The demo configuration

Understanding all of these concepts right off the bat is far from easy, and as maintainers of the software, we do not expect most people to have everything just click. This is the main reason that every new layer we put on top of the core makes things simpler and easier to learn. The demonstration configuration of FreeSWITCH is the last line of defense between new users of the software and all of the crazy, complicated, and sometimes downright evil stuff better known as Real Time Communication. We try very hard to save the users from such things.

The main purpose of the demonstration configuration in FreeSWITCH is to showcase all of the hundreds of parameters there are to work with. We present them to you in a working configuration that you could actually leave untouched and play with before trying your own hand at changing some of its options. Think of FreeSWITCH as a Lego set. FreeSWITCH and all of its little parts are like a brand new bucket Lego bricks, with plenty of parts to build anything we can imagine. The demonstration configuration is like the sample spaceship that you find in the instruction booklet. It contains step-by-step instructions on exactly how to build something you know will work. After you pick up some experience, you might start modifying your Lego ship to have extra features, or rebuild the parts into a car or some other creation. Obviously, you can leave outmany, or most, of the features built in that configuration and use only what is useful in your specific deployment. The good news about FreeSWITCH is that it comes out of the box already assembled. Therefore, unlike the bucket of Lego bricks, if you get frustrated and smash it to bits, you can just re-install the defaults and you won't have to build it again from scratch. The demonstration configuration is discussed in Chapter 3, Test Driving the Example Configuration.

Once FreeSWITCH has been installed, you only need to start its executable without changing one line in the configuration file. You will be immediately able to point a SIP telephone or software-based SIP softphone to the address of your server (be it your laptop, a virtual machine, a 48-core server, a Raspberry Pi, or an Amazon instance), make a test call, and access all of the functionalities of FreeSWITCH. Interfacing with other protocols will require additional configurations (such as installing SSL certificates for WebRTC and the like), but the end results will be exactly the same. If you have more than one phone, using the default configuration you should be able to configure them to each having an individual extension in the range 1000-1019, which is the extension number range that is predefined in the demonstration configuration. Once you get the phones registered, you will be able to make calls across them or have them meet in a conference room in the 3000-3399 range. If you call an extension that is not registered, or let the phone ring on another extension for too long, the voicemail application will use the phrase system to indicate that the party is not available, and ask you to record a message. If you dial 5000, you can see an example of the IVR system at work, presenting several menu choices demonstrating various other neat things FreeSWITCH can do. There are a lot of small changes and additions that can be made to the demonstration configuration while still leaving it intact.

For example, using the pre-processor directives we went over earlier, the demonstration configuration loads a list of files into the XML registry from certain places, meaning that every file in a particular folder will be combined into the final XML configuration document. The two most important points where this takes place are where the user accounts and the extensions in the Dialplan are kept. Each of the 20 extensions that are preconfigured with the defaults are stored into their own file. We could easily create a new file with a single user definition, drop it into place to add another user, and issue the reloadxml command at the FreeSWITCH CLI. The same idea applies to the example Dialplan. We can put a single extension into its own file and load it into place whenever we want.