Quantum cryptography

[darkes]

Interesting reports in the news recently about using optical fibres to produce a system that is 'uncrackable'. A reaonable summary can be found here - quantum , and no doubt elsewhere as well.
Probably be a few years before it is commercially viable, but from a scientific point of view it would seem to have a lot of merit. In many ways a bit like Heisenburg's uncertainy principle - which basically means that, for a single particle, the better you know its position the worse you know its velocity - or vice-versa.

[dfgt5]

what if you forgot the password to your key?

[darkes]

Must remember to take up a course in typing soon Edited my post so that the link is correct. Like all encryption systems it won't work if you don't know what your key is - but in many ways that is the point - without the key you can't read it. At a software level this could use something like PGP, or something more sophisticated.

[VictorKaum]

Are you ppl here dealing with the idea of quantum compus?

Well some1 said it could be uncrackable?

Why not use quantum computers to crack the passwd key generated by a quantum compu? Even if it was so complicated as a double helix proteïn string it probably can be cracked by some very fast machine. In the process of time every key or hash can be found and translated into plain text, it's just a matter of time. Perhaps a vvvvvveeeeerrrrrrryyyyyyy long time but in theory it's possible. So uncrackable? No way

[MrLinus]

Quantum cryptography is not unbreakable. Nothing is. It is just that we do not have the feasible technology to do it yet. Simon Singh's The Code Book has an excellent chapter on Quantum Cyrptography that I found I actually had a clue from. (If you are interested in the history of cryptography, this is a book I'd highly recommend).

Scientific American has also has a small article on it:

http://www.sciam.com/news/122200/2.html

Now, one of the biggest issues is the abilities of our present OSes and hardware to be able to handle this stuff at an efficient and cost-effective manner. I'd humbly suggest that not even by military standards do they have the bucks to do it. It will be a few years before this is viable and proven to work in an environment of work or something like that.

I absolutely love this stuff. Now ask me how good I am at math? =D

[RogueSpy]

I absolutely love this stuff. Now ask me how good I am at math? =D

How good are you at math? ; )

[souleman]

I remember reading something that said DES was uncrackable. Then computers got faster. Then that phone encryption by the NSA was supposed to be uncrakable(can't remember the name), but they finally released the source code. That didn't last long. So now something else is uncrackable, but that is only till someone cracks it.

Simon Singh's The Code Book is a great book like MsMittens said. I am reading it right now. There is also a book called CODE, if you are interested in how computers and encryption work and are related. Can't remember who wrote it, but it was by Microsoft Press, so it wasn't the best book.

MsMittens, I agree with rogue, how good are you at math?

[darkes]

I think the point that they were trying to make was that this makes physical interception of the message all but impossible. Well it is impossible, unless someone is keeping quiet about recent developments in quantum theory. If you try to pysically intercept the message then you alter the information that the other end receives - which is not true of any other method used today. All this is completely irrelevant if you send the data via other computers (e.g. ISPs), as the ISP can take a copy of the message.

And as has been pointed out, the most important thing is how you do the encryption, and any other precautions you take. Really depends on how you would implement this type of technology.

[proactive]

Current cryptograhy tecniques are 'impossible' to crack, it's just a question of using a long enough key.

I heard that to crack a 4000-something length key for the RSA-encrytpion algorithm, you would need all excisting computer power in the world. And it would take the rest of the universe' liftetime to do so. And even then, you couldn't be sure of cracking it, but maybe...

But of course there is only a question of computer power, if the computers are powerful enough, it's no big deal really.... In 1997 a 128 bit RSA was cracked by a program which united lots of pc's around the world. Sort of like the SETI screen-saver. And that too, was supposed to be 'unbreakable'.

[morfius]

I would agree with most of the people in this post. It isn't a question: is it unbreakable? but it's really a question of: how long will it take to crack?
As history tells us that nothing is unbreakable, when things get tougher, other things get faster. And vice versa. We're all in an race through a technological black hole. Looks like it'll never end... or will it?