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C# Network Programming
by Richard Blum ISBN:0782141765
Sybex © 2003 (647 pages)
This book helps newcomers get started with a look at the basics of network programming as they
relate to C#, including the language s network classes, the Winsock interface, and DNS
resolution.
Table of Contents
C# Network Programming
Introduction
Part I - Network Programming Basics
Ch
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- The C# Language
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1
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- IP Programming Basics
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2
Ch
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- C# Network Programming Classes
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3
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- DNS and C#
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4
Part II - Network Layer Programing
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- Connection-Oriented Sockets
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5
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- Connectionless Sockets
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6
Ch
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- Using The C# Sockets Helper Classes
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7
Ch
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- Asynchronous Sockets
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8
Ch
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- Using Threads
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9
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Ch
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- IP Multicasting
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10
Part III - Application Layer Programming Examples
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- ICMP
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11
Ch
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- SNMP
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12
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- SMTP
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13
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- HTTP
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14
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- Active Directory
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15
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- Remoting
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16
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- Security
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17
Index
List of Figures
List of Tables
List of Listings
List of Sidebars
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Back Cover
On its own, C# simplifies network programming. Combine it with the precise instruction found in C# Network
Programming, and you ll find that building network applications is easier and quicker than ever.
This book helps newcomers get started with a look at the basics of network programming as they relate to C#,
including the language s network classes, the Winsock interface, and DNS resolution. Spend as much time here as
you need, then dig into the core topics of the network layer. You ll learn to make sockets connections via TCP, and
connectionless connections via UDP. You ll also discover just how much help C# gives you with some of your
toughest chores, such as asynchronous socket programming, multithreading, and multicasting.
Network-layer techniques are just a means to an end, of course, and so this book keeps going, providing a series of
detailed application-layer programming examples that show you how to work with real protocols and real network
environments to build and implement a variety of applications. Use SNMP to manage network devices, SMTP to
communicate with remote mail servers, and HTTP to Web-enable your applications. And use classes native to C#
to query and modify Active Directory entries.
Rounding it all out is plenty of advanced coverage to push your C# network programming skills to the limit. For
example, you ll learn two ways to share application methods across the network: using Web services and remoting.
You ll also master the security features intrinsic to C# and .NET features that stand to benefit all of your
programming projects.
About the Author
Richard Blum has spent 14 years as a network and system administrator for the US Department of Defense,
supporting a large network of workstations and servers. He holds a BS in Electrical Engineering and an MS in
Management Information Systems, both from Purdue University.
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C# Network Programming
Richard Blum
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ISBN: 0-7821-4176-5
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This book is dedicated to Sister Marie Imelda, C.S.C, who in the late 1970s fought and struggled to teach a
bunch of goofy high school kids how to program. Thanks, Sister. Trust in the Lord with all your heart and
lean not on your own understanding; in all your ways acknowledge him, and he will make your paths
straight. Prov. 3:5-6 (NIV)
Acknowledgments
First, all honor, glory, and praise goes to God, who through His Son, all things are possible, and who gives us the gift
of eternal life.
I would like to thank all the great people at Sybex for their help, guidance, and professionalism. Thanks to Denise
Santoro Lincoln, the Acquisitions Editor, for offering me the opportunity to write this book. Also, thanks to Carol
Henry, the Developmental Editor, for all her work guiding this book along and helping make my paragraphs make
sense.
Many thanks to Sally Engelfried, the Copy Editor, for turning my poor grammar into perfect sentences, and to Dan
Frumin, the Technical Editor, for going above and beyond the call of duty fixing my programs and pointing out my
technical blunders. Also, thanks to Carole McClendon at Waterside Productions for her help in arranging this book
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for me.
Finally, I would like to thank my parents, Mike and Joyce Blum, for their dedication and support, and my wife
Barbara and daughters Katie Jane and Jessica for their faith, love, and understanding, especially while I was writing
this book.
The quotation on the bottom of the front cover is taken from the sixty-third chapter of Lao Tzu s Tao Te
Ching, the classic work of Taoist philosophy. This particular verse is from the translation by D. C. Lau
(copyright 1963) and communicates the idea that one should confront the difficult while it is still easy and
accomplish a great task by a series of small acts.
