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1978 Cryptosystem Resists Quantum Attack
KentuckyFC writes "In 1978, the CalTech mathematician Robert McEliece developed a cryptosystem based on the (then) new idea of using asymmetric mathematical functions to create different keys for encrypting and decrypting information. The security of these systems relies on mathematical steps that are easy to make in one direction but hard to do in the other. Today, popular encryption systems such as the RSA algorithm use exactly this idea. But in 1994, the mathematician Peter Shor dreamt up a quantum algorithm that could factorise much faster than any classical counterpart and so can break these codes. As soon as the first decent-sized quantum computer is switched on, these codes will become breakable. Since then, cryptographers have been hunting for encryption systems that will be safe in the post quantum world. Now a group of mathematicians have shown that the McEliece encryption system is safe against attack by Shor's algorithm and all other known quantum algorithms. That's because it does not depend on factorisation but gets its security from another asymmetric conundrum known as the hidden subgroup problem which they show is immune to all known quantum attacks."
> If it can be engineered, it can be reverse-engineered.
How does that apply to this article, in any way?
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It is worth noting that solving hidden subgroup problem is a subfield of quantum computing that has been active for a while. Although we can't figure out how to solve it in general, we can solve specific instances of it; for example, I think that factorizing is one such instance.
Thus, I suspect that we will eventually figure out a way to break this encryption. Even if we do, though, these mathematicians still get credit for giving us a new instance of the hidden subgroup problem to try and solve, which may give us additional insight into the extent to which the general problem can be solved by a quantum computer.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Would ElGamal also be immune since it's based on Discrete Logarithms?
I wonder if "THEY" already have one of these quantum computers and are keeping a lid on it so they can snoop on the PGP of our enemies. Would it be possible to develop one of these in secrecy?
If it can be engineered, it can be reverse-engineered.
That only works for "security through obscurity" type of problems. A good encryption should not be "solvable" - it must be brute forced. The question is how expensive the brute force method is in processing power and time.
It doesn't apply to this article. The way that one typically breaks a cryptosystem is not by reverse engineering (which is not even meaningful here, given that the algorithm is already completely open), but by finding a clever new way to solve the mathematics underlying the system using less information than the designers of the system had thought was needed.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
This is not a brute-force attack. The article refers to a method of deriving the private key from the public key (which is available for anyone to download).
Send a bunch of encrypted e-mails containing questionable content and see if anyone comes knocking at your door. And be sure to not send any questionable content unencrypted, or to give any other reasons for them to show up.
You can lead a horse to water, but you can't make it dissolve.
Feel secure again. Only a variant was broken.
How can I believe you when you tell me what I don't want to hear?
Symmetric algorithms are at least in their second generation (DES/Lucifer now AES) of production use, with decades of study and close analysis by a lot of good minds.
Asymmetric algorithms are still essentially the first generation. Take RSA. It has been out for so long that its patent has expired more than 15 years ago. Even elliptic curve cryptography has been out at least 20 years, because the NeXT had it in NeXTStep 3.0 (and ended up getting pulled out of the OS due to ITAR).
Even cryptographic hashes have been through a number of iterations. We had MD4, then MD5, then SHA-1, then SHA-256, now are looking for something to replace SHA, similar to how Rijndael replaced 3DES and DES.
Maybe it is time to have a contest to have a standard asymmetric algorithm to replace RSA, DSS, and ElGamal? Something fundamentally designed to resist quantum computer attack as well as other threats.
Thus, I suspect that we will eventually figure out a way to break this encryption. Even if we do, though, these mathematicians still get credit for giving us a new instance of the hidden subgroup problem to try and solve, which may give us additional insight into the extent to which the general problem can be solved by a quantum computer.
From TFA:
However, it's worth pointing out that while the new work guanratees safety against all known quantum attacks, it does nothing of the sort for future quantum attacks. It's perfectly possible that somebody will develop a quantum algorithm that will tear it apart as easily as Shor's can with the RSA algorithm. "Our results do not rule out other quantum (or classical) attacks," says Dinh and co.
