Appropriate for all introductory-to-intermediate courses in networking, telecommunications, or data communications. This book combines a thorough introduction to data communications and networking theory with a practical, "how-to" approach that enables students to apply the theory in real world environments. The text is organized into five logically-related parts, helping students discover how a data communications infrastructure builds from standards, to protocols, to working networks designed to solve a wide variety of business problems. Allen Dooley begins with fundamental concepts such as OSI and TCP/IP layered modeling and standards, as well as essential physical and data link layer details. He next turns to local area networking, introducing components, design considerations, topologies, logical IP addressing/subnetting, and network and application layer services. In Part III, he explains backbone, metropolitan, and wide area networks, covering topics ranging from Gigabit Ethernet to Backbone architectures, frame relay and ATM to DSL. Dooley then shows students how networking models, standards, protocols, devices, and other network elements can be integrated into a total total enterprise solution. In so doing, he addresses a wide range of technologies, from servers and storage area networks to VPNs, VoIP, firewalls, and encryption. Many topics are taught in the context of a running business case study. The book concludes with a preview of emerging network trends and technologies, addressing convergence, wireless, IPv6, and especially careers for data communications and networking professionals. Every chapter contains an Ethical Perspective section asking students to reflect on the ethical issues associated with the topics that have been covered. To support effective learning, Dooley provides learning objectives and detailed summaries, keyword highlighting, questions, exercises, and more.