Encryption with Python

[Peter Hansen]

Dennis Lee Bieber wrote:

> On Fri, 25 Jun 2004 08:45:43 -0400, Peter Hansen <peter at engcorp.com>
> declaimed the following in comp.lang.python:
>>Kamilche *did* state clearly that it was "not secure, but it should
>>be enough to ward off casual hacking".
> 
> 	About to the level of the old "CryptoGrams" puzzles some
> newspapers run (though they usually give you one starting substitution
> -- but in a long missive, that type of hint may not be needed).
> 
> 	It would be a slow implementation in Python, but one
> "improvement" I'd consider (since it looks like there are already
> multiple tables): Using just a..z0..9 (ignoring case and punctuation
> characters) would be to create 36 substitution tables, then use the
> output of one character substitution as the index to the table for the
> next character's translation.
> 
> 	This would avoid the "bookkeeper" type input from giving hints
> in the output. The reverse (decryption) gets a tad more difficult.

But why would anyone want to improve the security of this approach?
If one wants casual obscurification(tm), it does just fine as-is.
If one wants real security, one would be insane to use anything
less than Blowfish, 3DES, AES and their ilk...

-Peter