This authoritative reference provides readers with a thorough understanding of IP Mobility using Mobile IPv6 and companion advanced mobility protocols including network mobility and fast handovers. It illustrates basic concepts and principles behind the IP Mobility architecture and covers the practices using detailed protocol description. Of particular importance is how mobile networking will support billions of devices without restricting applications or overburdening network infrastructures, and how it will support the movement of users from network to network without compromising security.