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This edition takes the beginner by the hand and leads them through not only getting a simple dial plan working but in showing the steps to network several servers together.

For the experienced, you can skip around and just read the parts where you need a refresher but for the newbie, this book is indispensable.

This is the recommended text for the Digium boot camps and a mastery of this book will make it possible to get the Digium Certified Asterisk Professional Certificate.

I convinced the computer science department to offer an introduction to VoIP class at the local community college and this is the recommended text for that class.