How to build a voip system from group zero

I am working on a research project to develop a VOIP system. Basica functionality includes allowing landline to call another landline via VOIP, preferably through a web interface, similar to JaJah. I am a newbie in this area and would appreciate any help in guiding me on how to implement such kind of system step-by-step.

Thank you very much in advance for all your kind help.


I would recommend reading: “Asterisk: The Future of Telephony”.