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Comment TAOCP is a great reference, I still often use it (Score 1) 374

I like TAOCP, a lot; mainly, because the material is so coherent, precise, well justified, and understandable enough. I spent many weeks reading sections of TAOCP; especially volume 2, on Semi-numerical algorithms; my copy has several post-it marks on techniques useful in my field (applied cryptography): wide multiplication algorithms, modular arithmetic including exponentiation, statistical tests.
I also had significant uses of volume 1 (Fundamental Algorithm), which covers things such a tree, and hash tables; even purchasing the third edition, on top of the second.

That said,
- _reading_ TAOCP from start to end is not something to consider lightly; perhaps if one has a year to spend.
- I never caught on the use of MIX in some programs; I just skip this, and advise contemporary readers to do so, even if that's missing a part of the beauty.

Comment Information Sharing & Analysis Organization?! (Score 1) 29

The actual FCC noticel [FCC notice] has:
(6) Plans With Information Sharing and Analysis Organizations.
Plans to incorporate relevant outputs from Information Sharing and Analysis Organizations (ISAOs) as elements of the licensee's security architecture. Plans should include comment on machine-to-machine threat information sharing, and any use of anticipated standards for ISAO-based information sharing.

What's an ISAO? Here's what the DHS has to say. Short summary: Big Brother.

Comment Is what the FBI ask Apple feasible, or not ? (Score 2, Insightful) 400

There is something that does not add up in Apple's discourse at http://www.apple.com/customer-...

Specifically, the FBI wants us to make a new version of the iPhone operating system, circumventing several important security features, and install it on an iPhone recovered during the investigation. In the wrong hands, this software — which does not exist today — would have the potential to unlock any iPhone in someone’s physical possession.

The FBI may use different words to describe this tool, but make no mistake: Building a version of iOS that bypasses security in this way would undeniably create a backdoor.

I read what the FBI asks as: install a piece of code that allows the phone's content to be examined. I see no middle ground between

1) running such piece of code (probably: after getting it signed by Apple) is possible without the owner's passcode; the iPhone is in fact already backdoored, with Apple holding the key, the FBI wants Apple to exploit the vulnerability/open the backdoor, and Apple does not want to bow, because that's against their policy.

2) running a piece of code signed by Apple also requires he owner's passcode; then the solution pushed by the FBI just can't work.

If the facts where 2, Apple could just state this to the FBI, showing the source code as proof. The FBI would have no choice but take it as fact (perhaps they would ask a change in the future, but it would not help immediately for this iPhone). I conclude the true story is 1, and Apple slightly misrepresents things stating the FBI wants the creation of a backdoor, when there's already one, only well locked and never previously used for nefarious purposes.

Comment Police post plausible statement (Score 1) 415

Apparently the Rhode Island State Police posted a photo and plausible statement:

https://www.facebook.com/Rhode...

The post says the canine is "trained to detect electronic devices".

That does not look as bogus a claim as training specifically for storage media: the chemicals used in the soldering, cleaning, and IC packaging conceivably could have a detectable smell.

Comment The whole thing is unsubstantiated FUD (Score 1) 282

The whole thing is unsubstantiated FUD. I base my judgment on the slides at
https://media.blackhat.com/us-13/us-13-Stamos-The-Factoring-Dead.pdf

The whole argument boils down to:
a) there has recently been huge progress [*] in solving the Discrete Log Problem over fields of small characteristic;
b) progress in solving the DLP have historically implied progress in factorization, and vice versa;
c) factorization breaks RSA, and solving the DLP breaks DSA;
d) thus RSA and DSA are dead, move to ECDSA.

The fallacy of it is that in b) and c), the DLP is exclusively over fields of huge characteristics (thousands of bits), making the algorithms in a) powerless. The slides do not hint at the faintest research lead towards moving to huge characteristics. Best argument is that "renewed interest could result in further improvements".

One the positive side, the author is honest: "I’m not a mathematician, I just play one on stage".

    François Grieu

[*] See e.g. this recent paper and its references
Razvan Barbulescu, Pierrick Gaudry, Antoine Joux, Emmanuel Thomé: A quasi-polynomial algorithm for discrete logarithm in finite fields of small characteristic
http://hal.inria.fr/docs/00/83/54/46/PDF/quasi.pdf

Comment The report's author are pretty convincing (Score 1) 133

The original report says about the last vulnerability discussed (but not disclosed)

Indicators such as covert positioning, the use of special parameters, absence of log messages, facilitation of persistence, and apparent lack of legitimate purpose suggest that this vulnerability could be classified as a symmetric backdoor if malicious intent were to be established (which it has not).

I like the tone: they stop short of stating this is a deliberate backdoor of the worst kind, but give extremely convincing argument that it is one.

Comment Do not judge us from what we show! (Score 2) 85

The taken-down images, and the promotional video around 2:53
http://pages.ciphercloud.com/AnyAppfiveminutesdemo.html?aliId=1
make it clear that in these promotional materials, identical plaintext leads to identical ciphertext.

Ciphercould's DMCA takedown notice
http://meta.crypto.stackexchange.com/a/258/555
rebuts that as wrong ("Ciphercloud's product is not deterministic"), with a key point at the beginning of page 3:
"[detractor] implies that what was perceived from a public demo is Ciphercould's product offering".

Ciphercould's position is: you misjudged us from what we have shown, which is not the real thing.

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