Avaya 4600 Series Service manual

4600 Series IP Telephone
LAN Administrator’s Guide
555-233-507
Comcode 700197841
Issue 1.5
June 2001

Copyright and Legal Notices
Notice Every effort was made to ensure that the information in this document was complete and accurate at the time of
printing. However, information is subject to change.
Intellectual Property Intellectual property related to this product (including trademarks) and registered to Lucent Technologies Inc.
has been transferred or licensed to Avaya Inc.
Any reference within the text to Lucent Technologies Inc. or Lucent should be interpreted as reference to Avaya
Inc. The exception is cross references to books published prior to April 1, 2001, which may retain their original
Lucent titles.
Avaya, formed as a result of Lucent's planned restructuring, designs, builds, and delivers voice, converged
voice and data, customer-relationship management, messaging, multiservice networking, and structured
cabling products and services. Avaya Labs is the research and development arm for the company.
Your Responsibility for
Your System's Security Toll fraud is the unauthorized use of your telecommunications system by an unauthorized party, for example,
persons other than your company’s employees, agents, subcontractors, or persons working on your company’s
behalf. Note that there may be a risk of toll fraud associated with your telecommunications system and, if toll
fraud occurs, it can result in substantial additional charges for your telecommunications services.
You and your system manager are responsible for the security of your system, such as programming and
configuring your equipment to prevent unauthorized use. The system manager is also responsible for reading
all installation, instruction, and system administration documents provided with this product in order to fully
understand the features that can introduce risk of toll fraud and the steps that can be taken to reduce that risk.
Avaya does not warrant that this product is immune from or will prevent unauthorized use of common-carrier
telecommunication services or facilities accessed through or connected to it. Avaya will not be responsible for
any charges that result from such unauthorized use.
Trademarks Adobe, Acrobat, and the Acrobat logo are registered trademarks of Adobe Systems Incorporated.
DOS, Microsoft, Notepad, Windows, Windows NT, and the Microsoft logotype are registered trademarks and
Windows for Workgroups and Windows 95 are trademarks of the Microsoft Corp.
DEFINITY and the Avaya logotype are registered trademarks of Avaya.
All products and company names are trademarks or registered trademarks of their respective holders.
Comments If you have comments, complete and return the comment card at the end of this document.
Copyright 2001,
Avaya Inc.
All Rights Reserved
Printed in U.S.A.
555-233-507
Comcode 700197841
Issue 1.5
June 2001

4600 Series IP Telephone LAN Administrator’s Guide
Master Table of Contents
Master TOC i
1 Introduction
About This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Intended Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Document Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
■Change History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
■Terms Used in This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
■Conventions Used in This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Online Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Customer Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
2 Overview of Voice over IP (VoIP)
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Overview of Voice over IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
■Data and Voice Network Similarities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
■Delay and Jitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■Tandem Coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■Voice Coding Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■H.323 Standard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■TFTP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■NAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■QoS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
SNMP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Network Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Suggestions for Installation and Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
■Reliability and Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
■Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
4600 Series IP Telephones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Dual Connection Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Registration and Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6

4600 Series IP Telephone LAN Administrator’s Guide
ii Master TOC
■WAN Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■DHCP and DEFINITY Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
Initialization Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
■Step 1: Telephone to Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 2: DHCP Server to Telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 3: Telephone and TFTP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 4: Telephone and the DEFINITY Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8
3 Requirements
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
■Software Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
4 Server Administration
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Administering 4600 Series IP Telephones on
DEFINITY Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
■DEFINITY Release 8.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
■DEFINITY Release 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
DHCP and TFTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Software Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Required Network Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
DHCP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
■Choosing a DHCP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
■DHCP Software Alternatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
■Generic Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
■Windows NT 4.0 DHCP Server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5
■Windows 2000 DHCP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-9
TFTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13
■Generic Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13
■Avaya TFTP (Suite Pro) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14
4600 Series IP Telephone Scripts and Application Files . . . . . . . . . . . . . . . . . . . . . .4-14
■Contents of the Upgrade Script . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16
QoS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16
■IEEE 802.1D and 802.1Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16
■DIFFSERV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-17
■UDP Port Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Administering Options for the 4600 Series IP Telephones . . . . . . . . . . . . . . . . . . . .4-18
■Customizing the Site-Specific Option Number (SSON) . . . . . . . . . . . . . . . . . . . . .4-20
■Customizing the Script File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20

