🚀 go-pugleaf

In article <9112@duke.duke.UUCP> srt@duke.UUCP (Stephen R. Tate) writes:
>In article <1338@navajo.STANFORD.EDU>, les@navajo.STANFORD.EDU (Lester Earnest) writes:
>> The easiest way to compromise an exclusive-or cryptographic scheme with
>> courier-distributed key is to bribe the courier and make a copy.  
>
>Now here's an interesting point.  The exact same amount of information has to
>be transmitted as "key" information as will be transmitted as data.  Now since
>the data is transmitted over an insecure channel, then the key data is the
>valuable information.  So why not just use the secure courier for sending the
>actual data?  

The key channel must be secure but may be very slow (e.g. a sealed packet in
a hand-carried diplomatic bag once a month) but the messages are timely over
an insecure channel (e.g. radio transmissions).    This is the procedure
used by foreign embassies, for example.

Also, in information theory "value" does not necessarily equal "bit count"!








[sorry about the blank lines but first time inews rejected it because
on grounds that I had not added enough lines.   What a dumb 'feature'.]

-- 
Regards,
        David Wright          STL, London Road, Harlow, Essex  CM17 9NA, U.K.
dww@stl.stc.co.uk <or> ...seismo!mcvax!ukc!stl!dww <or> PSI%234237100122::DWW