Almost half a century after McEliece proposed the first code-based cryptosystem, the field has reached maturity, and is now a major player in post-quantum standardization. This volume presents a wide view of the whole landscape, in a single unified treatment.

The book develops code-based cryptography starting from its fundamental principles and follows it all the way to the schemes now entering deployment. The opening chapters are designed to build the required background in both cryptography and coding theory, so that no prior familiarity with either is assumed. The treatment then proceeds through the main paradigms for encryption/key transport and signatures. Each chapter closes with a detailed presentation of the corresponding modern scheme, selected among the various candidates to the NIST’s Post-Quantum Cryptography (PQC) standardization effort.All schemes are described in a unified and simplified notation and accompanied by parameter sets, data sizes and timings.

Topics and features:

·Surveys various code families proposed for cryptographic use, from popular ones such as Goppa and MDPC codes, to various unsuccessful attempts

·Reports parameters, key and ciphertext sizes and cycle counts for every modern scheme under a single, explicitly stated measurement convention

·Covers the most recent cryptanalysis, including the square-code and quadratic-form distinguishers for Goppa codes and the syzygy distinguisher

·Gives self-contained descriptions of the decoding algorithms the schemes depend on, including Patterson, alternant and bit-flipping algorithms

·Follows the NIST and ISO standardization processes, explaining why individual schemes were selected, advanced or set aside

Aimed primarily at researchers and graduate students in cryptography, the book assumes only elementary linear algebra and is suited both to self-study and to a graduate course. It will equally serve researchers and graduate students in coding theory looking for an entry point into the cryptographic applications of their field, as well as implementers and security engineers who need a principled account of the schemes now entering standards.

Marco Baldi is Associate Professor in the Department of Information Engineering at Università Politecnica delle Marche, Ancona, Italy.Edoardo Persichetti is full Professor in the Department of Mathematics and Statistics at Florida Atlantic University, Boca Raton, FL, USA.

Marco Baldi is an Associate Professor in Telecommunications at the Department of Information Engineering of Univpm, where he also takes part in the Research and Service Center for Privacy and Cybersecurity (CRiSPY). He is a member of the management committee of the CINI Cybersecurity National Laboratory, and coordinates its local node at Univpm. He is founding member and scientific committee member of the National Cryptologic Association De Componendis Cifris. His research activity concerns communications reliability and security, with focus on coding and post-quantum cryptography. He is co-author of over 200 scientific papers published in international journals, book chapters and conference proceedings, one book and four patents. He is a member of AEIT, CINI, CNIT, GTTI, IEEE Communications Society, IEEE Information Theory Society, IEEE Signal Processing Society and an IEEE senior member. He has been vice-chair for the period 2021-2023 and chair for the period 2024-2025 of the IEEE Information Theory Society Italian chapter.

He is a member of the proposing team of 4 post-quantum cryptographic schemes that have been or are in standardization competitions: LEDAcrypt, CROSS, LESS and LEAST.

Edoardo Persichetti is Professor in the Department of Mathematics and Statistics at FAU, where he also acts as the director of the Center for Cryptology and Information Security (CCIS). He has been working on code-based cryptography for the best part of his academic career, with important contributions in the area. He has been deeply involved with the post-quantum standardization process, taking part in 8 proposals; of these, one was recently selected by NIST for the encryption/key transport functionality, (HQC), one was standardized by ISO (Classic McEliece), and one is still under consideration for digital signatures. His presence in the cryptographic community is of the first order, with several papers published in the major cryptography venues; he presently sits on the IACR board of directors, and served as general chair to the Eurocrypt 2026 conference. Together with Marco Baldi, he has launched the annual International Code-Based Cryptography workshop (CBCrypto) in 2019.