2013-08-14 Phys.org: Encryption is less secure than we thought

[BitGo]

http://phys.org/news/2013-08-encryption-thought.html

"In information theory, the concept of information is intimately entwined with that of entropy. Two digital files might contain the same amount of information, but if one is shorter, it has more entropy."

"The problem, Médard explains, is that information-theoretic analyses of secure systems have generally used the wrong notion of entropy. They relied on so-called Shannon entropy"

"But in cryptography, the real concern isn't with the average case but with the worst case. A codebreaker needs only one reliable correlation between the encrypted and unencrypted versions of a file in order to begin to deduce further correlations."

""It's still exponentially hard, but it's exponentially easier than we thought," Duffy says."

"Bloch doubts that the failure of the uniformity assumption means that cryptographic systems in wide use today are fundamentally insecure."

[TraderTimm]

What bothers me about this article is how encryption reversibility is "exponentially hard", but in the same sentence it is "exponentially easier"?

How about some actual figures? I'd like to know if I'm reading about something that will be on our doorsteps in short order, or is still a vague and distant concern.

[Carlton Banks]

Stop the press: Progress in Mathematical Theory Still Possible!


 

[cbeast]

 "by assuming coded words are drawn from a
source’s typical set and so, for all intents and purposes, uniformly
distributed within it. "

meh.

[Le Happy Merchant]

"by assuming coded words are drawn from a source’s typical set and so, for all intents and purposes, uniformly distributed within it. "

meh.

Seconded, this assumption doesn't hold for Bitcoin. Additionally, Bitcoin isn't mentioned in the article. This is peripherally on topic at best.

[BitGo]

"by assuming coded words are drawn from a source’s typical set and so, for all intents and purposes, uniformly distributed within it. "

meh.

Seconded, this assumption doesn't hold for Bitcoin. Additionally, Bitcoin isn't mentioned in the article. This is peripherally on topic at best.

This article is pretty relevant because bitcoin is based on an open-source cryptographic protocol, and this article is about cryptography. I think we should be aware of any potential issues with cryptography in order to keep bitcoin safe.

[cbeast]

"by assuming coded words are drawn from a source’s typical set and so, for all intents and purposes, uniformly distributed within it. "

meh.

Seconded, this assumption doesn't hold for Bitcoin. Additionally, Bitcoin isn't mentioned in the article. This is peripherally on topic at best.

This article is pretty relevant because bitcoin is based on an open-source cryptographic protocol, and this article is about cryptography. I think we should be aware of any potential issues with cryptography in order to keep bitcoin safe.

The "dictionary" type attack they are discussing might only be relevant for brain wallets, but not wallet generated addresses.