🚀 go-pugleaf

In article <1992Dec10.184723.6236@octel.com> shaun@octel.com (Attack of the Dayglo Howler Monkeys) writes:

   Is there some way the public-key idea can be extended to handle a centralized
   distribution point?  That is, A sends a message to a redistribution point
   R, which forwards the message on to B, C, and D.  A performs encryption, and
   B, C, and D all decrypt the message and get authentication that it was
   from A as well.  R does nothing but redistribute, and contains no keys or
   encryption software.

   A would be responsible for collecting the public keys of B, C, and D.

Yes.  This is really simple, assuming A knows that B, C, and D are
going to be the only recipients.  All B has to do is encrypt the
message in some secret-key system (DES, IDEA, etc.), and then use
Public-Key encryption to encrypt the secret key in the Public Key of
*each* recipient on the list, and include that in the message, and
then send this whole thing to the mail-exploder, which will send the
message to everyone else.

If A, however, DOESN'T know the keys of B, C, or D, or if E gets added
to the list and A doesn't know this, the above method will fail.

-derek

--
         Derek Atkins -- MIT '93 -- Electrical Engineering
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