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Résumé du contenu

Page 1 - IP Telephony Configuration

Part No. P0937663 03.1Business Communications Manager 2.5IP Telephony Configuration Guide

Page 2 - Trademarks

10 FiguresP0937663 03.1 Figure 41 Peak traffic, WAN link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104Figure 42 C

Page 3 - Contents

100 Efficient NetworkingP0937663 03.1 Some WAN links can exist on top of layer 2 services such as Frame Relay and Asynchronous Transfer Mode (A

Page 4 - Chapter 4

Efficient Networking 101IP Telephony Configuration Guide The peak bandwidth and average bandwidth requirements for a normal two-way call must t

Page 5 - Chapter 5

102 Efficient NetworkingP0937663 03.1 With no silence suppression, both the transmit path and the receive path continuously transmit voice pack

Page 6 - Appendix A

Efficient Networking 103IP Telephony Configuration Guide With no silence suppression, both the transmit path and the receive path continuously

Page 7

104 Efficient NetworkingP0937663 03.1 WAN engineeringWide Area Network (WAN) links are typically full-duplex links - both talk and listen traff

Page 8

Efficient Networking 105IP Telephony Configuration Guide Additional feature configurationThis section contains additional information on config

Page 9

106 Efficient NetworkingP0937663 03.1 Consider there are four IP telephony ports per site. Each site supports four VoIP ports. Assume the codex

Page 10

Efficient Networking 107IP Telephony Configuration Guide Enough link capacityTable 15 sorts the computations so that for each link, the availab

Page 11

108 Efficient NetworkingP0937663 03.1 Other intranet resource considerationsBottlenecks caused by non-WAN resources do not occur often. For a m

Page 12 - 12 Tables

Efficient Networking 109IP Telephony Configuration Guide • Queuing delay: The queuing delay is the time it takes for a packet to wait in the tr

Page 13 - Symbols used in this guide

11IP Telephony Configuration Guide TablesTable 1 Network diagram prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Tab

Page 14 - Acronyms

110 Efficient NetworkingP0937663 03.1 Adjust the jitter buffer sizeThe parameters for the voice jitter buffer directly affect the end-to-end de

Page 15 - Related publications

Efficient Networking 111IP Telephony Configuration Guide Routing issuesRouting problems cause unnecessary delay. Some routes are better than ot

Page 16 - How to get help

112 Efficient NetworkingP0937663 03.1

Page 17 - Introduction

113IP Telephony Configuration Guide Appendix BSilence compressionSilence compression reduces bandwidth requirements by as much as 50 per cent. This ap

Page 18 - IP telephones and VoIP trunks

114 Silence compressionP0937663 03.1 When silence compression is enabled, voice packets are only sent when a speaker is talking. In a typical v

Page 19 - Figure 1 Network diagram

Silence compression 115IP Telephony Configuration Guide Silence compression on Full Duplex LinksOn full duplex links, the transmit path and the

Page 20 - Telephones

116 Silence compressionP0937663 03.1 When several calls are made over a full duplex link, all calls share the same transmit path and they share

Page 21 - IP network

117IP Telephony Configuration Guide Appendix CNetwork performance utilitiesThere are two common network utilities, Ping and Traceroute. These utilitie

Page 22 - Key IP telephony concepts

118 Network performance utilitiesP0937663 03.1

Page 23 - QoS routing

119IP Telephony Configuration Guide Appendix DInteroperabilityBusiness Communications Manager 2.5 IP Telephony adheres to the ITU-T H.323v2 standards,

Page 24

12 TablesP0937663 03.1

Page 25 - Prerequisites checklist

120 InteroperabilityP0937663 03.1 Speech path setup methodsBusiness Communications Manager 2.5 currently only initiates calls using H.323 slowS

Page 26 - Network assessment

Interoperability 121IP Telephony Configuration Guide Asymmetrical media channel negotiationBy default, the Business Communications Manager IP T

Page 27 - Keycodes

122 InteroperabilityP0937663 03.1

Page 28 - Defining published IP address

123IP Telephony Configuration Guide Appendix EQuality of ServiceThe users of corporate voice and data services expect these services to meet a level o

