Trixbox is designed around the CentOS distribution of Linux. CentOS is built from the Red Hat Enterprise source packages. It has a relatively small core team of developers that concentrate on packaging the OS without Red Hat's proprietary components. The main focus of CentOS is to provide a freely available operating system with the packages and features needed at enterprise level, without the cost associated with the base distribution—Red Hat Enterprise Linux. However, CentOS does offer a range of commercial support, which is invaluable to most enterprises and thus is an option we can consider.
CentOS isn't the focus of this chapter and it doesn't really have too much bearing on our use of Trixbox other than knowing basically how to use and update it. We will focus on the setup and maintenance of Trixbox and the features it provides for us. If we decide to use Trixbox, it would be beneficial to spend time getting to know CentOS.