Master Table of Contents
Master TOC iii
■Entering Options via the Telephone Dialpad . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-21
■Customizing the Upgrade Script File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-21
5 Troubleshooting Guidelines
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
The View Administrative Option. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5
Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
A Appendix
Avaya - 46xx IP Telephone MIB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-1

4600 Series IP Telephone LAN Administrator’s Guide
iv Master TOC

Contents
1-i
1
Introduction
About This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Intended Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Document Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
■Change History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
■Terms Used in This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
■Conventions Used in This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Online Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Customer Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7

4600 IP Telephone LAN Administrator’s Guide
1-ii

About This Guide
1-1
1
Introduction 1
Program
About This Guide 1
This guide provides a description of Voice over IP, describes how to administer the DHCP and
TFTP servers; and how to troubleshoot operational problems with the 4600 Series IP Telephones
and the servers.
The 4600 Series IP Telephone product line is a supplement to the DEFINITY IP Solutions platform.
Intended Audience 1
This document is intended for personnel administering the DHCP and TFTP servers to support the
4600 Series IP Telephones.
CAUTION:
Many of the products mentioned in this document are not supported by Avaya. Care should
be taken to ensure there is adequate technical support available for the TFTP and DHCP
servers. If the TFTP or DHCP servers are not functioning correctly, the 4600 Series IP
Telephones may be unable to operate correctly.
Document Organization 1
The guide contains the following sections:
Chapter 1, ‘‘Introduction’’ Provides an overview of the 4600 Series IP Telephone
Administrator’s document.
Chapter 2, ‘‘Overview of Voice
over IP (VoIP)’’ Describes VoIP and factors influencing its performance that must be considered when implementing this feature.
Chapter 3, ‘‘Requirements’’ Describes the hardware and software requirements for Avaya’s
VoIP offering.

4600 Series IP Telephone LAN Administrator’s Guide
Document Organization
1-2
Change History 1
Terms Used in This Guide 1
Chapter 4, ‘‘Server
Administration’’ Describes the administration of DHCP and TFTP for the 4600 Series IP Telephones.
Chapter 5, ‘‘Troubleshooting
Guidelines’’ Describes messages that may occur during the operation of the 4600 Series IP Telephones.
Appendix A, ‘‘Avaya - 46xx IP
Telephone MIB’’ Provides the MIB specification for the 46xx IP Telephones (4600, 4612, and 4624).
Issue 1.0 This document was issued for the first time in November 2000.
Issue 1.1 This is the current version of the document, revised and issued
in April 2001.
802.1p
802.1Q
802.1Q defines a layer 2 frame structure that supports VLAN
identification and a QoS mechanism usually referred to as
802.1p, but the content of 802.1p is now incorporated in 802.1D.
ARP Address Resolution Protocol, used to verify that the IP address
provided by the DHCP server is not in use by another IP
Telephone.
CELP Code-excited linear-predictive; voice compression requiring only
16 kbps of bandwidth
CLAN Control LAN, type of TN799 circuit pack
DHCP Dynamic Host Configuration Protocol, an IETF protocol used to
automate IP Address allocation and management.
DiffServ Differentiated Services, an IP-based QoS mechanism.
IETF Internet Engineering Task Force, the organization that produces
standards for communications on the internet.
LAN Local Area Network.
MAC Media Access Control, ID of an endpoint.
NAT Network Address Translator.
PSTN Public Switched Telephone Network, the network used for
traditional telephony
QoS Quality of Service, used to refer to a number of mechanisms
intended to improve audio quality over packet-based networks.
RRQ Read Request packet, a message sent from the 4600 Series IP
Telephone to the TFTP server, requesting to download the
upgrade script and the application file.

