What configuration is required for call conferencing in asterisk 13 version

what configuration is required for call conferencing in asterisk 13 version
I write dial plan for conferencing ,Is any other setting required for conferencing??

Not mandatory but would be helpul check the file confbridge.conf for any customization

You’ll also want to check that app_confbridge.so is loaded. I still use MeetMe for conferencing, but it requires DAHDI.

meetme requires dahdi, confbridge does not. Confbridge is the recommended conference app.