If you are a new at VoIP look into these publications:<br><a href="http://www.amazon.com/SIP-Understanding-Initiation-Protocol-Telecommunications/dp/1607839954/ref=sr_1_1?ie=UTF8&s=books&qid=1272415143&sr=1-1">http://www.amazon.com/SIP-Understanding-Initiation-Protocol-Telecommunications/dp/1607839954/ref=sr_1_1?ie=UTF8&s=books&qid=1272415143&sr=1-1</a><br>
<br><a href="http://www.amazon.com/SIP-Beyond-VoIP-Communications-Revolution/dp/0974813001/ref=sr_1_10?ie=UTF8&s=books&qid=1272415143&sr=1-10">http://www.amazon.com/SIP-Beyond-VoIP-Communications-Revolution/dp/0974813001/ref=sr_1_10?ie=UTF8&s=books&qid=1272415143&sr=1-10</a><br>
<br><a href="http://www.amazon.com/Building-Telephony-Systems-OpenSIPS-1-6/dp/1849510741/ref=sr_1_12/189-7099384-6630443?ie=UTF8&s=books&qid=1272415088&sr=1-12">http://www.amazon.com/Building-Telephony-Systems-OpenSIPS-1-6/dp/1849510741/ref=sr_1_12/189-7099384-6630443?ie=UTF8&s=books&qid=1272415088&sr=1-12</a><br>
<br><a href="http://www.amazon.com/Understanding-Servlets-Artech-House-Telecommunications/dp/159693428X/ref=sr_1_9?ie=UTF8&s=books&qid=1272415143&sr=1-9">http://www.amazon.com/Understanding-Servlets-Artech-House-Telecommunications/dp/159693428X/ref=sr_1_9?ie=UTF8&s=books&qid=1272415143&sr=1-9</a><br>
<br><a href="http://www.amazon.com/Switching-VoIP-Theodore-Wallingford/dp/0596008686/ref=sr_1_1?ie=UTF8&s=books&qid=1272415530&sr=1-1">http://www.amazon.com/Switching-VoIP-Theodore-Wallingford/dp/0596008686/ref=sr_1_1?ie=UTF8&s=books&qid=1272415530&sr=1-1</a><br>
<br>Or look into these Google eBooks links<br><a href="http://books.google.com/books?id=9_wRFy5OGw4C&dq=asterisk+book&printsec=frontcover&source=bn&hl=en&ei=mYXXS6DeG4bc8ASul_SSBw&sa=X&oi=book_result&ct=result&resnum=4&ved=0CCsQ6AEwAw#v=onepage&q=asterisk%20book&f=false">http://books.google.com/books?id=9_wRFy5OGw4C&dq=asterisk+book&printsec=frontcover&source=bn&hl=en&ei=mYXXS6DeG4bc8ASul_SSBw&sa=X&oi=book_result&ct=result&resnum=4&ved=0CCsQ6AEwAw#v=onepage&q=asterisk%20book&f=false</a><br>
<br>-E<br clear="all"><br>