Page 29

124 Quality of ServiceP0937663 03.1 The QoS level is aligned for user QoS metrics to provide an acceptable Mean Opinion Score (MOS) level. The

Page 30 - NetVision wireless telephones

Quality of Service 125IP Telephony Configuration Guide Notice from the Ping output the difference of rtt. The repeated sampling of rtt allows y

Page 31 - Installing IP telephones

126 Quality of ServiceP0937663 03.1 The Traceroute program checks if routing in the intranet is symmetric for each source destination pairs. Al

Page 32

Quality of Service 127IP Telephony Configuration Guide Late packetsPackets that arrive outside of the window allowed by the jitter buffer are d

Page 33 - Choosing a codec

128 Quality of ServiceP0937663 03.1 Other measurement considerationsThe Ping statistics described above measure the intranet before IP telephon

Page 34 - Before installing

Quality of Service 129IP Telephony Configuration Guide Traffic mixThis section describes QoS works with the IP telephony, and what new intranet

Page 35 - Using a 3-port switch

13IP Telephony Configuration Guide PrefaceThis guide describes IP Telephony functionality for the Business Communications Manager 2.5 and 2.5 plus Fea

Page 36 - Manual Cfg DHCP(0 no, 1 yes)

130 Quality of ServiceP0937663 03.1 Business Communications Manager router QoS supportWith a Business Communications Manager system, the VoIP g

Page 37 - Field Value Description

Quality of Service 131IP Telephony Configuration Guide Note 3: Fallback starts for all new originating calls if the QoS of any monitored gatewa

Page 38

132 Quality of ServiceP0937663 03.1 Fallback to PSTNIf the measured Mean Opinion Score (MOS) for all codecs is below the configured threshold f

Page 39

133IP Telephony Configuration Guide Glossaryaccess pointThis is a piece of hardware that has a hardwire connection to the internet and acts as a wirel

Page 40 - Changing the contrast level

134 GlossaryP0937663 03.1 G.729A codec that provides near toll quality at a low delay. Uses compression to 8 kbit/s (8:1 compression rate). G.723.1

Page 41 - Configuring DHCP

Glossary 135IP Telephony Configuration Guide published IP addressThe IP address that both the IP telephones and the Symbol NetVision telephones use

Page 42 - Figure 6 Configuration menu

136 GlossaryP0937663 03.1

Page 43

IP Telephony Configuration Guide137IndexNumbers3-port switchIP telephones 35relocating IP telephones 47Aabsorbed length 73access codeline pool

Page 44 - Download Pending

138 IndexP0937663 03.1computed load 126computer, IP telephoney prerequisites 30Conference Call 120configureDN record 38i2050 Software Phone

Page 45

Index 139 IP Telephony Configuration Guideend to end delay 108, 124end to end DTMF signaling 119end-to-end packet loss, measuring 125errorsga

Page 46 - Customizing feature labels

14 PrefaceP0937663 03.1 Text conventionsThis guide uses these following text conventions:AcronymsThis guide uses the following acronyms:Note: Note/

Page 47 - Moving IP telephones

140 IndexP0937663 03.1Hunt group, target line to DN 76Ii2002connecting 83server parameters 37i2004connecting 83feature labels 46keep DN a

Page 48 - Keep DN alive

Index 141 IP Telephony Configuration Guiderouter IP 37server parameters 37Set IP, viewing 38settings 42slow connection 40staggered downlo

Page 49 - Figure 12 i2050 Switch type

142 IndexP0937663 03.1Media path redirection 119media resources, prerequisite 27Meridian 1(also see M1)M1-ITG 59MCDN networking 93profile

Page 50 - 7 Click on the BCM option

Index 143 IP Telephony Configuration Guideusing a gatekeeper 88VoIP destination digits 67WAN engineering 104networksVLAN ports 30NEW SET

Page 51

144 IndexP0937663 03.1remote gateway 66status display 86updating data 86qualitative scale, QoS 124Quality of Service Monitor (see QoS monit

