Chapter 9. Basic Network Programming

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Network programming in one shape or form is an essential aspect of building distributed systems. It involves enabling communication over a network and the passing of data between processes running on different computers. Numerous technologies and paradigms have emerged to take the grunge work out of building distributed systems and encapsulating repetitive low-level boilerplate code into higher-level abstractions. Examples include COM+ in the Microsoft world and Enterprise JavaBeans (EJB) in the Java arena. These technologies have allowed developers to concentrate on the business logic of their applications rather than having to worry about how individual bytes of data travel from one machine to another.

High-level paradigms have their limitations, however. Even though they're excellent for constructing systems in which all computers run the same software and are based on the same platform, they do not cope as well in less homogenous environments, which might force the developer to rely on lower-level concepts.

Microsoft .NET is a wonderful example of a development environment that exposes a rich variety of APIs for handling network programming. Because integrating with other systems often involves resorting to lower-level services, this chapter will look at using sockets over TCP/IP with .NET. We'll also discuss the implementation of HTTP in .NET and how you can exploit it for building portable Internet and intranet systems. In later chapters, we'll look at some of the upper layers of functionality that .NET provides, including the Remoting architecture and Web services.

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