Building Embedded Linux Systems

Chapter 10. Setting Up Networking Services

Increasingly, embedded system designers are called upon to include networking capabilities in their products. An embedded system may, for example, include a web server to enable web-based configuration. It may also enable remote login for maintenance and upgrading purposes. Because the Linux kernel, and the networking software that run on it, are often the preferred software for running networking services that require high reliability and high availability, you will find Linux particularly well suited for networking applications.

In this chapter, we will discuss the setup and configuration of the networking services most commonly found in embedded Linux systems. This discussion will include instructions on how to cross-compile each networking package and how to modify the target’s root filesystem to run the services provided by each package. In particular, I will cover the use of the internet super-server (inetd), remote administration with SNMP, network login through Telnet, secure communications with SSH, serving web content through HTTP, and dynamic configuration through DHCP.

There are, of course, many other networking services that can run on top of Linux. Though I couldn’t realistically cover all of them in a single chapter, the explanations included here should provide you with some hints as to how to install and use other networking packages. Also, I will not cover the setup, configuration, and use of actual networking hardware. ...