0.1 OUTLINE OF THE BOOK The book is organized into two units. Unit One provides a survey of the funda- mentals of data communications, networks, and Internet protocols. Unit Two covers more advanced or difficult topics in data communications and networks, and provides a more comprehensive discussion of Internet protocols and operation. Unit One is organized into five parts: Part One. Overview: Provides an introduction to the range of topics covered in the book. This part includes a general overview of data communications and networking, and a discussion of protocols and the TCP/IP protocol suite. Part Two. Data Communications: Presents material concerned primarily with the exchange of data between two directly connected devices. Within this restricted scope, the key aspects of transmission, transmission media, error detection, link control, and multiplexing are examined. Part Three. Wide Area Networks: Examines the technologies and protocols that have been developed to support voice, data, and multimedia communications over long-distance networks. The traditional technologies of packet switching and circuit switching, as well as the more contemporary ATM and cellular net- works, are examined. Part Four. Local Area Networks: Explores the technologies and architectures that have been developed for networking over shorter distances. The transmis- sion media, topologies, and medium access control protocols that are the key ingredients of a LAN design are explored. This is followed by a detailed discus- sion of Ethernet and Wi-Fi networks. Part Five. Internet and Transport Protocols: Discusses protocols at the Internet and Transport layers. Unit Two consists of three parts: Part Six. Data Communications and Wireless Networks: Treats important topics in these areas not covered in Unit One. Part Seven. Internetworking: Examines a range of protocols and standards related to the operation of the Internet, including routing, congestion control, and quality of service. Part Eight. Internet Applications: Looks at a range of applications that operate over the Internet. In addition, there is an online Part Nine. Security: It covers security threats and techniques for countering these threats. A number of online appendices cover additional topics relevant to the book.