Page 52 - Configuring NetVision records

Index 145 IP Telephony Configuration GuideSL-1MCDN fallback 94MCDN over VoIP 67slow connection 40slowStart 119Sniffer 117source gateway

Page 53 - <http:/

146 IndexP0937663 03.1adding to DN records 65codecs 60configuration 59configuring incoming calls 76configuring NetMeeting clients 84conne

Page 54

Preface 15IP Telephony Configuration Guide Related publicationsDocuments referenced in the Business Communications Manager 2.5 IP Telephony Configu

Page 55 - Testing the handset functions

16 PrefaceP0937663 03.1 How to get help• USA and CanadaAuthorized Distributors - ITAS Technical Support Telephone: 1-800-4NORTEL (1-800-466-7835)If

Page 56

17IP Telephony Configuration Guide Chapter 1IntroductionIP Telephony provides the flexibility, affordability, and expandability of the Internet to the

Page 57 - Changing a handset Name

18 Chapter 1 IntroductionP0937663 03.1 IP telephones and VoIP trunksThis guide describes two similar applications for IP telephony on the Busine

Page 58

Chapter 1 Introduction 19IP Telephony Configuration Guide Creating the IP telephony networkThis section explains the components of the Business

Page 59 - Configuring VoIP trunks

2 P0937663 03.1 Copyright © 2002 Nortel NetworksAll rights reserved. The information in this document is subject to change without notice. The

Page 60 - Configuring media parameters

20 Chapter 1 IntroductionP0937663 03.1 Business Communications Manager 2.5The Business Communications Manager 2.5 is a key building block in cre

Page 61 - Setting silence compression

Chapter 1 Introduction 21IP Telephony Configuration Guide VoIP trunks and analog/digital telephonesWhile analog and digital telephones cannot be

Page 62 - Setting jitter buffers

22 Chapter 1 IntroductionP0937663 03.1 The Business Communications Manager 2.5 Programming Operations Guide has a data section that describes th

Page 63 - Outgoing call configuration

Chapter 1 Introduction 23IP Telephony Configuration Guide If you experience poor voice quality, and suspect it is due to heavy network traffic,

Page 64 - Figure 18 Trunk/Line data

24 Chapter 1 IntroductionP0937663 03.1 The header contains the network address of the sending and receiving IP telephones, and a TOS (Type Of Se

Page 65

25IP Telephony Configuration Guide Chapter 2Prerequisites checklistBefore you set up VoIP trunks or IP telephones on a Business Communications Manager

Page 66 - Configuring a remote gateway

26 Chapter 2 Prerequisites checklistP0937663 03.1 Network assessmentTable 3 questions are meant to ensure that the network is capable of handlin

Page 67

Chapter 2 Prerequisites checklist 27IP Telephony Configuration Guide Resource assessmentAnswer the questions in Table 4 to determine if you have

Page 68 - Configuring PSTN fallback

28 Chapter 2 Prerequisites checklistP0937663 03.1 Business Communications Manager system configurationSeveral sections of the Business Communica

Page 69 - Setting up the VoIP schedule

Chapter 2 Prerequisites checklist 29IP Telephony Configuration Guide Determining the published IP addressUse the flowchart in Figure 3 to determ

Page 70 - Configuring routes

3IP Telephony Configuration Guide ContentsPreface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 71

30 Chapter 2 Prerequisites checklistP0937663 03.1 IP telephonesComplete this section if you are installing IP telephones. Table 7 IP telephone

Page 72

31IP Telephony Configuration Guide Chapter 3Installing IP telephonesAn IP telephone converts the voice signal into data packets and sends these packet

Page 73 - Figure 26 VoIP schedule

32 Chapter 3 Installing IP telephonesP0937663 03.1 Configuring Nortel Networks i-series telephonesThe configuration menus for the Nortel Network

Page 74 - Activating the VoIP schedule

Chapter 3 Installing IP telephones 33IP Telephony Configuration Guide 6 In the Advertisement/Logo box, type a string of text characters. This me

