Preface

Fast communication between the digital and physical worlds is made possible by the Internet of Things (IoT). This rapid growth has made everything in the world able to get connected. Therefore, securing this growing amount of data while it is being transmitted will be essential. Cryptography is a crucial instrument used to protect this data.

The study of encrypting and decrypting data using mathematics is known as cryptography. With cryptography, you can send or keep confidential data over unsecured networks, such as the Internet, so that only the intended receiver can read it. In our IoT-connected world, cryptography is utilized to encrypt all transferred data and authenticate individuals, devices, and other gadgets. The study of data security is known as cryptography, and the science of deciphering and intercepting secure communication is known as cryptanalysis. Cryptography and cryptanalysis together are said to be cryptology.

Cryptography has crept into everything, from Web browsers and e-mail programs to cell phones, bank cards, and cars. Soon, we will see many new exciting applications for cryptography such as radio frequency identification (RFID) tags for anti-counterfeiting. As a consequence of the pervasiveness of crypto algorithms, an increasing number of people must understand how they work and how they can be applied in practice. This book addresses this issue by providing a comprehensive introduction to modern applied cryptography that is equally suited for students and practitioners in industry.

Much of the focus is on practical relevance by introducing most crypto algorithms that are used in modern real-world applications. In addition to crypto algorithms, attention is also given to important cryptographic protocols, modes of operation, security services, and key establishment techniques. Timely topics include lightweight ciphers, which are optimized for constrained applications.

The chapters in the first section of the book explore the latest developments, methods, approaches, and applications of cryptography in a wide variety of fields and endeavors. This section provides researchers, academicians, and readers of various backgrounds and methods with an in-depth discussion of the latest advances. It consists of 4 chapters from academicians, practitioners, and researchers in the field of cryptography.

In the second section, the book discusses biometrics. Biometrics is a fascinating discipline that uses unique characteristics of the human body for the identification and verification of individuals. This section explores the diverse applications of biometrics, from unlocking mobile phones to access control in high-security facilities. Through practical examples and clear explanations, we will discover how biometrics

is transforming the way we interact with technology and how it ensures greater security in our society. Welcome to a world where your body is your most secure identification.

## **Dr. Sudhakar Radhakrishnan**

Section 1

Cryptography

Professor, Department of Electronics and Communication Engineering, Dr. Mahalingam College of Engineering and Technology, Tamil Nadu, India

**Dr. Carlos M. Travieso-González** Professor, Department of Signals and Communication, Institute for Technological Development and Innovation in Communications, University of Las Palmas, Gran Canaria, Spain

Section 1 Cryptography

## **Chapter 1**
