>Message: 1 >Date: Wed, 14 Jan 2009 11:47:58 -0500 >From: "Robert J. Hansen" <r...@sixdemonbag.org> >Subject: Re: Dan Brown - Digital Fortress book
>The TRANSLATR machine does not work and cannot work, not under the >laws of physics as we know them to be. ok, granted, as well as the inaccurate crypto of the 'uncrackable' cipher, but it does raise a fascinating question: "assuming a brute force attack is feasible in real time, how could one design a cipher that is invulnerable to brute force attack (other than an OTP )?" as a general possibility: (1) [as explained in the Digital Fortress book] what if the decryption program didn't know when it had successfully decrypted ... (a) change the ciphertext, and let the brute force machine merrily try to crack the wrong ciphertext ... (re-encrypt the ciphertext with another random session key, then if the brute force attack tries all possible ciphertexts to find which one is the right one, it sort-of becomes similar to attacking an OTP, in that the brute force decryption would yield several plaintexts of contradictory information in practice, though, the attacking program could just brute force the keyspace of the re- encrypted ciphertext, until it would get a ciphertext that would decrypt to a real plaintext, so, unless there is a way to re-encrypt the ciphertext in a way that it could produce multiple different plaintexts when using different session keys, it wouldn't work anyway, for me, the book presented interesting crypto concepts that would be fascinating if explored ... vedaal any ads or links below this message are added by hushmail without my endorsement or awareness of the nature of the link -- Chart your path to success with a smart new business plan. Click here! http://tagline.hushmail.com/fc/PnY6qxuGjH0bAoYNLlgSwxAbAOPbFAIUKUFsAtjCQvRzonDO04TM7/ _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users