The text consists of ten chapters. It starts with a general overview of LAN and of the book. Chapter 2 deals with the OSI reference model, while Chapter 3 addresses some basic concepts in data communication. Chapter 4 focuses on the topologies and transmission media used in LAN. The mathematical foundation of queuing theory needed later is provided in Chapter 5. Chapter 6 deals with performance analysis of ALOHA, CSMA/CD, token ring, and token bus. Chapter 7 is essentially on network interconnecting devices such as bridges and routers. Chapter 8 is on network reliability modelsand improvement techniques. Chapter 9 is on network security issues such as data encryption standard and cryptography. The last chapter focuses on applications of LAN technology such as variations of IEEE 802.3, CSMA/CD, MAP/TOP, and FDDI. The book also includes five appendixes containing units, mathematical relations, Ethernet, probability theory,and Markov chain. This book aims to cover a broad spectrum of topics on LAN’s in a clear and logical manner and this is its strength. Discussion is succinct and derivations are minimal. The author writes as one from industry who is also in touch with academe. The students appreciate the thorough explanations (and sometimes with examples) of basic concepts such as the open system interconnect (OSI) model, data encoding, bandwidth, channel capacity, frequency-division multiplexing (FDM) and time-division multiplexing (TDM), message- and packet-switching, and Little’s formula.