Book Image

FreeSWITCH 1.2 - Second Edition

Book Image

FreeSWITCH 1.2 - Second Edition

Overview of this book

FreeSWITCH is an open source telephony platform designed to facilitate the creation of voice and chat-driven products, scaling from a soft-phone to a PBX and even up to an enterprise-class soft-switch. It is always exciting to design and build your own telephony system to suit your needs, but the task is time-consuming and involves a lot of technical skill."FreeSWITCH 1.2" comes to your rescue to help you set up a telephony system quickly and securely using FreeSWITCH. It is rich with practical examples and will give you all of the information and skills needed to implement your own PBX system.You will start with a detailed description of the FreeSWITCH system architecture. Thereafter you will receive step-by-step instructions on how to set up basic and advanced features for your telephony platform.The book begins by introducing the architecture and workings of FreeSWITCH before detailing how to plan a telephone system and then moves on to the installation, configuration, and management of a feature-packed PBX. You will learn about maintaining a user directory, XML dial plan, and advanced dial plan concepts, call routing, and the extremely powerful Event Socket. You will finally learn about the online community and history of FreeSWITCH."FreeSWITCH 1.2" is an indispensable tool for novice and expert alike.
Table of Contents (24 chapters)
FreeSWITCH 1.2
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Regular expressions


The FreeSWITCH XML Dialplan makes extensive use of Perl-compatible regular expressions (PCRE). A regular expression is a means of executing a true/false test on a string of characters. This is commonly called pattern matching. When a regular expression is applied to a string of characters, we answer a simple question: does it match the pattern? If the answer is yes, then usually it means that a particular condition is met, and therefore, the extension in question can be executed. In some cases, we want to do something if a pattern is not met (see the Actions and anti-actions section of this chapter.)

Perl-compatible regular expressions follow a very specific syntax. It can be overwhelming at first. However, once you learn the basics you will appreciate just how powerful they are. The following are some sample regular expressions and their meanings:

Pattern

Meaning

123

Match any string containing the sequence "123"

^123

Match any string beginning with the sequence...