Prof. Martin Hellman

1. Diffie, W. and M. Hellman. “New Directions in Cryptography.” IEEE Transactions on Information Theory Vol. IT-22, no. 6, November 1976, pp. 644-654. [The first part of block quote in the biographical profile is from p. 644, while the continuation (on authentication) is from p. 649.]

This article underpins public-key cryptography and is generally viewed as the principal basis of the many distinguished awards Diffie and Hellman have received, including the 2015 ACM Turing Award.  It represents a brilliant achievement that solved the problem of key distribution and digital signatures (authentication), setting in motion the developments—especially the RSA algorithm—that have had a profound impact on encrypted communication and digital authentication.

2. Diffie, W. and M.E. Hellman. “Exhaustive Cryptanalysis of the NBS Data Encryption Standard.” Computer vol. 10  June 1977, pp. 74-84.

This is the most extensive of Hellman and Diffie’s early critiques of the National Bureau of Standard’s Data Encryption Standard or DES.  In this paper they give point-­by­-point responses to objections others raised regarding their criticism of the Data Encryption Standard.

3. Hellman, M.E. “The Mathematics of Public-Key Cryptography.” Scientific American vol. 241, August 1979, pp. 146-157.

Presents the mathematics of public-key cryptography in relatively accessible form for a scientifically literate audience.  It also offers important context to the pre-history and early response to Diffie-Hellman’s public-key cryptosystem.  Hellman now cautions that this article's "emphasis on trap door knapsacks, which were later found to be insecure" means that it should not be relied on.

4. Hellman, M.E. Oral History Interview, conducted by Jeffrey R. Yost, 22 November 2004, Stanford, California. CBI OH 375. Charles Babbage Institute, University of Minnesota.

This extensive career-spanning (58 page) oral history I conducted with Martin E. Hellman is the most comprehensive publicly available interview with him.  It is the source of all quotes in this biography, except where otherwise noted.

5. Levy, S. Crypto: How the Code Rebels Beat the Government—Saving Privacy in the Digital Age (New York: Viking, 2001).

This engaging book tells the story of the development of public-key cryptography by Diffie and Hellman, as well as public-key contributions made by Ralph Merkle and MIT scientists and mathematicians Ronald Rivest, Adi Shamir, and Leonard Adleman.

6. Schneier, B. Applied Cryptography: Protocols, Algorithms, and Source Code in C (New York: John Wiley and Sons, Inc., 1994). [Quoted material and statement on the Diffie-Hellman protocol for public-key cryptography is from p. 275.]

This textbook on cryptography (praised by Martin Hellman) offers a very clear and concise statement of the Diffie-Hellman protocol for their public-key cryptosystem.

7. Singh, S. The Code Book: The Evolution of Secrecy from Mary Queen of Scots to Quantum Cryptography. (New York, Doubleday, 1999).

Before switching to become a journalist, producer, and science/mathematics writer for popular audiences Singh completed his doctorate in physics from the University of Cambridge.  This is a well-informed engaging work spanning the long history of cryptography—including a useful chapter on the history of public-key cryptography (“Alice and Bob Go Public”).  It contains biographical information on both Hellman and Diffie and their great achievement with public-key, and unlike some works, also gives proper credit to the insightful research of Ralph Merkle in this area.

8. Yost, J.R. “A History of Computer Security Standards,” in K. de Leeuw and J. Bergstra, eds. The History of Information Security: A Comprehensive Handbook. Amsterdam, Elsevier Science, 2007, 595-622.

This addresses the history of standards on both the encryption side (DES) and operating system side (work of the Department of Defense/NSA National Computer Security Center)—drawing on interviews I conducted with Willis Ware, Martin Hellman, James Bidzos, as well as many other resources.

Jeffrey R. Yost