Paul Kocher

Paul Kocher Marconi Society

Awarded the Marconi Prize in 2019

Cited for developing SSL/TLS and other contributions to the security of communications.

Presented at the Hiller Aviation Museum in San Carlos, CA

Dr. Kocher is the former President of Cryptography Research, a Division of Rambus. He is recognized as the “Father of SSL” or Secure Sockets Layer. SSL and its successor, Transport Layer Security (TLS) are protocols for establishing and encrypting links between network computers. These protocols enable network participants to authenticate themselves using digital certificates and protects the data they exchange against eavesdropping and tampering.

“By addressing the need for end-to-end confidentiality and authenticity —which the Internet’s early developers deliberately omitted from the unclassified design —Kocher’s and Elgamal’s joint efforts played a critical role in enabling further development and scaling of the Internet,” says Dr. Vinton Cerf, Chair of the Marconi Society.

Kocher did not initially set out to become a cryptographer. He came to Stanford University to study biology in order to become a veterinarian. There he met Marty Hellman (2000 Marconi Prize recipient and co-inventor of Public Key Encryption) who encouraged Kocher’s involvement in several cryptographic initiatives. One of the initiatives Hellman suggested to Kocher was developing SSL at Netscape with Kocher’s co-recipient of the 2019 Marconi Prize, Tahel Elgamal. As an undergraduate, Kocher spent summers at RSA Labs and did consulting work during the school year, including numerous security evaluation projects for Microsoft. After finishing his undergraduate degree, he co-founded the company ValiCert, which went public in 2000. He also started and ran Cryptography Research, initially focusing on cryptography consulting (although later the company expanded into other products, and was acquired by Rambus in 2011).

In November 1996, Elgamal and Kocher published a public description of how two computers could establish an encrypted channel so that anyone could create a secure tunnel between two machines.

The elegance of SSL 3.0 is undeniable. In addition to enabling security for non-technical users, Kocher’s design efforts also anticipated that future research would lead to new algorithms, requirements and vulnerabilities to attacks. SSL 3.0’s longevity is due to its ability to negotiate sessions in a way that allows implementers to eliminate algorithms identified as weak and add support for new, stronger ones. The genius of this design is that it doesn’t break compatibility or require simultaneous upgrades of servers. And, it is still evolving; as new bugs or vulnerabilities are discovered, the technology has proved its value through its ability to change as needed.

Beyond SSL/TLS, Kocher has made significant contributions to the practice of cryptography, including his discovery of the “Spectre” class of vulnerabilities in microprocessors.

Kocher is a member of the U.S. National Academy of Engineering, serving on the Forum on Cyber Resilience. He is also a Fellow of the International Association for Cryptologic Research and serves on the