Discussion in 'Int Corps' started by Nehustan, Dec 8, 2005.

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  1. Nehustan

    Nehustan On ROPs

    Hi there guys, I wondered if there were any 'math' types on the forum, that know a little about encryption software and the keys they use. Does the 'key' effect the algorithm i.e. is it encrypted using a 'fractal' so as to speak, or does the key just act as a password?

  2. Nehustan

    Nehustan On ROPs

    Thanks TA_Sig, very rapid repsonse. I have just got hold of an app, and really it would be as simple as emailing the producer I guess, already had a look at wiki.

    I just wondered to what degree files become encrypted, whether it fortifies the perimeter, or totally jumbles the content, I guess it must be the latter otherwise the file would be 'protected' rather than encrypted.
  3. I'm mathematcian (though not a specialist in encryption). I refer you to the article


  4. This is only one form of encryption known as asymmetric or public-key encryption. RSA requires 2 keys generated from 2 large primes as described above but due to the size of the numbers involved it is too slow for simple file encryption. Symmetric algorithms use a single key which is combined with sequential blocks of data from the file in any number of ways (depending on the algorithm) in order to mask the content.
  5. Nehustan

    Nehustan On ROPs

    I actually chatted with someone in our IT dept today about algorithms and the way they reorganise/encrypt data, very interesting.

    Thanks for you post tho' wowbagger. He actually directed me to the 'best' piece of software for the job in his opinion (PGP), which encrypts using RSA with up to 4096-bit keys With public and private keys, and DSA using 1024-bit key only. This is very cool stuff, which I know a little more about than yesterday.
  6. PGP is a hybrid: It uses a symmetric key to encrypt the data, and PKE (Public Key Encryption) to encrypt the symmetric key. symmetric encryption algs tend to be faster than PKE by a ratio ~ 1000:1 so you get the speed from one and the convenience of PKE which removes key distro problems. It's a simple principle and you can insert your favorite PKE alg and symmetic alg and cook your own.

    There is a far superior algorithm which has been developed recently, namely ROT13 :


    also worth a look.
  7. Nehustan

    Nehustan On ROPs

    Funny sod....I actually used ROT13 some years ago in combination with the Runic futhark, like it says not really an encryption system as much as as a device to avoid prying eyes :lol:

    [align=center]AHBH AChD[/align]
  8. Being a geek 1st class with oak leaf cluster, I recommend "the book they tried to ban" which is the standard reference on this subject - "Applied Cryptography" by Bruce Schneier.

    Its on my bookshelf, so help me
  9. funny, i got prescribed ROT13 last time i got a dose...
  10. Ditto! :oops:
  11. Nehustan

    Nehustan On ROPs

    well I have a couple of tank tops...maybe a copy is all I need to complete my geek chic :wink:

    (geek chic complete - ordered from amazon!!! Now if I don't have women hanging off me at parties I want my money back!!!! Guess I could always try the friendly bacteria line...it works on the TV 8O )
  12. Yes, but did you know they are," Provably" crackable, given time and computational resources. Why do you think the key length gets longer and longer?

    128-bit, 4096-bit, 1024-bit does not equal more secure. Just takes longer to crack with a given set of resources. Here though, Moors law and the invention of technologies like, distributed computing outstrip the use of current encryption algorithms.

    This is the fundamental problem with all, currently, used computer encryption algorithms. (At least those we mortals know about)
  13. honestly, and you dark siders wonder why we take the p*ss... ;)
  14. If you want a non-geek friendly read then try Simon Sharma's "The Code Book" it details loads of stuff from how the Egyptian hyroglyphs were decyphered, how the Poles cracked the early Enigma codes and how a Brit invented computer encryption but couldn't tell anyone (or patent it) at the time...a good read and not (too) technical.