This book attempts to provide a unified overview of the broad field of data and computer communications. The organization of the book reflects an attempt to break this massive subject into comprehensible parts and to build, piece by piece, a survey of the state of the art. The book emphasizes basic principles and topics of fundamental importance concerning the technology and architecture of this field and provides a detailed discussion of leading-edge topics.
The following basic themes serve to unify the discussion:
- Principles: Although the scope of this book is broad, there are a number of basic principles that appear repeatedly as themes and that unify this field. Examples are multiplexing, flow control, and error control. The book highlights these principles and contrasts their application in specific areas of technology.
- Design approaches: The book examines alternative approaches to meeting specific communication requirements.
- Standards: Standards have come to assume an increasingly important, indeed dominant, role in this field. An understanding of the current status and future direction of technology requires a comprehensive discussion of the related standards.
PLAN OF THE TEXT
The book is divided into five parts:
In addition, the book includes an extensive glossary, a list of frequently used acronyms, and a bibliography. Each chapter includes problems and suggestions for further reading.
The book is intended for both an academic and a professional audience. For the professional interested in this field, the book serves as a basic reference volume and is suitable for self-study. As a textbook, it can be used for a one-semester or two-semester course. It covers the material in the Communication and Networking core course of the joint ACM/IEEE Computing Curricula 2001. The chapters and parts of the book are sufficiently modul to provide a great deal of flexibility in the design of courses. The following are suggestions for course design:
- Fundamentals of Data Communications: Parts One (overview) and Two (data communications) and Chapters 10 and 11 (circuit switching, packet switching, and ATM).
- Communications Networks: If the student has a basic background in data communications, then this course could cover Parts One (overview), Three (WAN), and Four (LAN).
- Computer Networks: If the student has a basic background in data communications, then this course could cover Part One (overview), Chapters 6 and 7 (data communication techniques and data link control), and Part Five (protocols).
In addition, a more streamlined course that covers the entire book is possible by eliminating certain chapters that are not essential on a first reading. Chapters that could be optional are Chapters 3 (data transmission) and 4 (transmission media), if the student has a basic understanding of these topics; Chapter 8 (multiplexing); Chapter 9 (spread spectrum); Chapters 12 through 14 (routing, congestion control, cellular networks); Chapter 18 (internetworking); and Chapter 21 (network security).
INTERNET SERVICES FOR INSTRUCTORS AND STUDENTS
There is a Web site for this book that provides support for students and instructors. The site includes links to other relevant sites, transparency masters of figures in the book, and sign-up information for the book's Internet mailing list. The Web page is at WilliamStallings.com/DCC/DCC7e.html; see the section, "Web Site for Data and Computer Communications," preceding the Table of Contents, for more information. An Internet mailing list has been set up so that instructors using this book can exchange information, suggestions, and questions with each other and with the author.
PROJECTS FOR TEACHING DATA AND COMPUTER COMMUNICATIONS
For many instructors, an important component of a data communications or networking course is a project or set of projects by which the student gets hands-on experience to reinforce concepts from the text. This book provides an unparalleled degree of support for including a projects component in the course. The instructor's manual not only includes guidance on how to assign and structure the projects, but also includes a set of suggested projects that covers a broad range of topics from the text, including research projects, simulation projects, analytic modeling projects, and reading/report assignments. See Appendix D for details.
The book includes a brief description of Sockets (Appendix C), with a more detailed description available at the book's Web site. The Instructors manual includes a set of programming projects. Sockets programming is an "easy" topic and one that can result in very satisfying hands-on projects for students.
WHAT'S NEW IN THE SEVENTH EDITION
This seventh edition is seeing the light of day less than 4 years after the publication of the sixth edition. During that time, the pace of change in this field continues unabated. In this new edition, I try to capture these changes while maintaining a broad and comprehensive coverage of the entire field. To begin the process of revision, the sixth edition of this book was extensively reviewed by a number of professors who teach the subject. The result is that, in many places, the narrative has been clarified and tightened, and illustrations have been improved. Also, a number of new "field-tested" problems have been added.
Beyond these refinements to improve pedagogy and user-friendliness, there have been major substantive changes throughout the book. Every chapter has been revised, new chapters have been added, and the overall organization of the book has changed. Highlights include:
- Wireless communications and networking: There is a significant increase in the amount of material on wireless communications, wireless networks, and wireless standards. The book now devotes one chapter each to spread spectrum technology, cellular wireless networks, and wireless LANs.
- Gigabit Ethernet: The discussion on Gigabit Ethernet has been updated and an introduction to 10-Gbps Ethernet has been added.
- Differentiated services: There have been substantial developments since the publication of the sixth edition in enhancements to the Internet to support a variety of multimedia and time-sensitive traffic. The most important development, and perhaps the most important vehicle for providing QoS in IP-based networks, is Differentiated Services (DS). This edition provides thorough coverage of DS.
- Guaranteed frame rate (GFR): Since the sixth edition, a new ATM service has been standardized: GFR. GFR is designed specifically to support IP backbone subnetworks. This edition provides an explanation of GFR and examines the mechanisms underlying the GFR service.
- Multiprotocol label switching (MPLS): MPLS has emerged as a fundamentally important technology in the Internet and is covered in this edition.
- TCP/IP details: A new background chapter on TCP and IP has been added, pulling together material scattered throughout the sixth edition. This material is vital to an understanding of QoS and performance issues in IP-based networks.
In addition, throughout the book, virtually every topic has been updated to reflect the developments in standards and technology that have occurred spce the publication of the fifth edition.
--This text refers to an alternate