Introduction
Document Organization
1-3
Conventions Used in This Guide 1
This guide uses the following textual, symbolic, and typographic conventions to help you interpret
information.
Symbolic Conventions 1
CAUTION:
This symbol is used to emphasize possible harm to software, possible loss of data, or
possible service interruptions.
Typographic Conventions 1
This guide uses the following typographic conventions:
TCP/IP Transmission Control Protocol/Internet Protocol, a network-layer
protocol used on LANs and internets.
TFTP Trivial File Transfer Protocol, used to provide downloading of
upgrade scripts and application files to the IP Telephones.
UDP User Datagram Protocol, a connectionless transport-layer
protocol.
VLAN Virtual LAN.
This symbol precedes additional information about a topic. This information is not
required to run your system.
command Words printed in this type are commands that you enter into your
system.
device Words printed in this type indicate parameters associated with a
command for which you must substitute the appropriate value. For
example, when entering the mount command, device must be
replaced with the name of the drive that contains the installation disk.
Administrative Words printed in bold type are menu or screen titles and labels, or items
on menus and screens that you select to perform a task.
italics Italic type indicates a document that contains additional information
about a topic.
<Enter> Words enclosed in angle brackets represent a single key that should be
pressed. These include <Ctrl>,<Enter>, <Esc>, <Insert>, and
<Delete>.

4600 Series IP Telephone LAN Administrator’s Guide
Online Documentation
1-4
Online Documentation 1
The online documentation for the 4600 Series IP Telephones is located at the following URL:
http://avaya.com/support

Introduction
Related Documents
1-5
Related Documents 1
■DEFINITY Documentation Release 8.4
This CD contains documentation that describes, among other things, how to administer a
DEFINITY switch with Release 8.4 software.
This document is provided with the DEFINITY Release 8.4 product.
■DEFINITY Documentation Release 9
This CD contains documentation that describes, among other things, how to administer a
DEFINITY switch with Release 9 software.
This document is provided with the DEFINITY Release 9 product.
The following documents are available on the web site mentioned in ‘‘Related Documents’’
on page 1-5.
■4606/4612/4624 IP Telephones Set Up Quick Reference (555-233-201)
This document contains important user safety instructions for the 4600 Series IP Telephones.
■4600 Series IP Telephone Installation Guide (555-233-224)
This document describes how to install 4600 Series IP Telephones. It also provides
troubleshooting guidelines for the 4600 Series IP Telephones.
■4606 IP Telephone User Guide for DEFINITY Users
This document provides detailed information about using the 4606 IP Telephone.
■4612 IP Telephone User Guide for DEFINITY Users
This document provides detailed information about using the 4612 IP Telephone.
■4624IP Telephone User Guide for DEFINITY Users
This document provides detailed information about using the 4624 IP Telephone.
The following documents provide standards relevant to IP Telephony.
IETF Documents 1
The following documents are available for free from the IETF web site: http://www.ietf.org/
rfc.html.
Requirements for Internet Hosts - Communication Layers, October 1989, by R. Braden (STD
3: RFC 1122)
Requirements for Internet Hosts - Application and Support, October 1989, by R. Braden (STD
3: RFC 1123)
Internet Protocol (IP), September 1981, by Information Sciences Institute (STD 5: RFC 791),
as amended by Internet Standard Subnetting Procedure, August 1985, by J. Mogul and J.
Postel (STD 5: RFC 950)
Broadcasting Internet Datagrams, October 1984, by J. Mogul (STD 5: RFC 919)

