Public key encryption method
used in pretty good privacy (PGP)
electronic commerce (SEC), and a part of ANSI, ISO and other international encryption standards. RSA is based on the simple arithmetical fact
that it is relatively easy to multiply two large prime numbers but extremely difficult to work
backward from the product
to find those prime numbers. This technique
allows the unique public encryption key (the product of prime numbers) to be disclosed to any one but which can be decoded only with the secret private key
(the prime numbers). RSA key size falls between 768 and 2,048 bits; thus, there can be 22048 possible combinations a truly astronomical number that can resist practically any 'brute force' code-cracking attempt.
Released in 1977, RSA is named after its inventors: Ron Rivest, Adi Shamir, and Leonard Adleman.