RADIO: keys, ham, and subliminal channels

[elee9sf at Menudo.UH.EDU]

> The meaning must still be in clear but you are allowed to send a
> authenticating "signature" in code, as long as the signature 
> contains no information other than authentication itself that was 
> not also transmitted in clear.  That's why autopatch

Hmm... if authenticating signatures can be transmitted, then some
enterprising and patient cryptographers can also transmit messages,
encrypted if desired, back and forth using one of the "subliminal
channel" protocols!

A subliminal channel allows people to communicate by essentially
disguising their true message in the digital signature of the message
they transmit openly.  It would take several exchanges between the two
to transmit a real message, since I recall the subliminal channels
I've looked at allow the transfer of a few numbers at a time, but it
could be done!

/-----------------------------------\
| Karl L. Barrus                    |
| elee9sf at menudo.uh.edu             | <- preferred address
| barrus at tree.egr.uh.edu (NeXTMail) |
\-----------------------------------/