After activating the config changes, enter the Control Service Panel and select the "network" service from the list.
Services (or daemons) are programs that extend the capabilities of a machine. Daemons start up when the system is booted. Services can be enabled to allow a machine to function as an ftp server, web server, and many others.
Check mandrakeuser.org (external link) for a detailed listing of services that can help you decide which services you may or may not want running on your machine.