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Measuring the Speed of Light With Valentine's Day Chocolate 126

Cytotoxic writes "What to do with all of those leftover Valentine's Day chocolates? — a common problem for the Slashdot crowd. The folks over at Wired magazine have an answer for you in a nice article showing how to measure the speed of light with a microwave and some chocolate. A simple yet surprisingly accurate method that can be used to introduce the scientific method to children and others in need of a scientific education."
Microsoft

Submission + - Microsoft warns of TLS/SSL flaw in Windows (arstechnica.com)

Rish writes: Microsoft has issued Security Advisory (977377) to address a publicly disclosed vulnerability in the Transport Layer Security (TLS) and Secure Sockets Layer (SSL) protocols. The TLS and SSL protocols are implemented in several Microsoft products, both client and server. Currently Microsoft has concluded that it affects all supported versions of Windows: Windows 2000 SP4, Windows XP (32-bit and 64-bit), Windows Server 2003 (32-bit and 64-bit), Windows Vista (32-bit and 64-bit), Windows Server 2008 (32-bit and 64-bit), Windows 7 (32-bit and 64-bit), and Windows Server 2008 R2. Microsoft says it will update the advisory as the investigation progresses.

This warning should not be confused with the 13 Security Bulletins fixing 26 vulnerabilities Microsoft released today on this month's Patch Tuesday; the company is simply stating that it is investigating the flaw. Microsoft also makes sure to note that since the issue implicates an Internet standard, the company recognizes that it affects multiple vendors and is working on a coordinated response with its partners in the Internet Consortium for Advancement of Security on the Internet (ICASI).

Comment Re:Buy a Pre (Score 2, Interesting) 684

T-Mobile eventually intentionally put a stop to unsigned clients

Rubbish. I don't know what you're doing wrong, but I use an AT&T-branded Blackberry 8310 with my T-mobile account. T-mobile doesn't have a 8310, so I can assure you that T-mobile not only allows "unsigned clients" (whatever the fuck that means; unlocked? different vendor-id?), but their telephone support helped me do it.

Comment Re:dunno exactly (Score 1) 173

LLVM can (and is) used to subvert the GCC's GPL by making it possible to "compile" C code into closed-source proprietary bytecodes. See "Alchemy" for an example of Adobe being an immoral slimeball.

I'd like to add a slimeball exception to software I've written, preventing Adobe from benefitting, and yet I can't bring myself to be immoral just to combat immorality.

Comment Re:Portability.. (Score 1) 173

But you are advocating if I am reading you correctly 'to hell with other compilers use gcc4 it is the rocking best one out there'.

Then work on your reading comprehension. I said no such thing.

I said it isn't obvious that supporting other compilers was a good thing, and that it seemed obvious that actively supporting other compilers (i.e. "more work") had some serious costs that were being underepresented.

Re-read my post. Nowhere did I suggest anyone stop doing what they were doing.

Comment Re:Portability.. (Score 4, Insightful) 173

GCC is a great compiler, but relying on it excessively is a bad thing for the quality of kernel code ... it is simply healthy for the kernel to be compilable across more compilers.

Prove it.

The opposite (relying on GCC is a good thing for code quality) seems obvious to me. The intersection of GCC and ICC is smaller than GCC, so I would assume that targetting something big would afford greater flexibility in expression. As a result, the code would be cleaner, and easier to read.

Targetting only the intersection of ICC and GCC may result in compromises that confuse or complicate certain algorithms.

Some examples from the linked application include:

  • removing static from definitions
  • disabling a lot of branch prediction optimizations
  • statically linking closed-source code
  • tainting the kernel making debugging harder

I cannot fathom why anyone would think these things are "good" or "healthy", and hope you can defend this non-obvious and unsubstantiated claim.

(some of us still remember the gcc->pgcc->egcs->gcc debarcle).

