[...]... is why documentation 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 successful that it is no longer... because of the ease with which a novice can understand basic concepts Then it continues to succeed as the novice becomes a pro and starts tapping the “other ways to do it” with more sophisticated implementations, using AGI with Java, Perl, or Python (or one of the other dozen or so supported languages), or even writing her own custom apps that work as compile-time options in Asterisk But the first step... physical interface types The creation and growth of Asterisk were the inescapable results of the convergence of the four horsemen of the proprietary hardware apocalypse: open source development ideas, the Internet, Moore’s Law, and the plummeting costs of telecommunications Even hardware vendors who may be frightened of Asterisk from a competitive standpoint are using it in their labs and core networks:... 6, Dialplan Basics Introduces the heart of Asterisk, the dialplan Chapter 7, Outside Connectivity Discusses how to configure Asterisk to connect to other systems, such as other Asterisk servers, Internet telephony service providers, or the plain old telephone network Chapter 8, Voicemail Covers the usage of one of the most popular applications included with Asterisk, the voicemail system Chapter 9,... stimulating new thoughts, and for pushing the envelope Everyone in the Asterisk community also needs to thank Jim Dixon for creating the first open source telephony hardware interfaces, starting the revolution, and giving his creations to the community at large * We tried wherever possible to include the contributors’ names, but in some cases could not, and therefore included their handles instead † Without... project, largely due to the pleasure of working with the two of you Thanks for the laughs and for your dedication to this book as a team effort I have learned a lot from many people at Digium There are three people who stand out the most as my mentors: Mark Spencer, Kevin P Fleming, and David Deaton Thank you all for going the extra mile to teach me along the way I am extremely grateful To the software development... 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 xxiii Organization The book is organized into these chapters: Chapter 1, A Telephony Revolution This is where we chop up the kindling and light the fire Welcome to Asterisk!... Dialplan Using Arguments in Macros GoSub() Defining Subroutines Calling Subroutines from the Dialplan Using Arguments in Subroutines Returning from a Subroutine Local Channels Using the Asterisk Database (AstDB) Storing Data in the AstDB Retrieving Data from the AstDB Deleting Data from the AstDB Using the AstDB in the Dialplan Handy Asterisk Features Zapateller() Call Parking Conferencing with MeetMe()... best Also thanks to Teresa Elsey, our production editor, and the rest of the unsung heroes in O’Reilly’s production department These are the folks that take our book and make it an O’Reilly book During the course of writing this book, we had the pleasure of being able to consult with many people with specific experience in various areas Their generous contributions of time and expertise were instrumental... calls to the participants? No problem Integration of voice services into existing Java apps? Easy Fax? Instant messages? IVRs? Video? Yes, yes, yes, yes The affirmative answers just keep flowing, and at that point, the best thing to do is to sit the person down and start showing him quick demonstrations of how Asterisk can be quickly deployed and developed Then, I typically point the person toward the first . alt="" Asterisk™: The Definitive Guide Downloa d f r o m W o w ! e B o o k < w w w.woweb o o k . c o m > THIRD EDITION Asterisk™: The Definitive Guide Leif. Handbook, the Nutshell Handbook logo, and the O’Reilly logo are registered trademarks of O’Reilly Media, Inc. Asterisk: The Definitive Guide, the images