Martin Edward Hellman (born October 2, 1945) is a cryptologist, famous for his invention of public key cryptography in cooperation with Whitfield Diffie and Ralph Merkle.
The method of public key distribution he helped create would later be called the Diffie-Hellman key exchange
Currently is a Professor Emeritus of Electrical Engineering at Stanford University
http://en.wikipedia.org/wiki/Martin_Hellman
http://www-ee.stanford.edu/~hellman/
http://en.wikipedia.org/wiki/Diffie-Hellman_key_exchange