What can Asterisk do for me?

we currently have a switchboard with approx 12 extensions, connected to 2xISDN2 (4 voice channels).

If we were to replace this with Asterisk, what hardware would we require & what are the main benefits of it, over our current switchboard (I think it’s an old Mitel).

This is a wide-open question, you are best off having a look at the link to the O’Reilly book in my signature below. Good luck!

Also, Digium makes hardware that could replace your ISDN setup with the Mitel coupled with Asterisk:

digium.com/index.php?menu=pr … y=hardware

The question is not what asterisk can do for you, but what can you do for asterisk.