Book excerpt: This new edition introduces the basic concepts in computer networks, blockchain, and the latest trends and technologies in cryptography and network security. The book is a definitive guide to the principles and techniques of cryptography and network security, and introduces basic concepts in computer networks such as classical cipher schemes, public key cryptography, authentication schemes, pretty good privacy, and Internet security. It features a new chapter on artificial intelligence security and the latest material on emerging technologies, related to IoT, cloud computing, SCADA, blockchain, smart grid, big data analytics, and more. Primarily intended as a textbook for courses in computer science, electronics & communication, the book also serves as a basic reference and refresher for professionals in these areas. FEATURES: Includes a new chapter on artificial intelligence security, the latest material on emerging technologies related to IoT, cloud computing, smart grid, big data analytics, blockchain, and more Features separate chapters on the mathematics related to network security and cryptography Introduces basic concepts in computer networks including classical cipher schemes, public key cryptography, authentication schemes, pretty good privacy, Internet security services, and system security Includes end of chapter review questions