Overview

Secrets in This Chapter

• Understanding IP Addresses

• Getting IP Addresses for Your Network

• Using Supernets or CIDR

• Learning about IPv6

• Routing TCP/IP Packets

• Understanding the Domain Name System (DNS)

• Performing Client/Server Communications with TCP/IP

• Learning How xinetd Works

• Understanding the xinetd Configuration Files

• Starting Standalone Servers

• Configuring Networks at Boot Time

UNIX and networking go hand in hand; TCP/IP (Transmission Control Protocol/ Internet Protocol) networking is practically synonymous with UNIX. As a UNIX clone, Linux includes extensive built-in networking capabilities. In particular, Linux supports TCP/IP networking over several physical interfaces, such as Ethernet cards, serial ports, and parallel ports.

Typically, you use an Ethernet network for your local area network (LAN)—at your office or even your home (if you happen to have several systems at home). TCP/IP networking over the serial port enables you to connect to other networks by dialing out over a modem. Linux supports both Serial Line Internet Protocol (SLIP) and Point-to-Point Protocol (PPP).

This chapter focuses on Linux’s support for Ethernet and TCP/IP. The chapter starts with a discussion of networking in general and TCP/IP in particular, then it covers the physical setup of an Ethernet LAN, including information about specific brands of Ethernet cards. Finally, the chapter describes how to set up a TCP/IP network on a Linux system.