On Fri, 8 Dec 1995, Mr.Sunay Gandhi wrote:
On Wed, 6 Dec 1995, John Pilley wrote:
> Ladies and Gentlemen:
> The asynchronous scheme of encryption/decryption invented by Rivest, Shamir
> & Adleman involves the use of multiplicative inverses, a modulus and a
> public and secret key chosen/derived from the primes whose product makes up
> the modulus.
> Would one of you good people point me towards a proof(?), derivation(?),
> explanation(?) showing (Mathematically) how it works?
> John Pilley at InfoSystems Inc.
> (509) 328-9108
The College Professor for my networking class had a simple laymens
explanation for how RSA public/private key functions work and are used.
Once you have your two keys, you have essentially two functions f(x) and g(x)
that are inverse functions. This gives the property that f(g(x))=x and
g(f(x))=x. The properties of RSA are such, that if you know the algorithm
f(x), it does not tell you what the algorithm of g(x) is. Lets say, two
persons want to communicate with non-repudiation (digital signiture).
Each person has their pair of keys (F(x), G(x) and f(x), g(x) ) To
prove the source and intended destination, the keys ( F(x), and f(x) )
are published in a secure fashion as 'Public' keys. If the letter was
being sent from lower case to upper case, the encryption would be done in
the following fashion
F(g(x)) = y -----> f(G(y))=x
Since f(x) is used to decode, It must have been created by the owner of
the private key g(x). And Since G(x) decodes it, it must have been
intended to be sent to the owner of G(x) private key, since F(x) must
have been used to code the message
Hope this has been useful
Personal opinions provided by
aka leonard @
GEMINI COMPUTERS INC.
Web Page www.geminisecure.com