When pgcc showed up, it caused lots of stability problems, and there were major distribution releases that made operating a stable Linux system very difficult: 2.96 sucked badly.

The fact that gcc2 still outperforms gcc4 in a wide variety of scenarios is evidence this wasn't good for technical reasons, and llvm may prove RMS's "political" hesitations right after all.

I'm not saying gcc4 isn't better overall, and I'm not saying we're not better for being here. I'm saying it's not as clear as you suggest.

Businesses

Belkin's President Apologizes For Faked Reviews 137

remove office writes "After I wrote about how Belkin's Amazon.com sales rep Mike Bayard had been paying for fake reviews of his company's products using Mechanical Turk, hundreds of readers across the Web expressed their outrage. As a result of the online outcry, Belkin's president Mark Reynoso has issued a statement apologizing and saying that 'this is an isolated incident' and that 'Belkin does not participate in, nor does it endorse, unethical practices like this.' Amazon moved swiftly to remove several reviews on Belkin products it believed were fraudulent. But now fresh evidence of astroturfing has surfaced, by the same Belkin executive."

Comment Re:So you think RSA is broken? (Score 1) 179

Oh, you actually want to read them? I thought you just wanted me to prove my cred.

I didn't doubt you went to school, or were completing a graduate level program on cryptography.

I doubted your competence, because you missed something I thought was obvious, and I am not a cryptographer.

That said, you mentioned you were working on identity systems, and I am interested in that. I want to say I do not seriously assume that your lack of experience with a particular kind of vulnerability assessment translates to a lack of competence in other things, and I apologize for my statement to the contrary on that subject.

I look forward to reading these papers after the holidays...

Comment Re:So you think RSA is broken? (Score 1) 179

Of course. It's just that this is 6-7 orders of magnitude easier than breaking RSA, even against a relatively hard target.

No. It's however hard breaking RSA is plus 6-7 orders of magnitude easier because you still need to break RSA.

Signings shouldn't help the attacker unless your hash is broken... it probably takes a worse break than the current ones against MD5 and SHA1, as well.

That's not true. doi:10.1016/S1007-0214(05)70121-8 for example on weak-key attacks against digital signature systems.

they [the banks] can upgrade much more easily than DNSSEC if RSA-1024 falls.

Sort-of. SSLv2 has been considered obsolete for a long time, but it took new PCI-compliance procedures to really shake it out of a lot of organizations I've worked with.

Upgrading is hard. Saying upgrading HTTPS's RSA-1024 is "easier" than upgrading DNSSEC is patently meaningless: We're not really talking about upgrading, we're talking about replacement.

There are still sites without MX records and still new FTP clients being made. I consider the proponents of DNSSEC and IPV6 similarly incompetent largely because they have spent so little time exploring how to replace our existing crap.

DNSCurve is primarily an exercise in supplanting the existing system; that's what the entire system is built on, *how do we get security*, not how do we build the most secure system, or the best system by any technical measure.

You probably want to avoid them anyway... I'm a grad student so I don't design very practical stuff

Implementations are uninteresting. Where are these identity schemes published?

Comment Re:So you think RSA is broken? (Score 1) 179

What the hell are you blathering on about?

As is common for crypto protocols, if the RSA key in HTTPS is broken, a man in the middle can mess with the protocol in real time.

No it can't. You still need a way to get the packets to the man in the middle, and a way to get the packets where they don't belong.

DNS, using UDP, offers no such protection.

Secondly, DNSSEC uses the RSA key for a long time, and clients can get lots of signings to launch offline attacks. This attack doesn't work on HTTPS, which uses RSA to only sign/encrypt a session key. It doesn't work on DNSCurve either.

All other things being equal, that answers mmell's question: Why is RSA safer for bank transactions than for DNSSEC?

How the hell can anyone be as fucking numb as you are to these two very simple things and still "be a cryptographer"?

I call shenanigans! If you're actually paid to design cryptosystems, let me know which ones so I can avoid them.

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