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Purdue Builds Quantum-Computing Semiconductor

Posted by timothy on from the odd-bits dept.

Bfaber writes: "According to EET, Purdue has created the first examples of quantum computing in a semiconductor. The story can be read here. Read the article for further links that include an audio interview."

5 of 102 comments (clear)

  1. Encryption... by Peridriga · · Score: 5, Insightful

    If you havn't you should read a book by Simon Singh called the "Code Book" it essentially is a history of cryptography from beginning to end (e.g. quantum cryptogrophy)....

    The effects of quantum cryptography is huge... Using a quantum computer would allow you to crack huge keys (everything from PGP, RSA, DES, TwoFISH, BlowFISH, etc.... anything you can think of) because of the essential basis of quantum physics...

    Simply in laymen terms you can check muliple cases of a key (i.e. check 111111 and 111112) at the same time... Not just 2 keys but, how about 2 billion keys per second... This makes any key no matter how long easily crackable...

    I promise you the NSA is up early this morning banging on doors at Purdue (hey the probably funded it anyway)....

    Now don't fear... Even though it makes any code breakable it also inheriently creates an unbreakable code using the same theories...

    So start writing all you stuff down and locking in a safe instead of encrypting it on your hard drive.... You data really isn't safe anymore...

    1. Re:Encryption... by rm-r · · Score: 2, Insightful

      Indeed, even when this becomes practical it sounds like it will be very expensive. It would also be much easy to legislate for and enforce a ban on civilian use of these devices. Afterall once the code for PGP got out anyone with a compiler could use it, even with a number of books on quantum physics and computing it would still require a massively expensive lab to build these devices.

      Looks like we've only got a couple of years of privacy left then...

      --

      J-aims
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    2. Re:Encryption... by lucius · · Score: 2, Insightful
      The effects of quantum cryptography is huge... Using a quantum computer would allow you to crack huge keys (everything from PGP, RSA, DES, TwoFISH, BlowFISH, etc.... anything you can think of) because of the essential basis of quantum physics...

      Acually, I don't think there are any published attacks for symmetric cyphers (most block and stream cyphers, if memory serves). The only published attack is Shor's famous factorisation algorithm. You're right that RSA is broken wrt quantum cryptography: it relies on the difficulty of factorisation (or synonymously, the difficulty of the discrete log).

      AFAIK, all public key systems rely on the discrete log, whereas few (none that I know of) "private key" systems do.

      This is not to say that there are no possible attacks on private key (symmetric) systems; there are just none published.

      Dave

    3. Re:Encryption... by color+of+static · · Score: 3, Insightful

      Only public key algorithms suffer from that level of security degradation due to QC. Factoring of a number on the order of 2^n, becomes about n operations on n qubits. Symmetric ciphers (such as blowfish, DES, Twofish, RC5, AES, etc...) only have a reduction in the keyspace needed to search. So if you have a 2^n key, you will have to search 2^(n/2) keys. While there may be a way of QC reducing this further, no current theory lends it's self to this.
      Of course what will it matter when there is a backdoor, and the only security is an Oracle agent smart card issued by the government?

  2. Obsoletes planned crypto laws by magi · · Score: 3, Insightful

    If they manage to get quantum computing working soon, and working well, we can forget these planned anti-crypto laws. Most crypto algorithms would go useless.

    With quantum computers, the only way to do crypto would be transferring huge XOR mask keys physically (or possibly with quantum encryption channels). Pretty hard.