Page 75 - Turning on QoS monitor

34 Chapter 3 Installing IP telephonesP0937663 03.1 Choosing a Jitter BufferA jitter buffer is used to prevent the jitter associated with arrivin

Page 76 - Incoming call configuration

Chapter 3 Installing IP telephones 35IP Telephony Configuration Guide Using a 3-port switchIn an office environment where a LAN network already

Page 77

36 Chapter 3 Installing IP telephonesP0937663 03.1 When the telephone registers, it downloads the information from the Business Communications M

Page 78 - Example configuration

Chapter 3 Installing IP telephones 37IP Telephony Configuration Guide Table 8 describes the value for each parameter and what they mean.Table 8

Page 79

38 Chapter 3 Installing IP telephonesP0937663 03.1 When you have entered all the configuration information, the telephone attempts to connect to

Page 80

Chapter 3 Installing IP telephones 39IP Telephony Configuration Guide If an IP telephone does not bootIf the telephone does not boot, use the fo

Page 81

4 ContentsP0937663 03.1 IP telephones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 82 - Making calls

40 Chapter 3 Installing IP telephonesP0937663 03.1 Telephone does not connect to systemIf an IP telephone does not display the text Connecting t

Page 83 - Connecting an i200X telephone

Chapter 3 Installing IP telephones 41IP Telephony Configuration Guide Configuring DHCPYou can use Distributed Host Control Protocol (DHCP) to au

Page 84

42 Chapter 3 Installing IP telephonesP0937663 03.1 Modifying settings for Nortel IP telephonesSettings such as jitter buffers and codecs for the

Page 85

Chapter 3 Installing IP telephones 43IP Telephony Configuration Guide 5 From the menu, select Modify Codec/Jitter Buffer. The IP Terminal Status

Page 86 - Port settings

44 Chapter 3 Installing IP telephonesP0937663 03.1 Download firmware to a Nortel IP telephoneFirmware is the software stored in the telephone. W

Page 87 - Using firewalls

Chapter 3 Installing IP telephones 45IP Telephony Configuration Guide Deregistering DNs for IP telephonesYou can deregister selected telephones

Page 88 - Using a gatekeeper

46 Chapter 3 Installing IP telephonesP0937663 03.1 Customizing feature labelsWhen your IP telephone acquires a DN record, the default settings a

Page 89 - The call signaling method

Chapter 3 Installing IP telephones 47IP Telephony Configuration Guide 3 If you have an existing list, or you do not want to change any defaults,

Page 90

48 Chapter 3 Installing IP telephonesP0937663 03.1 4 If the new location is on a different LAN or WAN from the old location, the subnet mask, de

Page 91 - Gatekeeper call scenarios

Chapter 3 Installing IP telephones 49IP Telephony Configuration Guide Configuring the Nortel Networks i2050 Software PhoneThe Nortel Networks i2

Page 92

Contents 5IP Telephony Configuration Guide Assigning H.323 Terminals records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 93 - Typical applications

50 Chapter 3 Installing IP telephonesP0937663 03.1 7 Click on the BCM option.8 Enable the Select Sound Devices tab for the USB headset.To furthe

Page 94

51IP Telephony Configuration Guide Chapter 4Installing NetVision telephonesThis chapter describes how to configure the Symbol NetVision handsets to th

Page 95 - Setting up the system

52 Chapter 4 Installing NetVision telephonesP0937663 03.1 Handset and call functionsSymbol supplies a handset user guide that describes the feat

Page 96

Chapter 4 Installing NetVision telephones 53IP Telephony Configuration Guide Gathering system information before you startEnsure the following i

Page 97

54 Chapter 4 Installing NetVision telephonesP0937663 03.1 Users Wizard. This wizard is explained in the Business Communications Manager 2.5 Prog

Page 98

Chapter 4 Installing NetVision telephones 55IP Telephony Configuration Guide 3 In the Name field, type in the name of the user of the handset.4

Page 99 - Efficient Networking

56 Chapter 4 Installing NetVision telephonesP0937663 03.1 Updating the H.323 terminals recordIf you need to change the password for a NetVision

