🚀 go-pugleaf

Imagine setting up a company to make cellular phones which use DES for
stream encryption, to avoid tapping by illegal radio receivers.  (There
might even be such a company...)

It would presumably encrypt traffic from the phone to the central office
where the call would then be decrypted and sent as a normal clear signal.

I would expect such a phone to be able to use a master DES key for
encrypting session keys -- and to use session keys for the call (all DES
keys being 360 bits -- 3x64 for IVs, 3x56 for keys -- triple encryption,
CBC mode).

However, if you happened to be calling someone else with phones from the
same company, it's reasonable to use the same session key for both phones
and skip the decryption step in the middle -- forgetting the session key
(probably originated in the home office) once the connection was
established.

In that case, the phone might light a little green light, indicating that
the call has been encrypted from handset to handset.


Given the FBI proposal last year asking for a back door for tapping and the
fact that it's still not law (hopefully never will be), I think it's time
for such a company to start selling phones -- just domestically, of course.

A decent public-key key-exchange mechanism could be added in later models
of the phones, as an extra feature.  The ones I suggest aren't that secure
from central-office tapping, but they at least would give the public a
taste of privacy.


Is anyone out there already working on this?


-- 
-- <<Disclaimer: All opinions expressed are my own, of course.>>
-- Carl Ellison						cme@sw.stratus.com
-- Stratus Computer Inc.	M3-2-BKW		TEL: (508)460-2783
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