Author | Claude E. Shannon |
---|---|
Language | English |
Subject | Cryptography |
Publication date | 1949 |
Publication place | United States |
"Communication Theory of Secrecy Systems" is a paper published in 1949 by Claude Shannon discussing cryptography from the viewpoint of information theory.[1] It is one of the foundational treatments (arguably the foundational treatment) of modern cryptography.[2] His work has been described as a "turning point, and marked the closure of classical cryptography and the beginning of modern cryptography."[3] It has also been described as turning cryptography from an "art to a science".[4] It is also a proof that all theoretically unbreakable ciphers must have the same requirements as the one-time pad.
The paper serves as the foundation of secret-key cryptography, including the work of Horst Feistel, the Data Encryption Standard (DES), Advanced Encryption Standard (AES), and more.[5] In the paper, Shannon defined unicity distance, and the principles of confusion and diffusion, which are key to a secure cipher.[6]
Shannon published an earlier version of this research in the formerly classified report A Mathematical Theory of Cryptography, Memorandum MM 45-110-02, Sept. 1, 1945, Bell Laboratories.[7][8] This report also precedes the publication of his "A Mathematical Theory of Communication", which appeared in 1948.