This book shows how to build a telephony system for your home or business using the free and open source application, Asterisk. 'Building a Telephony System with Asterisk' takes you step-by-step through the process of installing and configuring Asterisk. It shows you how to make a deployment plan, and how to create a dial plan. The book also presents example configurations for using Asterisk in three different scenarios: for small and home offices, small businesses, and Hosted PBX.With an engaging style and excellent way of presenting information, this book makes a complicated subject very easy to understand. This book is aimed at anyone who is interested in building a powerful telephony system using the free and open source application, Asterisk, without spending many thousands of dollars buying a commercial and often less flexible system. This book is suitable for the novice and those new to Asterisk and telephony. Telephony or Linux experience will be helpful, but not required.