FreePBX is used as the face of Asterisk servers so much that it tends to be taken for granted. But it is more than a pretty, pointy-clicky interface to Asteriskit is "a sophisticated PBX Framework that transforms a LAMPA System (Linux, Apache, MySQL, PHP, Asterisk) into a world class PBX."
FreePBX began life as AMP, the Asterisk Management Portal. Most users were introduced to it through Asterisk@Home, which evolved into trixbox, and which still uses FreePBX. FreePBX has matured a lot since its AMP days. Asterisk is an extremely complex beast, so we must be grateful to those foolishI mean brave, determined souls who design graphical management interfaces for it. The easy way to try out FreePBX is to install a free, prefab Asterisk bundle that includes FreePBX, such as PBX in a Flash or trixbox CE. If you're into spending some money, visit the FreePBX store for a variety of bundles that include hardware. You may also install it separately on top of your own Asterisk installation, though this takes a bit more work as you'll have to install it from source code.
So what do you get after all this toil? You get a modular, customizable Web-based graphical interface for both system administrators and users. The current stable release, the 2.3 series, supports both Asterisk 1.2 and 1.4. The 2.4 release, which is in beta, will also support those, plus Asterisk's upcoming 1.6 release. (No, it's not here yet, FreePBX is planning for the future.)
My two favorite features are graceful upgrades, and the module manager. Every new release includes an upgrade script. It preserves all of your settings and puts everything in its proper place, and you can upgrade it on a running system for no downtime. The module manager is a painless way to add modules to get additional functionalityor to remove them.
Recording and reviewing custom voice prompts, and setting up IVRs (Interactive Voice Response) is easy, as is scheduling various voice prompts for different times of day and days of the week. Conferencing, ring groups, extensions, follow-me, and users are all pretty easy to manage. There is a status page that shows system statistics, such as CPU and memory usageas well as available disk space, call data, and server status. Setting up trunks and connecting to service providers is not bad at all. Entering the relevant information for these tasks is definitely easier on a single Web form than chasing down all the relevant configuration files.
FreePBX is task oriented and may write to several different Asterisk configuration files in carrying out a single task. So if you want to tweak Asterisk configuration files directly, you're going to have to know which ones and what to do with them.
Becoming an iPBX mogul
FreePBX and Asterisk are popular with users who want to build businesses around them, or add them to an existing line of services. FreePBX is licensed under GPL2, so anyone with PHP skills can customize and modify it, or at least put their own branding on it. In fact you could build your entire stack on open source, free-of-cost software: the operating system, Asterisk, backend databases, HTTP servers, network and system administration utilities, FreePBX, the works. Anyone who does go this route should make a point of supporting the great projects that make this possibleslip them some cash, contribute patches and bug reports, write some documentation, give them public credit. Don't just be a leech.
So what sort of people are doing this? It's quite a mix, from Asterisk hobbyists who turn it into a business, to foresightful IT companies anticipating the changing climate, to various service providers who have to choose between watching their customers evaporate, or stepping up into the 21st century and offering them more.
It's a good idea to hone both your technical and social skills before launching yourself forth into a new venture. There is all kinds of technical training out there. Yes, it costs money, what do you expect? Everything for free? The fine FreePBX persons are holding a three-day training seminar next month Charleston, South Carolina, February 2729th. Not only does it cover nearly everything you need to know to implement iPBX systems, it also includes some marketing and business coaching.
The FreePBX folks have a lot of good stuff in the pipeline for future releases: Hylafax integration, a central registry to warn of duplicate extension numbers, and even a DUNDI registry to coordinate extension numbers across multiple sitesand of course many other improvements, refinements, and new features.