Switching to VoIP

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Preface

Conventions

Most definitions are given upon first encountering a new term. There’s a glossary

included in case you miss a definition or just need a refresher.

Carrier is a word that is referred to in many different ways throughout the book.

Sometimes it means a phone company, other times it refers to a data link system.

Wherever a word has two potential meanings, the context should tell you which

meaning is appropriate.

In most cases, examples are provided in terms of North American standards and

practices. Where appropriate, European or Asian equivalents are mentioned.

Kilobit is abbreviated as k, while kilobits per second shows up as kbps. The same

convention is used for mega- and giga- prefixes where applicable. For the sake of

clarity, many authors will define whether kilo means 1,000 or 1,024. This is an

important distinction, but you don’t need to worry much about it here. It’s safe to

assume a multiple of 1,000 when kilo is used. That is, 64 kilobits is exactly 64,000

bits and so on.

The following typographical conventions are used in this book:

Plain text

Indicates menu titles, menu options, menu buttons, and keyboard accelerators

(such as Alt and Ctrl).

Italic

Indicates new or technical terms, system calls, URLs, hostnames, email

addresses, filenames, file extensions, ...