The Slow Death of the Code Breaker

On December 14, 1977 Ronald Rivest, Adi Shamir, and Leonard Adleman file for a patent for what came to be the RSA public-key encryption algorithm (named after the inventors).

Patent:

U.S. Patent 4,405,829 was awarded to the Massachusetts Institute of Technology on September 20, 1983 for its “Cryptographic communications system and method.” The three inventors, which the patent is named after, are Ronald Rivest, Adi Shamir, and Leonard Adleman. The patent expired on September 21, 2017, 17 years from the date it was issued.

The RSA cryptosystem, as described in the patent, is a public-key cryptosystem that offers both encryption and digital signatures. The cryptosystem is able to encrypt and create digital signatures by taking advantage of the fact that factoring is a “hard” mathematical problem. Factoring is actually one of three commonly used “hard problems” for cryptography; the other two are the discrete logarithm problem and elliptic curves.

The RSA cryptosystem has been incorporated into popular products such as Secure Socket Layer (SSL) and Secure Shell (SSH) as well as numerous other commercial products.