Page 100 - Network engineering

Chapter 4 Installing NetVision telephones 57IP Telephony Configuration Guide Changing a handset NameThe Name is the primary point of recognition

Page 101

58 Chapter 4 Installing NetVision telephonesP0937663 03.1 4 Click Yes to delete the record.Under the Systems DNs heading, the DN record returns

Page 102

59IP Telephony Configuration Guide Chapter 5Configuring VoIP trunksThis chapter explains how to configure voice over IP (VoIP) trunks on a Business Co

Page 103 - LAN engineering examples

6 ContentsP0937663 03.1 Port settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 104 - WAN engineering

60 Chapter 5 Configuring VoIP trunksP0937663 03.1 Configuring media parametersThere are three steps to configuring media parameters:• Configurin

Page 105 - Setting Non-linear processing

Chapter 5 Configuring VoIP trunks 61IP Telephony Configuration Guide Setting silence compressionThis section explains how to set silence compres

Page 106 - Traceroute

62 Chapter 5 Configuring VoIP trunksP0937663 03.1 Setting jitter buffersThis section explains how to select the jitter buffer size used on VoIP

Page 107 - Not enough link capacity

Chapter 5 Configuring VoIP trunks 63IP Telephony Configuration Guide Outgoing call configurationThis section explains how to set up your system

Page 108 - Further network analysis

64 Chapter 5 Configuring VoIP trunksP0937663 03.1 To put your lines into a line pool:1 In Unified Manager, click on the keys beside Services, Te

Page 109 - Reducing hop count

Chapter 5 Configuring VoIP trunks 65IP Telephony Configuration Guide 7 Click on the line pool that you selected as the VoIP line pool.The Pool s

Page 110 - Reduce packet errors

66 Chapter 5 Configuring VoIP trunksP0937663 03.1 Configuring a remote gatewayThis section explains how to configure the Business Communications

Page 111 - Routing issues

Chapter 5 Configuring VoIP trunks 67IP Telephony Configuration Guide Figure 21 Remote gateway dialog3 In the Name field, type a name for the r

Page 112

68 Chapter 5 Configuring VoIP trunksP0937663 03.1 If you intend on using fallback to a PSTN line, set the QoS monitor to enabled. Otherwise, set

Page 113 - Silence compression

Chapter 5 Configuring VoIP trunks 69IP Telephony Configuration Guide For PSTN fallback to work, you must ensure that the digits the user dials w

Page 114

Contents 7IP Telephony Configuration Guide Adjust the jitter buffer size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 115

70 Chapter 5 Configuring VoIP trunksP0937663 03.1 2 Change the Service setting to Manual. 3 Change the Overflow setting to Y.Configuring routesC

Page 116 - Comfort noise

Chapter 5 Configuring VoIP trunks 71IP Telephony Configuration Guide PSTN (to local PSTN lines):a Click the Add button. b In the Add routes dial

Page 117 - Network performance utilities

72 Chapter 5 Configuring VoIP trunksP0937663 03.1 Creating destination codes for fallbackCreate a destination code that includes the VoIP and PS

Page 118

Chapter 5 Configuring VoIP trunks 73IP Telephony Configuration Guide 6 Click on the key beside Schedules, and highlight VoIP. The VoIP schedule

Page 119 - Interoperability

74 Chapter 5 Configuring VoIP trunksP0937663 03.1 In this case, the user dials the destination code plus the DN. The destination code is absorbe

Page 120 - Gatekeeper

Chapter 5 Configuring VoIP trunks 75IP Telephony Configuration Guide Turning on QoS monitorFor fallback to function, the QoS monitor must be ena

Page 121 - Symbol NetVision telephones

76 Chapter 5 Configuring VoIP trunksP0937663 03.1 Incoming call configurationTo receive an incoming call directly to the telephone from a VoIP n

Page 122 - 122 Interoperability

Chapter 5 Configuring VoIP trunks 77IP Telephony Configuration Guide 4 Enter the number of an available target line (241-412). 5 Click the Save

