The book on Cryptography and Network Security is an introductory textbook for students in computer science, information technology, and cybersecurity. It focuses on the fundamentals of protecting information and securing communication over networks. The new edition builds upon its legacy with cutting-edge updates to address the rapidly evolving cybersecurity landscape. Designed for students, educators, and professionals, it combines foundational concepts with advanced insights, seamlessly integrating theoretical concepts with practical applications to empower readers to navigate the complexities of cryptography and cybersecurity in today?s digital age. Key Features: 1. Expanded Coverage of Emerging Threats: Includes the latest security challenges such as AI-driven attacks, ransomware-as-a-service, and supply-chain vulnerabilities, ensuring readers stay ahead in the evolving cybersecurity landscape. 2. Post-Quantum Cryptography Insights: Features an overview of NIST PQC candidates, lightweight cryptography for IoT, and lattice-based techniques, preparing readers for the future of secure communications. 3. Enhanced Practical Applications: Incorporates hands-on labs with OpenSSL, Python, Blockchain demos, and tools like Wireshark and Kali Linux, bridging theory with real-world implementation. 4. Updated Protocols and Architectures: Explores advancements in TLS 1.3, QUIC, Zero Trust Architecture, SASE, and IoT security protocols, providing comprehensive coverage of modern network security solutions.