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Submission + - An Algorithm For Better Password Checking

della writes: Password checkers — those things that tell you whether your password is strong or not — are good: various studies have found that they make users choose better passwords. Unfortunately, nowadays attackers use probabilistic strategies based on natural language processing to guess passwords earlier, and most checkers consist of heuristic rules that don't reflect well probabilistic attacks. To do better you could in theory simulate the attack, but if your password is not that bad, that would be very expensive or just unfeasible.
In a paper I wrote with Maurizio Filippone and presented at ACM's CCS conference, we show how you can take an attack model and a password, and through a simple formula come up quickly with a reliable estimation of how many guesses that attack would need to guess the password. You can use this to roll a better password checker, or — as we've also done in the paper — to compare different attacks. The MIT Technology Review also covers our work.

Submission + - New Hubble Release Puts Another Nail In The Coffin Of Dark Matter's Competitors

StartsWithABang writes: When it comes to the structure of the Universe — forming the galaxies, clusters, and Universe as we see it — the normal matter we know of simply isn’t enough. Given our best-understood laws of physics, including Einstein’s general relativity, what we see of galaxies and the Universe in general simply doesn’t match up to our predictions. The simplest solution, arguably, is to just add a new ingredient: a new form of matter, a dark matter if you will. But a counterargument is that we’ve got the laws of gravity wrong, and that no new matter is necessary. There’s only one way to settle an argument like this: with data, evidence and the full suite of observations at our disposal. The newest Hubble release, along with four other independent lines of evidence, rule out modifications of gravity and leave dark matter as the only option standing.

Astronomers Solve the Mystery of 'Hanny's Voorwerp' 123

KentuckyFC writes "In 2007, a Dutch school teacher named Hanny van Arkel discovered a huge blob of green-glowing gas while combing though images to classify galaxies. Hanny's Voorwerp (meaning Hanny's object in Dutch) is astounding because astronomers have never seen anything like it. Although galactic in scale, it is clearly not a galaxy because it does not contain any stars. That raises an obvious question: what is causing the gas to glow? Now a new survey of the region of sky seems to have solved the problem. The Voorwerp lies close to a spiral galaxy which astronomers now say hides a massive black hole at its center. The infall of matter into the black hole generates a cone of radiation emitted in a specific direction. The great cloud of gas that is Hanny's Voorwerp just happens to be in the firing line, ionizing the gas and causing it to glow green. That lays to rest an earlier theory that the cloud was reflecting an echo of light from a short galactic flare up that occurred 10,000 years ago. It also explains why Voorwerps are so rare: these radiation cones are highly directional so only occasionally do unlucky gas clouds get caught in the crossfire."

OpenSSH 5.4 Released 127

HipToday writes "As posted on the OpenBSD Journal, OpenSSH 5.4 has been released: 'Some highlights of this release are the disabling of protocol 1 by default, certificate authentication, a new "netcat mode," many changes on the sftp front (both client and server) and a collection of assorted bugfixes. The new release can already be found on a large number of mirrors and of course on www.openssh.com.'"

Comment It's Not About the Games! (Score 1) 173

If done right, the game or whatever just serves as an engagement and recruiting tool. The important bit is then using the platform to introduce problem solving and programming learning opportunities and then relating that back to the non-gaming IT world.

In my case, I teach the first course in Computer Engineering, and I use the Wii Controller as the data source. Check out http://www.youtube.com/watch?v=tPCBfyQP4eE to see a lab where students use the wii remote in a foam football to measure the distance it fell in real time in an 8+ meter drop.

This draws on their physics, math, and learning how to structure solutions to a problem nicely.

Comment Much Earlier Article on Xerox Systems (Score 2, Interesting) 153


Basically, 9 years ago we showed some remarkably embarassing features in Xerox multifunction printer/copiers/faxes. Including SNMP access to plaintext passwords!

I wonder how many of these "features" are still there.

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