I have successfully installed FreePBX on Debian by following this tutorial here http://wiki.freepbx.org/display/HTGS/Installing+FreePBX+on+Debian+Wheezy
but having great difficulty in configuring the server and know it's due to my lack of knowledge in the basics of telephony networking. I have a copy of Asterisk The Definitive Guide
and have read the first 5 chapters but the information seems to be over my head. Can you please help provide some guidance on some basic resources I should look at before diving back into the Asterisk guide?
My aim at this time is to just perform a simple test and understand the basics of how telephony networking works.