I’ve been looking all over the place and I can’t find a simple list of the functionalities that Asterisk provides. Can anybody help ?
i think the Digium website looks and navigates like a dogs dinner ! it used to be so much easier to use.
asterisk.org/support/features should be of use to you.
A short answer to your question might be that asterisk is a software system that will allow you to automatically process your phone calls. If you have modem cards, it will communicate directly with your phone company. If you have access to the Internet, you can communicate directly with Internet phone companies. To use conventional analog telephones with your asterisk system, you will need either a special modem card or a SIP telephone adapter.
Asterisk will manage incoming calls through dialplans that you create. Dialplans can be very simple (send to voicemail) or more complicated (i.e., if you are using a call attendant). Dialplans are also used for outgoing calls (so you have the option to route calls to different lines).
Asterisk comes with a range of features available to you: voicemail, meeting rooms, call recording, call detail recording, call queues (I have not used this feature yet). Asterisk dialplans allow you to pass control to external applications (written in perl, php, or the language of your choice) so that you have the flexibility to extend these capabilities for custom applications (I use these extensions to “announce” incoming calls through my soundcard with the name of the incoming caller before the phone rings.
This is a short response, you may want to check the online documentation, specifically “Asterisk, The future of Telephony” if you want additional details.