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H_TeXMeX_H 05-23-2013 08:07 AM

"Uncrackable Cryptography"
 
http://it.slashdot.org/story/13/05/2...e-cryptography

Quote:

"One-time pads are the holy grail of cryptography — they are impossible to crack, even in principle. However, the ability to copy electronic code makes one-time pads vulnerable to hackers. Now engineers at the California Institute of Technology in Pasadena, have found a way round this to create a system of cryptography that is invulnerable to electronic attack. Their solution is based on a special kind of one-time pad that generates a random key through the complexity of its physical structure, namely shining a light through a diffusive glass plate."
So, what do you say is in "uncrackable" ?

I say how crackable it is depends a lot on your RNG.

Quote:

The security of this process depends on two factors. The first is the randomness of the digits that make up the one-time pad. If this key is truly random, it offers nothing the eavesdropper can use to break the code. Although there are some potential pitfalls, random digits are reasonably straightforward to generate these days.
http://www.technologyreview.com/view...ng-impossible/

Are they really ? I'm quite sure that true random numbers or ever cryptographically secure random numbers are very difficult to come by and difficult to verify these days. The diffusing glass approach in this article is not convincing either.

Also see:
https://en.wikipedia.org/wiki/One-time_pad#Problems

Quote:

The theoretical perfect security of the one-time-pad applies only in a theoretically perfect setting; no real-world implementation of any cryptosystem can provide perfect security because practical considerations introduce potential vulnerabilities. These practical considerations of security and convenience have meant that the one-time-pad is, in practice, little-used. Implementation difficulties have led to one-time pad systems being broken, and are so serious that they have prevented the one-time pad from being adopted as a widespread tool in information security.

One-time pads solve few current practical problems in cryptography. High quality ciphers are widely available and their security is not considered a major worry at present. Such ciphers are almost always easier to employ than one-time pads; the amount of key material which must be properly generated and securely distributed is far smaller, and public key cryptography overcomes this problem.[16]

vmccord 05-23-2013 09:20 AM

Way easier to crack/hack the human elements.

John VV 05-23-2013 02:53 PM

yep there will always be a " PEBCK /"PEBCAK"

Habitual 05-23-2013 05:16 PM

Years ago, not having a password was a show-stopper, Now it is merely an inconvenience.
and tomorrow some "guy" will show up with a cryptographic version of the Dresden Codex.

We live in interesting times.

Martin Bishop out.

dugan 05-23-2013 05:38 PM

Quote:

Originally Posted by Habitual (Post 4957594)
And tomorrow some "guy" will show up with a cryptographic version of the Dresden Codex.

We have those. They're called rainbow tables.

273 05-23-2013 06:28 PM

Isn't the scheme described in the original paper just Diffie–Hellman–Merkle with novel key generation?

jefro 05-23-2013 08:56 PM

I don't believe in uncrackable encryption.

ntubski 05-24-2013 11:58 AM

Quote:

Originally Posted by 273 (Post 4957628)
Isn't the scheme described in the original paper just Diffie–Hellman–Merkle with novel key generation?

It looks like the scheme they describe requires meeting to securely establish a shared secret before hand; unlike Diffie–Hellman–Merkle.

273 05-24-2013 12:07 PM

Quote:

Originally Posted by ntubski (Post 4958274)
It looks like the scheme they describe requires meeting to securely establish a shared secret before hand; unlike Diffie–Hellman–Merkle.

Ah, true. So more like a physical version.

patrick295767 05-27-2013 11:01 AM

this reminds me the movie when one hacker try to hack a system (for $). I cannot remember me the name of the movie, maybe swordfish?

273 05-27-2013 11:07 AM

:D Swordfish where he writes a virus in AutoCAD and comments his intrusion code while he's trying to breech a system as quickly as possible.

trevoratxtal 05-27-2013 11:25 AM

What man can invent another man can reverse engineer!
 
I support jefro.
Quote:

Originally Posted by jefro (Post 4957686)
I don't believe in uncrackable encryption.

I will stick my neck out and state Nothing is uncrackable, given the time and resource's.
Prime Minister Churchill was of the same mind, thankfully or else a different regime would rule the Western world.
Trev

273 05-27-2013 11:30 AM

Quote:

Originally Posted by trevoratxtal (Post 4959938)
I support jefro.

I will stick my neck out and state Nothing is uncrackable, given the time and recourse's.
Prime Minister Churchill was of the same mind, thankfully or else a different regime would rule the Western world.
Trev

Mathematics proves you wrong:
http://en.wikipedia.org/wiki/Quantum_key_distribution
http://en.wikipedia.org/wiki/One_time_pad
Of course, we tend to trade security for convenience but there's no need to say one has to.

jefro 05-27-2013 07:12 PM

"It should be noted that the researchers categorically state that while McEliece's algorithm cannot be cracked by current quantum cryptography attacks, they are not taking any bets on whether it can withstand attacks dreamt up in the future."

http://www.theinquirer.net/inquirer/...on-uncrackable


The security of a scheme is only dependent on all parts being secret. Any fraction of the key or scheme or any part of the data may result in the entire data being decoded. You know the big governments have super computers working on all this right now. Remember when pgp was in trouble for being uncrackable until the US cracked it.

273 05-27-2013 07:29 PM

Quote:

Originally Posted by jefro (Post 4960167)
The security of a scheme is only dependent on all parts being secret. Any fraction of the key or scheme or any part of the data may result in the entire data being decoded. You know the big governments have super computers working on all this right now. Remember when pgp was in trouble for being uncrackable until the US cracked it.

That is true but with a one time pad you can only know the key to the plaintext that you have if you have both plaintext and cyphertext -- you cannot know or infer the key to any other cyphertext. There is no mathematical attack against it. It is 100% uncrackable, always has been and always will be.
So, then you are left with the very difficult job of key distribution. This is where the plan usually falls down in the real world when people reuse keys or lose codebooks. This is what things like quantum key exchange are there for. Theoretically speaking quantum key exchange is unbreakable -- now it will take many decades to make that theory practice.

As to the original scheme -- I agree that it sounds like it will be broken at some point in the future but I think it sounds like it may work in some situations for long enough to be worth looking at.


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