xinetd, the eXtended InterNET Daemon, is an open-source daemon which runs on many Linux and Unix systems and manages Internet-based connectivity.
xinetd, the eXtended InterNET Daemon, is an open-source daemon which runs on many Linux and Unix systems and manages Internet-based connectivity. It offers a more secure extension to or version of inetd, the Internet daemon.
xinetd performs the same function as inetd: it starts programs that provide Internet services. Instead of having such servers started at system initialization time, and be dormant until a connection request arrives, xinetd is he only daemon process started and it listens on all service ports for the services listed in its configuration file. When a request comes in, xinetd starts the appropriate server. Because of the way it operates, xinetd (as well as inetd) is also referred to as a super-server.
Source:nixCraft