The bestselling classic continues to provide an enduring, practical understanding of networks and their building blocks through rich, example-based instruction. Using a bottom-up approach, Larry Peterson and Bruce Davie continue to focus on the why of network design. However, new with this edition comes the ability to focus from the application down. The "Systems Approach" adopted by the authors looks at "the big picture," encouraging readers to consider networks as interactive complex systems rather than rigidly defined layers. Thought-provoking and updated problems are presented at the beginning of each chapter so that the student or professional can start to solve the issue with each new detail learned. With every chapter building on the last, readers' knowledge of tools and resources continually enhances. By the end, readers thoroughly understand how complex networks and their applications are built. * Completely updated with new sidebar discussions that cover the deployment status of protocols described in the book. * Addition of sizeable number of new exercises and solutions. * Downloadable Opnet network simulation software and lab experiments manual. * New and revised instructor support material, including Powerpoint slides, eps version of figures appearing in the text; sample exams; lecture notes; UNIX sockets programming assignments.