Gilbert S. Vernam

Gilbert Sandford Vernam was an American engineer associated with a 1917 teleprinter cipher design. His system combined a message with key material carried on paper tape, establishing the design generally known as the Vernam cipher.

Machine cryptography

The core idea was to combine corresponding message and key symbols, then use the same key material for recovery. In collaboration with Joseph Mauborgne’s work on truly random key material, the approach became associated with the one-time pad.

Lasting significance

Vernam’s patent records the engineering implementation. Later information theory gave the one-time-pad construction a formal account of perfect secrecy under its strict conditions.

In memoriam

Vernam died in 1960. His work remains an important part of the history of practical cryptographic engineering.

Timeline

• 1890-04-03Born in the United States.
• 1917Develops a teleprinter cipher system.
• 1919Receives U.S. Patent 1,310,719 for a secret signaling system.
• 1949Claude Shannon publishes a formal proof of perfect secrecy for the one-time-pad model.
• 1960-02-07Dies in the United States.