much correct. But getting higher with a balloon is literally exponentially more difficult because that's exactly how the density of the atmosphere decreases with height. Your balloon has to expand exponentially as it climbs, and exponentials are not functions to be trifled with. The vertical distance over which the atmospheric density decreases to 1/e of its starting value is the "scale height", and for the earth it is an average of 7.6 km (it varies with temperature). But you can see that just getting to 30 km (100,000') is already about 4 scale heights, with your balloon expanding by a factor of e^4. Even that much is harder than it looks because the balloon expands as rises, and the gas inside cools adiabatically, causing its density to increase. Even in thermal equilibrium with the air outside, that air is awfully cold, which doesn't help decrease the lifting gas density. I think 100 km is completely out of the question. That's the Karman line, and it was chosen as roughly the altitude where an airplane could not generate enough lift to hold itself up even if it was going at orbital velocity. That's not a lot of air.

Comment Re:10,000 MPH to get into orbit (Score 1) 48

Not quite. Assuming "100k" means "100 km", conventionally chosen as the edge of space, getting there going straight up from 30 km (an easy weather balloon altitude) requires an upward force greater than the weight of the payload. Anything less and you'll just fall back to earth. If you do this with a rocket (what else would you use?) you will find that doing it slowly is *very* expensive in propellant. In rocketry this is called "gravity loss", and it's one of the reasons rockets don't just go straight up to space even when the intent is to escape the earth. They fly an arched path known as a 'gravity turn': just enough altitude is gained to reduce air drag to an acceptable level while you try to build up horizontal velocity as fast as you can. The less time you spend with your rocket anything but horizontal, the lower your gravity losses will be and the more hard-earned rocket impulse you can devote to getting orbital velocity and *staying* in space.

Submission + - Details of iOS and Android Device Encryption

swillden writes: There's been a lot of discussion of what, exactly, is meant by the Apple announcement about iOS8 device encryption, and the subsequent announcement by Google that Android L will enable encryption by default. Two security researchers tackled these questions in blog posts:

Matthew Green tackled iOS encryption, concluding that at bottom the change really boils down to applying the existing iOS encryption methods to more data. He also reviews the iOS approach, which uses Apple's "Secure Enclave" chip as the basis for the encryption and guesses at how it is that Apple can say it's unable to decrypt the devices. He concludes, with some clarification from a commenter, that Apple really can't (unless you use a weak password which can be brute-forced, and even then it's hard).

Nikolay Elenkov looks into the preview release of Android "L". He finds that not only has Google turned encryption on by default, but appears to have incorporated hardware-based security as well, to make it impossible (or at least much more difficult) to perform brute force password searches off-device.

Comment Re:Jamming unlinced spectrum is illegal? (Score 1) 278

Sorry, but the rules make no distinction between licensed and unlicensed spectrum. If you deliberately interfere with someone else's radio communications, you are breaking the rules.

Marriott's reply is laughable. It might work on unsophisticated readers but not anyone who knows anything about WiFi. They said they wanted to "protect" their guests against "rogue" access points. Well, if those "rogue" access points were spoofing Marriott's own SSID, they might have a point. But I certainly don't set my own portable hotspot SSID to that of any hotel. It's set to something quite unique, and it's encrypted. Nobody is going to mistake it for a hotel's network, much less actually associate with it.

Comment Re:Why is 1984 in this poll? (Score 1) 410

Although 1984 shows up on the list of challenged classics, there is only one challenge listed -- someone in Jackson County, Florida in 1981 thought that it was "pro-communist and contained explicit sexual matter".

Fahrenheit 451 isn't even on that list, though it has been banned from specific schools in the past.

Comment Re:At home too (Score 1) 185

You''re a troll. Plain and simple. I have been installing Linux on computers for more than 15 years. I have yet to be unable to get a computer to run flawlessly with the exception of suspend / resume, and that hasn't been a problem for the last couple of years also.

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