Principles of Digital Communication Systems & Computer Networks is designed as a textbook for digital communication systems, data communication and computer networks, and mobile computing. Part I deals with key topics such as information theory, transmission media, coding, error correction, multiplexing, multiple access, carrier modulation, PSTN, and radio communication. Part II goes on to cover the networking concepts, the ISO/OSI protocol architecture, Ethernet LAN, X.25 protocol, and TCP/IP protocol. Finally, Part III covers mobile computing, including radio paging, cellular mobile, GPS, CTI, unified messaging, and multimedia communication..