We needed a network analysis tool and decided to use ntop. Official ntop website provides binary packages for Ubuntu and CentOS.
Ubuntu has an official package for ntop but the package is version 3 and we preferred to use the latest version, so package repositories were no good for us.
We set up a CentOS 6 server and installed ntop rpm package. But the package did not include an init script. Here is an init script to start/stop ntop in CentOS: