Computer Networking provides a top-down approach to this study by beginning with applications-level protocols and then working down the protocol stack. Focuses on a specific motivating example of a network-the Internet-as well as introducing students to protocols in a more theoretical context. New short "interlude" on "putting it all together" that follows the coverage of application, transport, network, and datalink layers ties together the various components of the Internet architecture and identifying aspects of the architecture that have made the Internet so successful. A new chapter covers wireless and mobile networking, including in-depth coverage of Wi-Fi, Mobile IP and GSM. Also included is expanded coverage on BGP, wireless security and DNS. This book is designed for readers who need to learn the fundamentals of computer networking. It also has extensive material, on the very latest technology, making it of great interest to networking professionals.