Chapter Summary

Networks exist to provide network services to the users of the network. Although this chapter certainly did not describe all the network applications available in a typical network, it did describe the most popular types of applications. Table 2-1 lists those network applications.

Table 2-1. Network-Based Applications Covered in This Chapter

Service	Description
File services	Files are stored on a computer, called a file server. Other computers, called clients, can read and write to these files, without needing to make a local copy of the file on the client disk drive. This service is typically transparent to the end user.
Print services	Printers are connected to a computer, called a print server. Client computers can send print output to the print server, which in turn prints the files on the printer. This service is typically transparent to the end user.
Web services	The server stores a variety of information, including text, graphics, animation, images, video, and audio. The end user uses a web browser to request the information from the server. The server returns the information, which is displayed by the web browser.
E-mail	An end user creates an e-mail using an e-mail client program and sends the e-mail to a particular person. E-mail servers aid the e-mail delivery process.
File transfer service	Files are also stored on a server. This allows other (client) computers to copy files from the server onto their local disk drives and to replace the contents of files on the file server with files on the client's local disk drives.

File and print services can, and typically do, hide the existence of the network from the end user community. The transparent nature of these applications means that the end user can perform the needed tasks without necessarily knowing whether he is using the network. Conversely, web, e-mail, and file transfer services, by definition, expect that the end user knows that the network exists.