The first author is a professor in the Department of Mathematics and head of the Crypto Group at the Technical University of Denmark; his main interests are the analysis and design of block ciphers, hash functions, and message authentication codes. The second author is a researcher in the Cryptography Research Group of Orange (France Télécom); his main interests are the design and analysis of symmetric cryptographic primitives, cryptographic techniques for constrained devices, and the deployment of cryptographic solutions. Both authors have taken lead roles in the related professional associations and academic conferences.

• Introduction.- Data Encryption Standard (DES).- Advanced Encryption Standard (AES).- Using Block Ciphers.- Brute-Force Attacks.- Differential Cryptanalysis.- Linear Cryptanalysis.- Advanced Topics.- A Short Survey and Five Prominent Ciphers.- Bibliography.

From the reviews: "Overall, this book provides a historical view of the essential work on the design and analysis of block ciphers. The book is well written and is appropriate for both beginners and experienced readers. Those who want more details about the rationale and philosophy behind block cipher design can use this book as an up-to-date reference." (Zheng Gong, ACM Computing Reviews, July 2012) "'The block cipher companion' is a well written handbook, wholly recommended. An excellent choice of examples and informal language make this handbook an excellent choice for beginners, guiding the reader from simple cipher techniques and cryptanalysis towards more advanced ideas. ... Professionals will find the book to be a systematic collection of ideas, and, in particular, a thorough bibliography and a short survey of block ciphers evolution." (Jerzy Zurawiecki, Zentralblatt MATH, Vol. 1243, 2012)