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Comment Re:Problem here is "racism" (Score 1) 915

Get off your high horse.

Where did someone say that the religions are the same, or compatible? The one comment I saw, which is I think the one you're referring to (since the parent post of your post doesn't talk about the sources of the religions), was that the *wizards* behind the three religions are the same.

Of course the religions are not compatible. That's why a lot of Muslims want Jews dead, Christians dislike Muslims and for the most part consider Jews harmless but misguided in matters of faith, etc. But, factually, the evolution of the three religions stems from the same original mythology, hence they are all three called Abrahamic religions, and they all developed around the same original God concept.

Comment Re:So when did... (Score 1) 433

It's more than the initial bootstrapping. Almost all cities have semi-exclusive deals with one "cable" and one "telco" provider. Some cities have done away with those exclusive deals, but there's still the non-trivial matter of getting permits and right of way to dig up and install fiber.

Even if the city is not contractually forbidden from granting those rights to new telecom companies, they might still not grant right-of-way on the basis that digging up streets or alleys is a nuisance... and anyway don't people already have telecom service? They don't need another option.

Keep in mind that the people making those decisions on the city level are like the politicians at the federal level who make fun of people who criticize SOPA. Except city politicians are more corrupt and dumber.

Comment Re:No, there is not (Score 1) 380

I understand that from the viewpoint of local violence being diminished in favor of legal process, but there are two caveats:

First, lack of regular protests, even if they would sometimes turn violent, tends to make the populace unwilling to protest anything. As long as the government keeps the lights on, water running, and internet tubes flowing, pretty much any violation of the constitution or the founding principles or anything else will go unchallenged. Sure, people may write nasty letters to politicians, and in the worst cases politicians might be voted out in the next election. But if the next guy is nearly the same, nothing is gained.

Second, although violence is abhored as a resolution to issues domestically, the U.S. has no problem instigating wars or coups abroad, even if those arguably increase the net violence in those countries.

Science

New Kind of Metal Theorized To Be In the Earth's Lower Mantle 117

slew writes "This article talks about a study accepted to Physical Review Letters which theorizes that iron oxide goes through an insulator/metal phase change with high temperature and pressure. Originally it was thought to be a crystalline structure change, but now apparently it is theorized to be a new type of metallic state. This discovery might offer new insight on how the earth's magnetic field operates."

Comment Re:Not so fast... (Score 2) 172

The standard recommendation I've seen is to overwrite at least 3, perhaps 5, 7, or even 9 times[0], often with a final all-zero overwrite[1] at the end (since an all-zero nominal image might discourage someone from looking harder, while a disk full of random-looking data can only result from a random overwrite or a full-disk encryption system).

The "kill it with fire" technique is more a question of speed and when you can afford to destroy disks. I've heard the NSA burns their disks, and Google physically mangles disks, but consider that those organizations are going to get rid of disks either when the device using them is past its useful lifetime, or when the disk starts failing. At that point the future value of keeping the disk around is low. It's more cost effective to use a quick method that prevents data recovery (of the desired level depending on threat model), rather than tying up computers and personnel in lengthy overwrite procedures when the disk is probably going to be thrown out anyway.

The reason for multiple overwrites is that if you look at absolute magnetic readings from the disk at each bit storage position, it's not digital. Instead of "1" or "0", you might see .998 or .005.

The one in-depth article I read a while back said that an overwrite moves the charge roughly 90% of the way to the opposite value. If a bit was "1" and is overwritten with "0", the new value would be 0.1 Subsequent overwrites similarly attenuate past data. Given disk error rates today, I think 90% is optimistically high.

For the sake of simplicity, if each overwrite pass changes the data value exactly 90% of the way from the current value to the target value, every bit on the disk is going to be either between 0 and 0.1 or between .9 and 1.0. More specifically, there are four possibilities for each bit. If the reading is close to the range 0.00 to 0.01, both the current and last image stored a zero. If the reading is close to the range 0.09 to 0.10, the current image is zero and the last image was a 1. Similarly for 0.90 to 0.91 and 0.99 to 1.00 ranges.

With a perfectly accurate magnetic detector and a HDD write mechanism that is perfectly accurate, and a perfectly linear and resilient magnetic layer on the disk, you could discover past images one by one... once you determine the last image logical value, you apply a function, possibly a linear map, to strip out the computer-visible layer and derive the exact magnetic reading as it would have been before the last overwrite. Repeat, wash, rinse...

The objective of overwriting several times is to push the magnetic differences caused by the last "real" stored data into the range where it's obscured by noise, either noise of the magnetic imager used to take raw magnetic readings, or much more likely, noise of the HDD writing mechanism (it isn't writing a perfect "1" value each time), or noise or imperfections of the magnetic substrate leading to imperfect magnetic storage.

