Re: Questionable logic ?

Chris Henesy (lurker@cc.gatech.edu)
Mon, 12 May 1997 01:05:56 -0400


At 11:14 PM 5/11/97 -0500, Michael R. McClelland wrote:
>I don't study crypto so just humor me OK? If two people plan to communicate
>using encrypted messages then they both have to know which key to use and
>how to use it.

The solution to this problem comes in the form of 'Public Key ' encryption
like is found in PGP. While I am not an expert on the subject I can offer
a brief explanation. You have two keys, each based on the other
mathmatically. One is public and you give it to anyone who might want to
send you somthing in an encrypted form. The other is private and you keep
it on a secured system where no one can get to it. Anything that is
encrypted with the public key, can only be decrypted with the private key.
Now you may wonder why you can't determine the private key FROM the public
key, and all I can say is that it's based on some fancy mathamatics and the
fact that it is VERY diffacult to factor the product of very large prime
numbers. I'm sure someone else can give you a more complete description of
that process, but thats the basic idea.

-Chris

Can't keep my eyes from the circling sky. | Systems Analyst
Tongue tied and twisted, | Distributed Computer Ops.
Just an earth bound misfit, Am I. | Georgia-Pacific Corporation
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