The authors build upon the popular first edition by combining pre-existing network design fundamentals with new material on LAN devices and topologies, wireless local networks, and LAN internetworking issues. This new edition has two parts. The first focuses on WANs; the second focuses on LANs. Because Ethernet emerged victorious in the LAN war, the second section pays particular attention to Ethernet design and performance characteristics. The book includes a number of practical networking problems and their solutions, along with examples of methods needed to perform economic comparisons among differing communications services and hardware configurations.