At 06:07 PM 10/4/00 -0500, Jim Choate wrote:
>On Wed, 4 Oct 2000, Ray Dillinger wrote:
>> On Wed, 4 Oct 2000, Tom Vogt wrote:
>> > how do you find out whether or not a message is encrypted?
>>
>> Plaintext looks like plaintext.
>
> Yeah, if the only thing you right is simple English.
> Most of the planet doesn't speak English and their plaintext
> doesn't necessarily look like plaintext. This is a xenophobic view.
8-bit-alphabet plaintext looks like plaintext.
It's easier to recognize popular languages - short bunches of
letters separated by spaces. Less popular languages that use
8-bit alphabets still have easily detected statistics that
are much different from uniformly-distributed cyphertext.
Languages with N-byte characters are much harder -
you have to decide whether to look at Unicode,
(2-byte's bad enough; variable-byte is worse),
otherwise you'll get totally hosed on your chi-squares.
Things that start with popular magic numbers like gif89
also look like plaintext (though they may in fact be stego.)
Thanks!
Bill
Bill Stewart, [EMAIL PROTECTED]
PGP Fingerprint D454 E202 CBC8 40BF 3C85 B884 0ABE 4639
