GOautodial is an
open source web based software on which you can build a phone system for
your call center. It enables open source predictive dialer and inbound
IVR + Automated Call Distribution system.
trixbox is an open telephony platform utilizing the best of the open
source telephony tools into one easy-to-install package. Based on an
enhanced LAAMP (Linux, Apache, Asterisk, mySQL, PHP) the trixbox
dashboard provides easy to use web-based interfaces to setup, manage,
maintain, and support an complete IP PBX system.