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Jan "Starbug" Krissler, the Chaos Computer Club researcher who broke the fingerprint reader security on the new Iphone, had given a long interview to Zeit Online explaining his process and his thoughts on biometrics in general. The CCC's Alex Antener was good enough to translate the interview for us; I've included some of the most interesting bits after the jump.

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An anonymous reader sends this news from Al-Jazeera:
"BP has been accused of hiring internet 'trolls' to purposefully attack, harass, and sometimes threaten people who have been critical of how the oil giant has handled its disaster in the Gulf of Mexico. The oil firm hired the international PR company Ogilvy & Mather to run the BP America Facebook page during the oil disaster, which released at least 4.9 million barrels of oil into the Gulf in what is to date the single largest environmental disaster in U.S. history. The page was meant to encourage interaction with BP, but when people posted comments that were critical of how BP was handling the crisis, they were often attacked, bullied, and sometimes directly threatened. ... BP's 'astroturfing' efforts and use of 'trolls' have been reported as pursuing users' personal information, then tracking and posting IP addresses of users, contacting their employers, threatening to contact family members, and using photos of critics' family members to create false Facebook profiles, and even threatening to affect the potential outcome of individual compensation claims against BP."

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Original author: 
Soulskill

coop0030 writes "Feel like someone is snooping on you? Browse anonymously anywhere you go with the Onion Pi Tor proxy. This is fun weekend project from Adafruit that uses a Raspberry Pi, a USB WiFi adapter and Ethernet cable to create a small, low-power and portable privacy Pi."

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Original author: 
Todd Hoff

"It’s all a numbers game – the dirty little secret of scalable systems"

Martin Thompson is a High Performance Computing Specialist with a real mission to teach programmers how to understand the innards of modern computing systems. He has many talks and classes (listed below) on caches, buffers, memory controllers, processor architectures, cache lines, etc.

His thought is programmers do not put a proper value on understanding how the underpinnings of our systems work. We gravitate to the shiny and trendy. His approach is not to teach people specific programming strategies, but to teach programmers to fish so they can feed themselves. Without a real understanding strategies are easy to apply wrongly.  It's strange how programmers will put a lot of effort into understanding complicated frameworks like Hibernate, but little effort into understanding the underlying hardware on which their programs run.

A major tenant of Martin's approach is to "lead by experimental observation rather than what folks just blindly say," so it's no surprise he chose a MythBuster's theme in his talk Mythbusting Modern Hardware to Gain "Mechanical Sympathy." Mechanical Sympathy is term coined by Jackie Stewart, the race car driver, to say you get the best out of a racing car when you have a good understanding of how a car works. A driver must work in harmony with the machine to get the most of out of it. Martin extends this notion to say we need to know how the hardware works to get the most out of our computers. And he thinks normal developers can understand the hardware they are using. If you can understand Hibernate, you can understand just about anything.

The structure of the talk is to take a few commonly held myths and go all MythBusters on them by seeing if they are really true. Along the way there's incredible detail on how different systems work, far too much detail to gloss here, but it's an absolute fascinating talk. Martin really knows what he is talking about and he is a good teacher as well.

The most surprising part of the talk is the counter intuitive idea that many of the devices we think of as random access, like RAM, HDDs, and SSDs, effectively become serial devices in certain circumstances. A disk, for example, is really just a big tape that's fast. It's not true random access. Keep on reading to see why that is...

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Original author: 
Todd Hoff

It's not often you get so enthusiastic a recommendation for a paper as Sergio Bossa gives Memory Barriers: a Hardware View for Software Hackers: If you only want to read one piece about CPUs architecture, cache coherency and memory barriers, make it this one.

It is a clear and well written article. It even has a quiz. What's it about?

So what possessed CPU designers to cause them to inflict memory barriers on poor unsuspecting SMP software designers?

In short, because reordering memory references allows much better performance, and so memory barriers are needed to force ordering in things like synchronization primitives whose correct operation depends on ordered memory references.

Getting a more detailed answer to this question requires a good understanding of how CPU caches work, and especially what is required to make caches really work well. The following sections:

  1. present the structure of a cache,
  2. describe how cache-coherency protocols ensure that CPUs agree on the value of each location in memory, and, finally,
  3. outline how store buffers and invalidate queues help caches and cache-coherency protocols achieve high performance.

We will see that memory barriers are a necessary evil that is required to enable good performance and scalability, an evil that stems from the fact that CPUs are orders of magnitude faster than are both the interconnects between them and the memory they are attempting to access.

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Original author: 
Aaron Souppouris

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Security researchers have discovered a way to push software onto an iOS device using a modified charger. The team at Georgia Institute of Technology says its charger was able to upload arbitrary software to an iOS device within one minute of it being plugged in. According to the researchers, "all users" are at risk, as the hack doesn't require any user interaction. Hackers are even capable of hiding the applications, so they don't show up in the device's app list. It's not clear if the charger is able to upload malicious code — Apple's iOS devices, by default, are "sandboxed" and will only install and run properly signed apps — but this is a worrying development regardless.

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Original author: 
Adi Robertson

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To call something "propaganda" is to connote a laughably unsubtle attempt at mind control, from the kind of nasty stereotypes mocked in BioShock Infinite to a hilariously redubbed North Korean propaganda video that many thought was real — precisely because we expect such attempts to be ham-fisted and idiotic. At The Guardian, Eliane Glaser argues that we should be looking instead at how behavioral science, advertising, and even memes can nudge us in certain directions. "The notion that propaganda is always a state-run, top-down affair provides a cloak for our complicity," she writes. "Social media's veneer of openness and people-power exemplifies western propaganda's habit of masquerading as its opposite."

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Original author: 
Jeff Blagdon

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In 2002, a startup named SawStop demonstrated a table saw that could miraculously cut through wood, but stop itself dead (video below) as soon as its spinning blade touched skin. The mechanism was incredibly effective, heading off some 2,000 of the nearly 300,000 table-saw-related emergency room visits that occurred in the US since the company sold its first saw. But despite SawStop’s effectiveness, the big tool companies still haven’t added it to their products. Meanwhile, saw-related injuries result in some $2.3 billion in medical bills, lost wages, and other societal costs every year. Fair Warning investigates why the power tool industry has so far failed to license the SawStop technology or implement its own alternative. "If the...

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Original author: 
Jon Brodkin


The Arduino Due.

Arduino

Raspberry Pi has received the lion's share of attention devoted to cheap, single-board computers in the past year. But long before the Pi was a gleam in its creators' eyes, there was the Arduino.

Unveiled in 2005, Arduino boards don't have the CPU horsepower of a Raspberry Pi. They don't run a full PC operating system either. Arduino isn't obsolete, though—in fact, its plethora of connectivity options makes it the better choice for many electronics projects.

While the Pi has 26 GPIO (general purpose input/output) pins that can be programmed to do various tasks, the Arduino DUE (the latest Arduino released in October 2012) has 54 digital I/O pins, 12 analog input pins, and two analog output pins. Among those 54 digital I/O pins, 12 provide pulse-width modulation (PWM) output.

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