This chapter demonstrates how to connect Red Hat Linux to any TCP/IP-based network, such as the Internet, a private intranet, or a company extranet. The differences in how you connect have more to do with the network medium you use (that is, telephone lines, LAN router, and so on) than they do with whether you are connecting to the public Internet or a company's private network.
Connections to the Internet described in this chapter include a simple dial-up connection from your own Red Hat Linux system. The most popular protocols for making dial-up connections to the Internet are Point-to-Point Protocol (PPP) and Serial Line Internet Protocol (SLIP). This chapter focuses on PPP (it is more widely used than SLIP). It also builds on the procedures in Chapter 15 for creating your own Local Area Network (LAN) by teaching you how to connect your LAN to the Internet.
This chapter first provides an overview of the structure of the Internet, including descriptions of domains, routing, and proxy service. It then discusses how to connect your Red Hat Linux system to the Internet using PPP dial-up connections. For those who want to connect a LAN to the Internet, it describes how to use Red Hat Linux as a router and set it up to do IP masquerading (to protect your private LAN addresses). Finally, it describes how to configure Red Hat Linux as a proxy server, including how to configure client proxy applications such as Mozilla and Microsoft Internet Explorer.