... 67References, 676 VoIP Deployment in Enterprises 6 8IP- Based Endpoints: Desktop and Conference Phones, 6 9IP- PBX, IP Centrex, and IP- Based PBX Tie Lines, 7 1IP- VPN and VoIP for Tele-Workers, 77Web-Based Call ... format.Library of Congress Cataloging-in-Publication Data is available.ISBN 0-4 7 1-2 166 6-6 Printed in the United States of America10987654321 IMPLEMENTING VOICEOVER IPBHUMIP KHASNABISHLexington, Massachusetts, ... long-distance(both national and international, CLASS-3, -2 , and -1 ) transmission of thevoice signal as well. Figure 1-2 shows an implementation of long-distance voicetransmission using the IP...