I think recommendations for 35 overwrites, or even 9 overwrites, may be overestimating the capabilities of an adversary. Not because of anything the adversary does, but because of modern hard drives. Data is crammed into such small magnetic wells that the absolute magnetic readings are less consistent than ever before. Given the error rates of modern TB-sized disks, I would expect many blocks with unrecoverable (2+ bit errors per block) read errors upon reconstruction of even the second to last magnetic image. Repeating the process, I would expect errors to increase non-linearly. My WAG is that before 9 overwrites you're in a situation where even a perfect magnetic detector is reading only low-level noise from the drive. (I'm talking about noise from the non-perfect magnetic layer on the disk surface, and fluctuating magnetic field write strength from the drive head.)

[0] see, for instance, http://www.securityfocus.com/archive/1/310128

[1] An all-zero overwrite simply provides a surface layer of plausible deniability if nobody uses a magnetic imager and instead uses commodity hardware to check drive contents. A disk area filled with statistically random data, AFAIK, has only two causes: 1. a full-disk encryption program in a mode that doesn't use a header (e.g. Truecrypt's hidden containers), or 2) a secure overwrite pass. Both might draw unwanted attention in certain instances, where an all-zero disk might be mistaken for an unused drive.

Google

Why Google Is Disabling Kids' Gmail Accounts 228

theodp writes "The Washington Post's Elizabeth Flock managed to hold Google's feet to the fire and get an explanation of sorts for why it's making kids cry by disabling their Gmail accounts after years of use. Giving 12-year-olds access to Gmail — unless they are using Google Apps for Education accounts through their school — is proving to be as formidable a task for Google as making renewable energy cheaper than coal. But what about that viral 'Dear Sophie' commercial, asked Flock, in which a father creates a Gmail account for his baby daughter and uses it to send her photos, videos, and messages that chronicle her growing up? 'The implied understanding,' replied a Google spokesman, 'is that the girl in the story does not have access to the account, but that she will have access to it "someday."'"

Comment Re:How many threads like this? (Score 1) 334

I have one. It would frequently hang (over WIRED connection) for anywhere from a few mins to 15 minutes, then suddenly start working again. I monkeyed around with settings including disabling the AOSS and WPS stuff, and it stopped hanging. I don't know what specifically fixed it, but I'm using openwrt now so I'll never know. I suspect many of the "omg my wzr-hp-*300* router is broken" stories are just bugs in dd-wrt.

Comment Re:netgear n600 (wndr3800) (Score 5, Informative) 334

Oops, the dual band buffalo is wzr-hp-ag300h, not -nh.

Atheros:
Netgear wndr3700v1: 8MB flash, 64MB ram
Netgear wndr3700v2: 16MB flash, 64MB ram
Netgear wndr3800: 16MB flash, 128MB ram
Buffalo wzr-hp-g300nh: 32MB flash, 64MB ram (more chance of a lemon than the netgear wndr series)
Buffalo wzr-hp-ag300h: 32MB flash, 128MB ram

Broadcom
Netgear wndr4000: 8MB flash 64MB ram (BCM4718 ?)
Netgear wndr4500: 128MB flash 128MB ram (BCM4706 ?)
Linksys/Cisco e3000: 8MB flash 64MB ram (BCM4718 ?)
Linksys/Cisco e4200: 16MB flash 64MB ram (BCM4718 ?)

The ciscos from what I've read are very picky about nvram size.

Comment Re:netgear n600 (wndr3800) (Score 4, Informative) 334

wndr3700 or 3800.

They are atheros based, so there's the issue of occasional wireless drop-outs that may be fixed in openwrt snapshots (check svn changelog for late November '11), but that's a lot better than the wndr4500 and other broadcom SOC devices that are proprietary and difficult to reverse engineer.

Also, the wndr3700 is hard to brick, and easy to tftp to. There are similar atheros-based devices like the buffalo wzr-hp-g300nh (2.4GHz-only) and ag300nh (2.4 + 5 GHz), but they're harder to flash and maybe have quality control problems on transmit power (some people complain).

Media

Ask Slashdot: Best Camera For Getting Into Photography? 569

An anonymous reader writes "I've managed to go my entire adult life without owning an actual camera. I've owned photosensors that were shoehorned into various other gadgets, but I've gotten to the point where the images produced by my smartphone aren't cutting it. My question: what camera would you recommend for getting into basic photography? I don't mean that in the sense of photography as a hobby or a profession, but simply as a method for taking images — of friends, family, and projects — that actually look good. That's a subjective question, I know, but I suspect many of you have a strong grasp of price versus performance. For example, when I'm picking a new video card, it's easy to figure out which cards are the best deals for a given price point — then I just have to pick a price I'm comfortable with. I figure a decent camera will run me a few hundred dollars, which is fine. But I don't have the expertise to know at what point spending more money isn't going to do me, as a camera newbie, any good. Any thoughts?"

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