Nowadays wireless technologies are developing faster and faster. Also the need for constantly high-speed Internet has lead to development of Worldwide Interoperability for Microwave Access (WiMAX or IEEE 802.16).WiMAX is a standards-based wireless technology that provides solutions to the "last mile" problem of Wireless Access. IEEE 802.16 is a new protocol that is being ratified now, and its security background and structure are under question. There are various security vulnerabilities is still exists in MAC layer as well as in physical layer of WiMAX. This book is going to address standard architecture and security aspects of WiMAX. In short, I expect this book to be of great use to practicing engineers, managers and executives, graduate students who want to learn about WiMAX, undergraduates who want to learn about wireless communications.