This textbook presents a detailed introduction to the essentials of networking and communications technologies. Revised and updated, this new edition retains the step-by-step approach of the original, organised to help those without a strong knowledge of the subject matter.  Features: provides chapter-ending summaries and review questions, an Appendix on TCP/IP packet formats and an expanded Glossary; supplies supplementary material at the associated Springer website, including teaching slides, solutions to the end-of-chapter questions and supplementary exercises with solutions; presents a greater emphasis on mobile computing and network security, and extended coverage of IPv6 (NEW); discusses networking models and standards, local area and wide area networks, network protocols, TCP/IP-based networks, network management and wireless communications; examines grid and cloud computing, microblogging, mobile ad hoc networks, near-field communication, Power over Ethernet and the Ground Positioning System (NEW).