Page 37 - Asterisk™: The Future of Telephony

What this means, in part, is that the true value of a technology is often not known until
it has been deployed.
How compelling, then, to have a system that holds at its very heart the concept of
openness and the value of continuous innovation.

This Book

So where to begin? Well, when it comes to Asterisk, there is far more to talk about than
we can fit into one book. For now, we’re not going to take you down all the roads that
the über-geeks follow—we’re just going to give you the basics.
In Chapter 2, we cover some of the engineering considerations you should keep in mind
when designing a telecommunications system. You can skip much of this material if
you want to get right to installing, but these are important concepts to understand,
should you ever plan on putting an Asterisk system into production.

Chapter 3 covers obtaining, compiling, and installing Asterisk, and Chapter 4 deals
with the initial configuration of Asterisk. Here we cover the important configuration
files that must exist to define the channels and features available to your system. This
will prepare you for Chapter 5, where we introduce the heart of Asterisk—the dialplan.
Chapter 6 will introduce some more advanced dialplan concepts.
We will take a break from Asterisk in Chapter 7 and discuss some of the more important
technologies in use in the PSTN. Naturally, following the discussion of legacy
telephony, Chapter 8 discusses Voice over IP.
Chapter 9 introduces one of the more amazing components, the Asterisk Gateway
Interface (AGI). Using Perl, PHP, and Python, we demonstrate how external programs
can be used to add nearly limitless functionality to your PBX. In Chapter 14, we briefly
cover what is, in fact, a rich and varied cornucopia of incredible features and functions,
all of which are part of the Asterisk phenomenon. To conclude, Chapter 15 looks for-
ward, predicting a future where open source telephony completely transforms an
industry desperately in need of a revolution. You’ll also find a wealth of reference in-
formation in the book’s five appendixes.
This book can only lay down the basics, but from this foundation you will be able to
come to an understanding of the concept of Asterisk—and from that, who knows what
you will build?

This Book | 9