tailieunhanh - Networking and Network Programming

The goals of PC networking have been expanding over the last few years—from simple file and printer sharing to access of fax machines, modems, and enterprise-wide electronic mail systems. All the while, the essential goals of networking have always been to share resources and to provide a medium for communications. | Introduction to Networking 1 Networking and Network Programming 2 TCP IP Overview 3 WinSock Overview 4 Visual C Part ì Introduction to Networking The purpose of this book is to show you how to make network-aware applications that run on the Microsoft Windows and Windows NT operating systems using the Windows Sockets WinSock Application Programming Interface API . To that end several practical examples are examined that utilize the basic functionality of WinSock. Network operating systems such as Windows for Workgroups and Windows NT provide basic file and printer sharing services. This most basic level of functionality is provided out of the box. Network-aware applications are programs that use the capabilities of a collection of connected computers. Network-aware programs range from custom applications that transfer data among computers on a network to mainstream applications that enable electronic mail and remote database access. The WinSock API is a library of functions that a programmer can use to build these network-aware applications. WinSock has its roots in Berkeley sockets as introduced in the Berkeley Software Distribution of UNIX. WinSock uses the TCP IP Transmission Control Pro-tocol Internet Protocol suite which provides the formal rules of behavior that govern network communications between all computers running this particular computer networking protocol. Before I begin the examination of network programming look at the basics of computer networking in general. A network can be loosely defined as a collection of two or more computers that have some sort of communication path between them. A network can be loosely classified as either a local area network LAN or wide-area network WAN . The use of the terms LAN and WAN is somewhat misleading because which term you use is relative to the particular network installation you re describing. Generally speaking a LAN covers a much more geographically restricted area than does a WAN. Whereas a LAN may .