| From: | Stainless Steel Rat <ratinox@***.NEU.EDU> |
|---|---|
| Subject: | Re: Easy Unbreakable Encryption! |
| Date: | Tue, 20 Jun 1995 11:57:16 -0400 |
<habelmon@********.CS.ADELAIDE.EDU.AU>
>>>>> writes:
Bob> The Idea: Quite SImply, alll that you would need to do is to take
Bob> the standard LinguaSoft programming framework, set in a random
Bob> element and produce specific language chips when you need them.
This is not an encryption scheme, it is a cypher.
This is a lot easier to break than you seem to think. Give me a large
enough sample of text to work from and I can break this cypher easilly,
because it is a cypher, not an encryption algorithm.
[...]
Bob> The only realistic way that the opposition can crack your code is
Bob> if they grab one of the chips from a dead teammate. SImple
Bob> solution, switch to backups.
Wrong. All cyphers are vulnerable to direct cryptanalysis, whereby the
cryptanalyst does "counts" of certain sequences. More common sequences
become certain common letters or words or phrases.
Here's a simple example: take the 26 letters of the alphabet and reverse
them so A becomes Z, Z becomes A, etc. Take the phrase "the quick brown
fox jumped over the lazy dog" and encypher it. Now count how many times
you see the letter "v" and how many times you see the letter "a" and
you
can find a correlation between those letters and the letters "e" and
"z"
respectively. And that's exactly what a skilled cryptanalist will do to
your code, using words instead of letters.
--
Rat <ratinox@***.neu.edu> |Caution: Happy Fun Ball may suddenly
http://www.ccs.neu.edu/home/ratinox/|accelerate to dangerous speeds.
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