Whitfield Diffie was born in Washington, DC, in 1944. He studied mathematics at MIT, receiving a BS in 1965.
On graduation, Diffie became an employee of the MITRE Corporation until 1969, when he joined the Stanford University AI lab to work with its director, John McCarthy, on proof of correctness of computer programs.
In the summer of 1972, Diffie's research interests changed to cryptography. In early 1973, he took a leave of absence to travel around the United States pursuing his new interest. He returned to Stanford with support from electrical engineering professor Martin Hellman, who was also pursuing research in cryptography.
Diffie and Hellman worked together throughout 1975 and were joined by Ralph Merkle in 1976. The results of their work appeared in Diffie and Hellman's paper, New Directions in Cryptography, in November 1976. The insights in this paper underpin secure transactions on the Internet, enabling e-commerce and a host of other interactions in which secure electronic communications are required.
In 1992, Diffie was awarded an honorary doctorate by the Swiss Federal Institute of Technology in Zurich, and in 2010, shared the IEEE Richard W. Hamming Medal with Ralph Merkle and Martin Hellman.