"I don't care about the Constitution!" --Bill O'Reilly, November 17, 2009
Seriously, Slashdot gets it wrong EVERY TIME. Next time, would it kill the editor to go to http://www.caltech.edu/ and, you know, read any of the words on the page?
Actually, with really hard-core crypto systems there are three traditional ways to break them: 1) rubber hose; 2) dumpster diving; or 3) box of chocolates/bouquet of roses.
Actually, with really hard-core crypto systems there are three traditional ways to break them: 1) rubber hose; 2) dumpster diving; or 3) box of chocolates/bouquet of roses.
What no wad of Cash xor hookers & blow?
A sociological observation is that Shor was an undergrad at Caltech when McEliece was a professor there formulating the cryptosystem that would resist the quantum algorithm that Shor would develop years later. I wonder if knew each other.
The only encryption method I've heard about that has not been found to be breakable is the one time pad. This method has the problem of exchanging the pads beforehand.
All of the major encryption machines used during WWII appear to have been broken. The new encryption methods are currently much harder to break, but the spooks are likely to discover some innovative method to break such algorithms.
Current methods using large prime numbers sounds like they are soon (next few decades) to be broken. If we got into a war where breaking these methods became important, I'm sure that quantum computers would soon become available, if they aren't already. Even if quantum algorithms aren't available, someone might come up with a way to calculate prime factors using a bacteria colony through DNA molecules. A method may cost a million dollars per factor found, but sometimes that is small change for the information gained.
I'm sure that there are groups looking for the next level of encryption. Something that isn't compatible with quantum methods, or requires it to reverse the encrypted data. Making it take longer and be more expensive to break is the goal of encryption.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Feel secure again. Only a variant was broken.
The date of your document July 2008 precedes the successful decryption in October 2008.
When the foot seeks the place of the head, the line is crossed. Know your place. Keep your place. Be a shoe.
W8, why both of them wouldn't work?
One that hath name thou can not otter
That falls under the generalization of (3).
(1) Threat/intimidation/violence
(2) Exploit a careless mistake
(3) Bribery/persuasion
I suppose (1) and (3) even could blur together into "influence" (negative and positive).
...the future crusty old bastards are already drinking the Kool-Aid.
WTF... OK... I can deal with slashdot being overrun by morns who know little but act big, but now we have to put up with text-ese ?
His UID is lower than yours so shouldn't it be "I can deal with that slashdot was overrun by morns who knew little when I signed up. (eol)"
Maybe he did, maybe he didn't.
Infuriate left and right
There is an old paper, written by DJB, which gives a quick introduction to some (this and) other quantum computer resistant encryption methods: Introduction to post-quantum cryptography
It's worth noting that social engineering is quite often the cheapest method. I was at a conference back in 1999, where a Navy guy pointed out that in 'red team' testing, they'd found that the typical Systems Administrator would roll over for an average of $7000. No, I don't know how the details of how they conducted the test.
One could argue (or hope) that _most_ SysAdmins these days are more cognizant of the risks, so probably not as casual as they used to be.
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How do you brute force (or solve) a one-time pad, where the pad was created from random atmospheric noise or any other truly random source?
[...]
The only downside (and it's really not much of a downside) of OTP technique is that you need the pads before you need the message. However, I actually can't think of a situation where that would seriously inconvenience modern users of the technique.
Oh, and how do you unbreakably update OTPs in the field? Easy: You encrypt them with the last/reserved OTP the other end has. Cyclic encryption of truly random numbers? Incomprehensible. It's just another 100% opaque data stream. Done deal.
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No, it doesn't brute force every possible combination. You can perform an operation on a superposition of all possible k-bit strings, but you can't actually get all of the 2^k outcomes of that operation. If you measure the result, you'll get one of the 2^k outcomes at random.
Basically you start from that superposition of k-bit strings, then you apply some operations to that state so that all of the the correct answers are in phase with each other and constructively interfere. Effectively, you can only apply this kind of speed-up if you can exploit the numerical properties of the problem to ensure that this happens.
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