"Communication Theory of Secrecy Systems" is a paper published in 1949 by
Claude Shannon
Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, computer scientist, cryptographer and inventor known as the "father of information theory" and the man who laid the foundations of th ...
discussing
cryptography
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), ...
from the viewpoint of
information theory
Information theory is the mathematical study of the quantification (science), quantification, Data storage, storage, and telecommunications, communication of information. The field was established and formalized by Claude Shannon in the 1940s, ...
. It is one of the foundational treatments (arguably ''the'' foundational treatment) of modern cryptography. His work has been described as a "turning point, and marked the closure of classical cryptography and the beginning of modern cryptography." It has also been described as turning cryptography from an "art to a science". 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.
In the paper, Shannon defined
unicity distance, and the principles of
confusion and diffusion, which are key to a secure cipher.
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.
Bibliography of Claude Elwood Shannon
/ref> This report also precedes the publication of his " A Mathematical Theory of Communication", which appeared in 1948.
See also
* Confusion and diffusion
* Product cipher
* One-time pad
* Unicity distance
Notes
References
* Shannon, Claude. "Communication Theory of Secrecy Systems", '' Bell System Technical Journal'', vol. 28(4), page 656–715, 1949.
* Shannon, Claude. "A Mathematical Theory of Cryptography", Memorandum MM 45-110-02, Sept. 1, 1945, Bell Laboratories.
* https://www.itsoc.org/about/shannon
External links
Online retyped copy of the paper
History of cryptography
Cryptography publications
1945 in science
1949 documents
1949 in science
1945 documents
Mathematics papers
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