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Cryptologic Hall of Honor

The Cryptologic Hall of Honor was created in 1999 to pay special tribute to the pioneers and heroes who rendered distinguished service to American cryptology.

The standards are high for induction into this great hall. The individuals honored were innovators over their entire careers or made major contributions to the structure and processes of American cryptology. The men and women who have been inducted to the Cryptologic Hall of Honor are all greats in the once silent world of cryptology.

In the early days of America's cryptologic effort, many of the "giants" did both Signals Intelligence and Information Assurance. They made important contributions to both offensive and defensive cryptology. As such, they were among the first inducted into the Cryptologic Hall of Honor.

Robert J. "Mac" McNelis

2015 Hall of Honor Inductee


Robert "Mac" McNelis joined NSA in 1964 as a math intern. Upon graduation from the intern program in 1967, he spent the rest of his career in the COMSEC organization. There, Mac became a leader in moving the directorate to more math-based procedures.

Responding to the "technical revolution" of the 1970s and 1980s, Mr. McNelis developed a science of system evaluation, now recognized as a "huge culture shift" in COMSEC practices. He directed a large staff in redesigning mathematical applications for crypto-security, and instituted a documentation program to improve evaluation quality. From 1984-1995 as Chief Evaluation Scientist, he was principal author of the Functional Security Requirements Specification document, which influenced the design and development of all U.S. government cryptographic devices.

In the same period, he developed measurable evaluation standards for security systems. When the COMSEC organization developed a requirements catalog of over 2,500 items, each based on an identified vulnerability in equipment, Mr. McNelis personally vetted each requirement. When the U.S. and UK discussed standards, he drove all significant change on the U.S. side during his tenure.

For thirty years, Mr. McNelis taught new crypto-mathematicians the fundamentals of system security. Known as an exacting taskmaster, he raised generations of Information Assurance Directorate technical personnel to work at the highest standards.

"Mac" built a critical field for the Information Assurance mission, and influenced two generations of NSA IAD analysts.