everything I can to maintain the essential character of the book while making it better. The Domain
Name Service material has been updated to cover the latest version of the BIND 4 software. The email
configuration is now based on sendmail version 8, and the operating system examples are from the
current versions of Solaris and Linux. The routing protocol coverage has been expanded to include Open
Shortest Path First (OSPF) and Border Gateway Protocol (BGP). I have also added new topics such as
one-time passwords and configuration servers based on Dynamic Host Configuration Protocol (DHCP)
and Bootstrap Protocol (BOOTP). Despite the additional topics, the book has been kept to a reasonable
length.
The bulk of this edition is derived directly from the first edition of the book. To emphasize both that
times have changed and that my focus on practical information has not, I have left the introductory
paragraphs from the first edition intact.
Foreword from the First Edition
The Internet, the world's largest network, grew from fewer than 6,000 computers at the end of 1986 to
more than 600,000 computers five years later. [1] This explosive growth demonstrates the incredible
demand for network services. This growth has taken place despite a lack of practical information for
network administrators. Most administrators have been forced to content themselves with man pages, or
protocol documents and scholarly texts written from the point of view of the protocol designer. For
practical information, most of us have relied on the advice of friends who had already networked their
computers. This book addresses the lack of information by providing practical, detailed network
information for the UNIX system administrator.
[1] These figures are taken from page 4 of RFC 1296, Internet Growth (1981-1991), by M.
Lottor, SRI International. Read this book and you'll learn what an RFC is, and how to get
your own free copy!
Networks have grown so extravagantly because they provide an important service. It is in the nature of
computers to generate and process information, but this information is frequently useless unless it can be
shared with the people who need it. The network is the vehicle that enables data to be easily shared. Once
you network your computer, you'll never want to be stuck on an isolated system again.
The common thread that ties the enormous Internet together is TCP/IP network software. TCP/IP is a set
of communications protocols that define how different types of computers talk to each other. This is a
book about building your own network based on TCP/IP. It is both a tutorial covering the "why" and
"how" of TCP/IP networking, and a reference manual for the details about specific network programs.
