In the dialplan we can use the ConfBridge() application too start a conference call. There are four parameters we can set within the applications, the Conference Number, Bridge Profile, User Profile, and Conference Menu.

The Conference Number can be any numeric value. If multiple callers are connected with the same Conference Number, they are then joined to the same conference call. The Conference Number is created here in the dialplan and is the first parameter of the ConfBridge() application. It is also the only required parameter of the application.

The Bridge Profile parameter sets which bridge profile the conference call will use. The profiles are setup in the confbridge.conf file. In the last lesson we created the [default_bridge] context. If we do not set this parameter in the ConfBridge() application it will default to using [default_bridge]. Each conference call can have only one Bridge Profile at a time.

Similar to the Bridge Profile, the User Profiles are setup in the confbridge.conf file. If we do not set this parameter in the ConfBridge() application it will default to using [default_user]. There can be multiple User Profiles connecting to the same conference call.

The last parameter is the Conference Menu. It reference a context from the confbridge.conf file and provides a user with DTMF key options. Each user can have their own menu. In the last lesson we added in the [sample_user_menu] that can be used.

Now lets create an extension that can be used to setup a conference call. Using nano open the extensions.conf file:

sudo nano /etc/asterisk/extensions.conf

Add a new extension number to the file that will be used for the conference call. I will use extension 280. Use the ConfBridge() application to create a conference bridge number of your choice. I will use 123. Be sure to add the Bridge Profile, User Profile, and Conference Menu form the last lesson.

exten => 280,1,NoOp(Conference Room 123)
same => n,ConfBridge(123,default_bridge,default_user,sample_user_menu)
same => n,Hangup