The Linux TCP/IP Stack: Networking for Embedded Systems
by Thomas F. Herbert
Charles River Media © 2004 (600 pages)
ISBN:1584502843
Written for embedded systems programmers and engineers, as well as
networking professionals, this in-depth guide provides an inside look at the
entire process of implementing and using the Linux TCP/IP stack in embedded
systems projects.
Table of Contents
The Linux TCP/IP Stack—Networking for Embedded Systems
Chapter 1 -
Introduction
Chapter 2 -
Broadband Networking Protocols of Yesterday and Today
Chapter 3 -
TCP/IP in Embedded Systems
Chapter 4 -
Linux Networking Interfaces and Device Drivers
Chapter 5 -
Linux Sockets
Chapter 6 -
The Linux TCP/IP Stack
Chapter 7 -
Socket Buffers and Linux Memory Allocation
Chapter 8 -
Sending the Data from the Socket through UDP and TCP
Chapter 9 -
The Network Layer, IP
Chapter 10 -
Receiving Data in the Transport Layer, UDP, and TCP
Chapter 11 -
Internet Protocol Version 6 (IPv6)
Appendix A
-
RFCs
Appendix B
-
About the CD-ROM
Bibliography
Index
List of Figures
List of Tables
The Linux TCP/IP Stack—Networking for
Embedded Systems
Thomas F. Herbert
Copyright 2004 by CHARLES RIVER MEDIA, INC.
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Thomas Herbert. The Linux TCP/IP Stack: Networking for Embedded Systems.
ISBN: 1-58450-284-3
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Library of Congress Cataloging-in-Publication Data
Herbert, Thomas (Thomas F.)
The Linux TCP/IP stack : networking for embedded systems / Thomas Herbert.— 1st ed.
p. cm.
ISBN 1-58450-284-3 (pbk. with cd-rom : alk. paper)
1. Linux. 2. Operating systems (Computers) 3. TCP/IP (Computer network protocol) A04.
Embedded computer systems. I. Title.
QA76.73.O63H47 2004
005.4’32—dc22
2004005014
Printed in the United States of America
04 7 6 5 4 3 2 First Edition
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Acknowledgments
While working on this book, I often thought of this endeavor as a lonely and particularly solitary
effort in attempting to unravel this complex and intricate body of software. In fact, though, I
have not been alone. Many influenced me to take on this project, and there are many without
whom I would not have been able to complete this task. I owe enormous gratitude to the many
people who have helped me along the path that led to this book, some of whom are mentioned
here.
First and foremost, I am indebted to my late parents, George and Dorothy Herbert. My father is
my main inspiration. He was a self-taught and very intelligent man with a strong life-long
interest in learning, literature, and writing. He brought me up in a house filled with books, and at
a very young age, I came to see the value of the printed word. Both my father and my mother
always told me that I could do anything and accomplish anything I put my mind to. Whenever I
stumble along the way, I remember my mother’s advice that with hard work, courage, and
creativity I can achieve any goal in which I believe.
I feel some gratitude to the embedded development community, which has been my profession
and source of income for most of the last 20 years. There have been a few key people in my
business and professional life who guided my path leading to my publishing activities and
ultimately to the writing of this book. I first thought about publishing articles about networking
in a commercial magazine after talking with Marty Leisner. Marty was a coworker of mine at
Xerox in the mid-1990s and an early proponent of the open-source philosophy. In addition, at
that time, I polished my writing skills when my manager, Hugo Buitano, would often ask for my
assistance to produce “hand crafted” e-mails when a complex and sensitive subject would come
up and needed handling accurately but with tact and diplomacy. I should also mention Lindsey
Vereen, editor of “Embedded Systems Programming,” who noticed my paper in the conference
proceedings and said that it was “well written for a conference paper.”
I have enormous respect and am extremely grateful to all of the people involved in the open-
source community and the Linux development project. The open-source movement grows in
strength all the time and has defined a new way of doing business in our industry. It is opening
markets around the world and proving to be an effective counterweight to the monopolistic
practices of some major players in our industry. I am indebted to pioneers in the open-source
movement such as Richard Stallman, who begin the Free Software Foundation and first used the
term free software, meaning freedom to create, modify, and improve. I am particularly indebted
to Linux Torvalds, the original developer of the Linux kernel.
In addition, there are all the people involved in the long development and improvement of
TCP/IP, beginning with the late Jon Postel who was the editor of the RFCs for many years. He
authored many of the early RFCs specifying how the protocols written about in this book
actually work. For more information about Jon Postel, go to the Postel Center at the University
of Southern California, www.postel.org/postel.html. I also am grateful to Gary R. Write and W.
Richard Stevens, authors of what is clearly the definitive work about the internal functioning of
any TCP/IP implementation. In this book, I hope I am at least coming close to living up to the
high standard they have created. Finally, I extend my thanks to the contributors to the Linux
TCP/IP implementation. There are too many to mention here, but I must name one person in
particular, Alexey Kuznetsov, who has contributed a huge volume of well-documented high-
quality professional code to Linux TCP/IP.
I have benefited by the association with the highly professional staff at Charles River Media,
which started when David Pallai, the president and founder of Charles River Media, first
approached me and invited my book proposal. James Walsh, the acquisitions editor, has been
with me during the entire process. Jim has been very patient with me as I faced unanticipated
problems delaying the work and needed extra time to dig out the bits or follow all the threads
through complexities in the code. He has supported me through changes in goals for this project
with the addition of IPv6 and the 2.6 kernel. Bryan Davidson, the production coordinator, has
been extremely helpful. He took the extra time to answer my arcane formatting questions and
showed flexibility as we moved this work through production.
I want to acknowledge the work of my reviewers, Jim Lieb and David McLain. Jim’s review of
the first part of the book helped me to focus on the practical needs of my readers and the market.
I want to extend special thanks to David, who went way beyond the call of duty. His knowledge
of the Linux kernel code, computer networking, memory allocation methods, and good software
engineering practice was very helpful. He carefully checked all my explanations against the
Linux source code and was not shy about pointing out inaccuracies, mistakes, and places where
the text needed clarification.
Finally, there is my family, particularly my 14-year-old son, Aaron, and my wife of many years,
Carol. Both of them have suffered my absences during the creation of this book. They have been
very tolerant and patient and I apologize to them for the many hours that I spent hunched over
this laptop ignoring their needs. They have been patient with me while tasks went undone and
remained so when basketball games and other events were missed while I struggled to meet my
deadlines. Carol never stopped believing in my ability to complete this task throughout this 14-
month project. Carol is an inspiration to me in so many ways; even when the amount of work
seemed overwhelming, she never lost faith in me.
