Introduction: Installing the Old Trixbox 2.2
Trixbox is now at version 2.8, but you can get some of the terminology from the video which is useful. The current version is available from http://fonality.com/trixbox/. This is a computer based phone system aka pbx and or a voip system. I will have a follow up instructable with more details. To my knowledge, I have no financial ties with this company.
Trixbox 2.8 install in espanol: http://www.youtube.com/watch?v=mLeFp91eUE4 Caveat emptor.
A second instructible is coming about Trixbox. (in progress).