The FreeSWITCH™ dialplan is a decision tree that provides routing services to bridge call legs together, execute dialplan applications, and invoke custom scripts that you write, among other things. Much of your effort will be focused on configuring a dialplan to suit your application, whether it is the built–in XML dialplan or a database lookup query sent to a web server via xmlcurl or via PostgreSQL using freeswitch.dbh connection pooling.
The FreeSWITCH™ Dialplan is not a single entity. You have the option to run different dialplan subsystems natively. These are not all translated into the same back–end as other systems may be employed. Instead each is a unique, independent method through which you can access information.
Unlike some other switches, the dialplan is not designed to be an end all be all scripting language that you put a bunch of logic into. The dialplan, quite simply is designed to take a call request, decide where it should forward to and forward to an application. For example, you can route a call to the bridge application, and that application will spawn a new channel, and then connect the two channels; it can route to the conference application, or any other registered application in the FreeSWITCH™ system. Some of the most common applications you might want to use, such as mod_dptools: bridge, can be found in the documentation of the dptools module.
The design to allow for multiple dialplan processing modules as well as routing calls to applications which do all the hard work gives you the flexibility to do what you need the way that you need it to work. It does not force you to adapt your infrastructure around FreeSWITCH™ but lets FreeSWITCH™ more readily mesh with your existing infrastructure.
FreeSWITCH uses multiple 'contexts' to prevent internal extensions from being exposed to the world. The two contexts in the vanilla FS config are called "Public" and "Default" (but these names are arbitrary and can be carefully changed or other contexts added). Everything in the "public" context is available to the world, while everything in "default" context is only available to users that have registered with FreeSWITCH. You can define in the user profiles (the user directory) which context they belong to, and you can define the public context in the sofia configuration.
- Dialplan XML - XML Dialplan Module (the most common).
- LDAP Directory - LDAP Directory Dialplan Module
- mod_dialplan_asterisk - Asterisk compatible dialplan module.