4600 Series IP Telephone LAN Administrator’s Guide
Related Documents
1-6
Broadcasting Internet Datagrams in the Presence of Subnets, October 1984, by J. Mogul
(STD 5: RFC 922)
User Datagram Protocol (UDP), August 28, 1980, by J. Postel (STD 6: RFC 768)
Transmission Control Protocol (TCP), September 1981, by Information Sciences Institute
(STD 7: RFC 793)
The TFTP Protocol (Revision 2), (TFTP), July 1992, by K. Sollins, (STD 33: RFC 1350:) as
updated by TFTP Option Extension, May 1998, by G. Malkin and A. Harkin (RFC 2347)
An Ethernet Address Resolution Protocol (ARP), November 1982, by David C. Plummer (STD
37: RFC 826)
Dynamic Host Configuration Protocol (DHCP), March 1997, by R. Droms (RFC 2131)
DHCP Options and BOOTP Vendor Extensions, March 1997, by S. Alexander and R. Droms
(RFC 2132)
RTP: A Transport Protocol for Real-Time Applications (RTP/RTCP), January 1996, by H.
Schulzrinne, S. Casner, R. Frederick, V. Jacobson (RFC 1889)
Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers,
(DIFFSRV), December 1998, by K. Nichols, S. Blake, F. Baker and D. Black (RFC 2474)
Introduction to version 2 of the Internet-standard Network Management Framework
(SNMPv2), April 1993, by J. Case, K. McCloghrie, M. Rose, and S. Waldbusser (RFC 1441)
Management Information Base for Network Management of TCP/IP Internets: MIB-II, March
1991, edited by K. McCloghrie and M. Rose (RFC 1213)
SNMPv2 Management Information Base for the Internet Protocol using SMIv2, November
1996, edited by K. McCloghrie (RFC 2011)
Structure of Management Information Version 2 (SMIv2), April 1999, edited by K. McCloghrie,
D. Perkins, and J. Schoenwaelder (RFC 2578)
ITU Documents 1
The following documents are available for a fee from the ITU web site: http://www.itu.int.
Recommendation G.711, Pulse Code Modulation (PCM) of Voice Frequencies, November
1988.
Recommendation G.729, Coding of speech at 8 kbit/s using Conjugate-Structure Algebraic-
Code-Excited Linear-Prediction (CS-ACELP), March 1996.
Annex A to Recommendation G.729: Reduced complexity 8 kbit/s CS-ACELP speech codec,
November 1996.
Annex B to Recommendation G.729: A silence compression scheme for G.729 optimized for
terminals conforming to Recommendation V.70, November 1996.
Recommendation H.225.0, Call signalling protocols and media stream packetization for
packet-based multimedia communications systems, February 1998.
Recommendation H.245, Control protocol for multimedia communication, February 1998.
Recommendation H.323, Packet-based multimedia communications systems, February 1998.

Introduction
Customer Support
1-7
ISO/IEC, ANSI/IEEE Documents 1
The following documents are available for a fee from the ISO/IEC standards web site: http:/
/www.iec.ch.
International Standard ISO/IEC 8802-2:1998 ANSI/IEEE Std 802.2, 1998 Edition, Information
technology - Telecommunications and information exchange between systems - Local and
metropolitan area networks- Specific requirements- Part 2: Logical Link Control.
ISO/IEC 15802-3: 1998 ANSI/IEEE Std 802.1D, 1998 Edition, Information technology-
Telecommunications and information exchange between systems- Local and metropolitan area
networks- Common specifications- Part 3: Media Access Control (MAC) Bridges.
IEEE Std 802.1Q-1998, IEEE Standards for Local and Metropolitan Area Networks: Virtual
Bridged Local Area Networks.
Customer Support 1
For support for your 4600 Series IP Telephones, call the Avaya support number provided to you by
your Avaya representative or Avaya reseller.
Information about Avaya products can be obtained at the following URL:
http://avaya.com/support

