inetd = Internet Super daemon

Provides smarts for network daemons that are otherwise limited in their ability to manage network 
connection such as: chargen, finger, echo, etc.

When inetd runs it reads inetd.conf, to determine which network services it is responsible for, 
and /etc/services to determine which ports it should listen on.

When a connection request comes in on one of these ports, 
inetd acts as a broker, and starts up the required daemon 
(as set out in inetd.conf).  




init is responsible for starting up the services in /etc/rc.d/rc<*>.d 
(as dictated by /etc/inittab's default run level, but only  
after init runs /etc/rc.sysinit)

All the services in /etc/rc.d/rc<*>.d are symbolic links to files in /etc/rc.d/init.d

Such services include portmapper, sendmail, httpd, named.

So why use init instead of inetd?

1. Some network daemons require the use of a super network daemon to help them manage network connections 
   (suc has mulitple connections)

2. if TCP_Wrappers are required, and it is not possible to build in lib_wrap, then run out of inetd.conf

3. if the network daemon is resource intensive each time it starts (i.e. httpd, shh -- generating keys) then
   init probably better.

4.  standalone daemons more suited for init

5.  inetd being slowly replaced by xinetd

6.