Diffie is Visiting Professor at Royal-Holloway College of the University of London and Visiting Scholar in the Center for International Security and Cooperation at Stanford University.
He began his career in security as the inventor of the concept of public key cryptography, which underlies the security of internet commerce. He has made fundamental contributions to many aspects of secure communications and was instrumental in the rise of a public cryptographic research community.
In the 1990s he turned his attention to public policy and played a key role in opposing government key-escrow proposals and restrictive regulations on the export of products incorporating cryptography. Diffie recently retired from his position as Chief Security Officer at Sun Microsystems and is now studying the impact of web services and grid computing on security and intelligence.
Prior to assuming his position at Sun, Diffie was Manager of Secure Systems research at Northern Telecom throughout the 1980s.
Diffie is a fellow of the Marconi Foundation, fellow of the Computer History Museum, and an inductee of both the National Inventors Hall of Fame and the Cybersecurity Hall of Fame. He is the reccipient of the National Computer Systems Security Award given jointly by the National Institute of Standards and Technology and the National Security Agency, the the Levy prize of the Franklin institute, and other awards. Diffie’s work and career are treated at length in the book Crypto by Steven Levy.