Asterisk

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Asterisk

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The Future of Telephony

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Asterisk
The Future of Telephony

™

Jim Van Meggelen, Jared Smith, and Leif Madsen

Beijing • Cambridge • Farnham • Köln • Paris • Sebastopol • Taipei • Tokyo

,COPYRIGHT.10030Page iv Tuesday, August 30, 2005 9:06 AM

Asterisk™: The Future of Telephony
by Jim Van Meggelen, Jared Smith, and Leif Madsen
Copyright © 2005 O’Reilly Media, Inc. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotionaluse. Online editions are also available for most titles (safari.oreilly.com). For more information, contact our corporate/institutional sales department: (800) 998-9938 or corporate@oreilly.com.

Editor: Production Editor: Cover Designer: Interior Designer: Printing History:
September 2005:

Mike Loukides Colleen Gorman Ellie Volckhausen David Futato

First Edition.

Nutshell Handbook, theNutshell Handbook logo, and the O’Reilly logo are registered trademarks of O’Reilly Media, Inc. Asterisk™: The Future of Telephony, the image of starfish, and related trade dress are trademarks of O’Reilly Media, Inc. Asterisk™ is a trademark of Digium, Inc. Asterisk: The Future of Telephony is published under the Creative Commons “Commons Deed” license(http://creativecommons.org/licenses/by-nc-nd/2.0/ca/). Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O’Reilly Media, Inc. was aware of a trademark claim, the designations have been printed in caps or initial caps. While every precaution has been taken in the preparation of this book, the publisher and authors assume noresponsibility for errors or omissions, or for damages resulting from the use of the information contained herein.

This book uses RepKover™ a durable and flexible lay-flat binding. , ISBN: 0-596-00962-3 [M]

,foreword.10522 Page ix Tuesday, August 30, 2005 9:09 AM

Foreword

Once upon a time, there was a boy. ...with a computer ...and a phone. This simple beginning begat much trouble! Itwasn’t that long ago that telecommunications, both voice and data, as well as software, were all proprietary products and services, controlled by one select club of companies that created the technologies, and another select club of companies who used the products to provide services. By the late 1990s, data telecommunications had been opened by the expansion of the Internet. Prices plummeted....