It is traditionally held that Lao Tzu lived in the fifth century B.C. in China, during the Chou dynasty, but it is
unclear whether he was actually a historical figure. It is said that he was a teacher of Confucius. The
concepts embodied in the Tao Te Ching influenced religious thinking in the Far East, including Zen Buddhism
in Japan. Many in the West, however, have wrongly understood the Tao Te Ching to be primarily a mystical
work; in fact, much of the advice in the book is grounded in a practical moral philosophy governing personal
conduct.
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Introduction
Networks (and network programming) have come a long way over the past 20 years. In the early days of network
computing (the 80s), network programming was left to the advanced programmer, who typically built applications
using the C programming language in (mostly) Unix environments. Now, networks are everywhere, from large
corporations to small home users. With so many computers connected together via networks, network-aware
applications are an accepted necessity. Existing applications must incorporate network features to stay competitive in
the marketplace, and adding network communication to applications is essential. Network programs are used for
everything from children s games to advanced corporate database systems.
Network programming has always been a key feature of the Microsoft Windows operating system. Unfortunately,
you ve had to know advanced C or C++ programming concepts to utilize the network programming features in
Windows programs. Now, though, the .NET Framework languages simplify the task of adding network features to
your applications. The .NET libraries provide many network classes that can integrate network programming.
As a network administrator, I ve written many network programs using the C and Java languages for both Windows
and Unix platforms. Today s network management and security requirements make it essential to communicate with
network devices and track workstations on the network. Trying to quickly write clean network code can be difficult
when you are working within the structure of the C socket APIs (especially in WinSock), and running Java
applications is often a painful experience due to slow processing speeds and poor Windows support.
The C# language has solved many of my network programming problems by allowing me to quickly prototype and
deploy network applications using C# classes. Combining the C# Forms library to write the graphical code with the
C# Socket library to write the networking code makes creating professional network applications simple. With C#
network classes, what used to take a day to write often only takes an hour or less.
Who Should Read This Book
Obviously, if you are a C# programmer who is interested in creating network programs, this book is specifically
intended to help you out. I ve described each network C# class in detail, and you ll find lots of examples to help you
implement the classes in your own work. If you have never before written a network program, I ve included useful
explanations of the concepts and ideas behind network programming in general, including common techniques for
passing data between network devices.
You may already be familiar with writing network programs using other languages, such as C, C++, or Java. In that
case, you ll be interested in seeing how easy it is to do this with the C# language.
If you are new to the C# language, the first chapter describes the basics of creating and compiling C# programs. You
may want to skip other chapters in the first part of the book, which discuss network programming basics, and dive
right into the C#-specific network programming classes.
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How This Book Is Organized
This book is organized into four separate sections that cover a particular aspect of network programming.
Part I: Network Programming Basics
The first four chapters are intended for programmers just starting out in network programming and looking for some
background information about how network programming works and the pieces that are required for network
programming.
Chapter 1, The C# Language, provides some basic information for the reader new to C#, such as which C#
package to use for development work and how to compile C# programs.
Chapter 2, IP Programming Basics, demonstrates how network programming has evolved from the Unix world to
the world of Windows, via the WinSock interface, and how .NET uses the WinSock interface to access network
resources.
Chapter 3, C# Network Programming Classes, offers a quick introduction to the entire C# network libraries and
shows the basic formats of the classes.
Chapter 4, DNS and C#, rounds out the introductory section by showing network novices how DNS can resolve
host addresses and how to use the C# DNS classes.
Part II: Network Layer Programming
The next group of chapters presents the core of network programming topics in the book. Each of these chapters
discusses a major topic using in creating C# network programs.
Chapter 5, Connection-Oriented Sockets, starts the discussion of network programming by introducing stream
programming using TCP. In addition to the standard C# Socket class used for stream programming, common pitfalls
are discussed to help you create stream programs that will work on real networks.
Chapter 6, Connectionless Sockets, discusses how to use the Socket class to create UDP applications. In addition
to showing you how to create UDP applications, this chapter also discusses pitfalls related to UDP programming and
shows examples of creating applications that will withstand the problems inherent in real networks.
Chapter 7, Using the C# Socket Helper Classes, discusses the C# TcpClient, TcpListener, and UdpClient classes.
These are special classes in .NET to help programmers create network programs with minimal effort. This chapter
also discusses the basics of sending different data types across the network.
