System information

Preface
This is a book for anyone who uses Asterisk.
Asterisk is an open source, converged telephony platform, which is designed primarily
to run on Linux. Asterisk combines more than 100 years of telephony knowledge into
a robust suite of tightly integrated telecommunications applications. The power of
Asterisk lies in its customizable nature, complemented by unmatched standards com-
pliance. No other PBX can be deployed in so many creative ways.
Applications such as voicemail, hosted conferencing, call queuing and agents, music
on hold, and call parking are all standard features built right into the software. More-
over, Asterisk can integrate with other business technologies in ways that closed, pro-
prietary PBXs can scarcely dream of.
Asterisk can appear quite daunting and complex to a new user, which is why docu-
mentation is so important to its growth. Documentation lowers the barrier to entry and
helps people contemplate the possibilities.
Produced with the generous support of O’Reilly Media, Asterisk: The Definitive
Guide is the third edition of what was formerly called Asterisk: The Future of
Telephony. We decided to change the name because Asterisk has been so wildly suc-
cessful that it is no longer an up-and-coming technology. Asterisk has arrived.
This book was written for, and by, members of the Asterisk community.
Audience
This book is intended to be gentle toward those new to Asterisk, but we assume that
you’re familiar with basic Linux administration, networking, and other IT disciplines.
If not, we encourage you to explore the vast and wonderful library of books that
O’Reilly publishes on these subjects. We also assume you’re fairly new to telecommu-
nications (both traditional switched telephony and the new world of Voice over IP).
However, this book will also be useful for the more experienced Asterisk administrator.
We ourselves use the book as a reference for features that we haven’t used for a while.
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