Description:

Asterisk is an Open Source PBX and telephony development platform that
can both replace a conventional PBX and act as a platform for developing
custom telephony applications for delivering dynamic content over a
telephone similarly to how one can deliver dynamic content through a
web browser using CGI and a web server.

Asterisk talks to a variety of telephony hardware including BRI, PRI,
POTS, and IP telephony clients using the Inter-Asterisk eXchange
protocol (e.g. gnophone or miniphone). For more information and a
current list of supported hardware, see www.asterisk.org.

BRI support was added from the bri-stuff tarball by Klaus-Peter
Junghanns: http://www.junghanns.net/