From: TO1SITTLER@APSICC.APS.EDU (Kragen Sittler)
Date: Sun, 18 Jul 93 00:03:37 PDT
To: cypherpunks@toad.com
Subject: stegano codes.
Message-ID: <930718005643.e25@APSICC.APS.EDU>
MIME-Version: 1.0
Content-Type: text/plain


In reference to a message by Mike Johnson:

I was thinking of steganography as being in two stages: first, you encrypt,
(possibly with the identity transformation) then, you embed your encrypted
message in your medium of transmission.  My previous message was describing
requirements for a strong encryption algorithm, quite apart from the actual
embedding.  I stand by my statements: the purpose of steganography is to make
it difficult or impossible for an interloper to determine that enciphered data
are being transferred.  Thus, embedding a magic number in the file defeats the
purpose completely.
(As opposed to "slightly reducing security.")

I accept your correction regarding availability of software.

I think that designing a program to embed this apparently random bitstream in
an innocent-looking file is a different and much harder problem.

It is probable that I have misunderstood some part of your message, and I
apologize if this is the case.

Kragen
(Bug my sysman for a newsreader that allows quoting with >'s-his username is jim.)