From: utzoo!decvax!harpo!duke!mcnc!unc!smb
Newsgroups: net.misc,net.math,net.wanted
Title: public-key cryptosystems
Article-I.D.: unc.3785
Posted: Wed Aug  4 12:32:33 1982
Received: Thu Aug  5 04:28:22 1982



Does anyone have an implementation of the Rivest-Shamir-Adleman public-key
encryption algorithm available?  Any responses would be appreciated.  (A
public-key cryptosystem is one where knowledge of an enciphering algorithm
E does not allow one to compute the deciphering algorithm D.  Thus, a
sender can encrypt some confidential text T with E(T); only the recipient
can compute E(D(T))==T.  The Rivest-Shamir-Adleman algorithm has the additional
interesting property that D(E(T))==T; this can be used to implement "digital
signatures", since only the sender can compute E(T), but anyone can apply
D to the result and see the original message.  This particular algorithm
was described in CACM 2/78, and also by Martin Gardener somewhat earlier
in Scientific American.  The public-key cryptosystem distributed with V7
UNIX is based on a different algorithm, one that cannot -- to my knowledge --
be used for digital signatures.)