Page 123 - Quality of Service

78 Chapter 5 Configuring VoIP trunksP0937663 03.1 Example configurationThis section walks through a sample Business Communications Manager confi

Page 124 - Measuring Intranet QoS

Chapter 5 Configuring VoIP trunks 79IP Telephony Configuration Guide On Business Communications Manager OttawaThis procedure details actions tha

Page 125 - Recording routes

8 ContentsP0937663 03.1 Network Quality of Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130Netwo

Page 126 - Adjusting Ping measurements

80 Chapter 5 Configuring VoIP trunksP0937663 03.1 7 The installer sets up the VoIP schedule with these settings:• Service: Manual• Overflow: Y8

Page 127 - Measurement procedure

Chapter 5 Configuring VoIP trunks 81IP Telephony Configuration Guide 3 The installer configures the media for the system, using the following se

Page 128 - 128 Quality of Service

82 Chapter 5 Configuring VoIP trunksP0937663 03.1 11 The installer creates a destination code of 2.• Under the Normal schedule, the installer as

Page 129 - TCP traffic behavior

Chapter 5 Configuring VoIP trunks 83IP Telephony Configuration Guide Connecting an i200X telephoneThis section takes the example above and uses

Page 130 - Network Quality of Service

84 Chapter 5 Configuring VoIP trunksP0937663 03.1 Remote access over VoIP trunksYou cannot program DISA or auto-answer for voice over IP (VoIP)

Page 131 - Quality of Service parameters

Chapter 5 Configuring VoIP trunks 85IP Telephony Configuration Guide 3 Click Advanced Settings.The advanced settings dialog appears.Figure 31

Page 132 - Fallback to PSTN

86 Chapter 5 Configuring VoIP trunksP0937663 03.1 Quality of Service MonitorThe Quality of Service Monitor is an application that monitors the q

Page 133 - Glossary

Chapter 5 Configuring VoIP trunks 87IP Telephony Configuration Guide Using firewallsFirewalls can interfere with communications between the Busi

Page 134 - 134 Glossary

88 Chapter 5 Configuring VoIP trunksP0937663 03.1 4 Change the port settings.5 Click the Save button.Port settings for legacy networksBusiness C

Page 135 - Glossary 135

Chapter 5 Configuring VoIP trunks 89IP Telephony Configuration Guide The call signaling methodThe call signaling method defines how the Business

Page 136 - 136 Glossary

9IP Telephony Configuration Guide FiguresFigure 1 Network diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page 137

90 Chapter 5 Configuring VoIP trunksP0937663 03.1 Modifying the call signaling methodTo modify the call signaling method:1 In the Unified Manage

Page 138

Chapter 5 Configuring VoIP trunks 91IP Telephony Configuration Guide Gatekeeper call scenariosThis section explains what must be set up, and how

Page 139

92 Chapter 5 Configuring VoIP trunksP0937663 03.1 If call signaling is set to Gatekeeper Routed and no pre-granted ARQ has been issued:1 Busines

Page 140

93IP Telephony Configuration Guide Chapter 6Typical applicationsThis section explains several common installation scenarios and provides examples abou

Page 141

94 Chapter 6 Typical applicationsP0937663 03.1 Setting up MCDN over VoIP with fallbackTo set up this system:1 Make sure the M1 ITG meets the fol

Page 142

Chapter 6 Typical applications 95IP Telephony Configuration Guide Networking multiple Business Communications ManagersThe system shown in Figure

Page 143

96 Chapter 6 Typical applicationsP0937663 03.1 This system uses fallback to PSTN so calls can be routed across the PSTN connection if VoIP traff

Page 144

Chapter 6 Typical applications 97IP Telephony Configuration Guide Setting up the call chain configurationTo set up this system:1 Ensure that the

Page 145

98 Chapter 6 Typical applicationsP0937663 03.1 Setting up a remote-based IP telephoneTo set up this system:1 Ensure that each remote user has a

Page 146

99IP Telephony Configuration Guide Appendix AEfficient NetworkingThis appendix provides information about making your network run more efficiently. De

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