In Internetwork Mobility, the developers of the Cellular Digital Packet Data (CDPD) standard present a complete, authoritative guide to wireless data: both the technology and the highly profitable business applications it makes possible. They focus on CDPD's wide area data networking capabilities, demonstrating how CDPD can make mobile devices accessible for data transmissions virtually anywhere, anytime, without complex gateways or proprietary application interfaces. If you're new to wireless data communications, the authors present the fundamentals of cellular communications and mobility - the background you need before you can understand CDPD. Next, they cover CDPD architecture and protocols in detail, and show how CDPD solves the problems associated with reliable transmission of digital data. CDPD's security capabilities, including encryption and authentication, are also presented, as well as CDPD's comprehensive system management framework, and CDPD's capabilities for usage accounting, message handling, and directory services. Compare CDPD with non-cellular approaches to mobile data networking, including infrared, narrowband RF, spread spectrum, and other systems. And understand where CDPD is headedincluding recently-standardized extensions, such as limited size messaging and circuit-switched CDPD, and new airlink technologies for CDPD.