4600 Series IP Telephone LAN Administrator’s Guide
Customer Support
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Contents
2-i
2
Overview of Voice over IP (VoIP)
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Overview of Voice over IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
■Data and Voice Network Similarities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
■Delay and Jitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■Tandem Coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■Voice Coding Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
■H.323 Standard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■TFTP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■NAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
■QoS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
SNMP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Network Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Suggestions for Installation and Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
■Reliability and Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
■Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
4600 Series IP Telephones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Dual Connection Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Registration and Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■WAN Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
■DHCP and DEFINITY Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6
Initialization Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 1: Telephone to Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 2: DHCP Server to Telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 3: Telephone and TFTP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
■Step 4: Telephone and the DEFINITY Server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8

4600 Series IP Telephone LAN Administrator’s Guide
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Introduction
2-1
2
Overview of Voice over IP (VoIP) 2
PIn
Introduction 2
This chapter describes the differences between data and voice networks, and the factors that
influence the performance of VoIP. The installation and administration of 4600 Series IP
Telephones on DEFINITY servers, and the installation and configuration of DHCP and TFTP are
addressed.
Overview of Voice over IP 2
The 4600 Series IP Telephones allow enterprises to use Voice over IP (that is, packet-switched
networks) instead of telephony over the Public Switched Telephone Network (PSTN). However,
the use of data networks for transmitting voice packets poses the problem that data networks were
not designed for the specific qualities required by voice traffic.
Data and Voice Network Similarities 2
Data and voice networks share similar functions due to the nature of networking.
■Signaling is used to establish a connection between two endpoints.
In a voice network, signaling is used to identify who the calling party is trying to call and where
the called party is on the network. Traditional telephony uses terminals with fixed addresses
and establishes a fixed connection for the communication session between two such
terminals, allocating fixed bandwidth resources for the duration of the call.
IP communications constitute a connectionless network, having neither fixed addresses nor
fixed connections.
■Addressing. Each terminal on a network must be identified by a unique address.
In a voice network the unique address is a permanent attribute, based on international and
national numbering plans, as well as those based on local telephone company practices and
internal customer-specific codes.
In IP communications, dial plans track extension numbers assigned to terminals. No fixed
connection path is needed.

4600 Series IP Telephone LAN Administrator’s Guide
Overview of Voice over IP
2-2
■Routing is related to addressing and allows connections to be established between
endpoints.
Though these functions are common to data and voice networks, the implementations differ.
Delay and Jitter 2
Data traffic is generally short and comes in bursts. Data networks like the Internet were designed
to manage these bursts of traffic from many sources on a first-come, first-served basis. Data
packets are sent to multiple destinations, often without any attempt to keep them in a particular
order.
Voice networks are designed for continuous transmission during a call. The traffic is not bursty,
and the conversation uses a specific amount of bandwidth between the two ends for the duration
of the call.
Several features of data networks are unsuitable for voice telephony:
■Data networks are designed to deliver data at the destination, but not necessarily within a
certain time. This produces delay (latency). In data networks, delay tends to be variable. For
voice messages, variable delay results in jitter, an audible chopiness in conversations.
■Variable routing also can result in loss of timing synchronization, so that packets are not
received at the destination in the proper order.
■Data networks have a strong emphasis on error correction, resulting in repeated
transmissions.
While data network concepts include prioritization of traffic types to give some forms of traffic
greater reliability (for example, for interactive transactions), data requirements tend to be not as
strict as most voice requirements.
Release 1.1 of the 4600 Series IP Telephones incudes a dynamic jitter buffer. This feature
automatically smooths jitter to improve audio quality.
Tandem Coding 2
Tandem coding (also called transcoding) refers to the conversion of a voice signal from analog to
digital and back again. When calls are routed over multiple IP facilities, they may be subject to
multiple transcodings. The multiple conversions between analog and digital coding result in a
deterioration in the voice quality. Tandem coding should be avoided wherever possible in any
compressed voice system (for example, minimizing analog trunking on the DEFINITY PBX).
Voice Coding Standards 2
There are a number of voice coding standards. The Avaya 4600 Series IP Telephones offer the
following options:
G.711, which describes the 64 kbps PCM voice coding technique. G.711-encoded voice is already
in the correct format for digital voice delivery in the public phone network or through PBXs.