Nortel CS 1000 Series User manual

Nortel Communication Server 1000
SIP DECT Fundamentals
Release: 6.0
Document Revision: 02.02
www.nortel.com
NN43120-123
.

Nortel Communication Server 1000
Release: 6.0
Publication: NN43120-123
Document release date: 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
While the information in this document is believed to be accurate and reliable, except as otherwise expressly
agreed to in writing NORTEL PROVIDES THIS DOCUMENT "AS IS" WITHOUT WARRANTY OR CONDITION OF
ANY KIND, EITHER EXPRESS OR IMPLIED. The information and/or products described in this document are
subject to change without notice.
Nortel, Nortel Networks, the Nortel logo, and the Globemark are trademarks of Nortel Networks.
All other trademarks are the property of their respective owners.
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3
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Contents
New in this release 7
Features 7
Other changes 7
Product overview 9
Navigation 9
Overview of SIP DECT 9
Universal extension support 12
DECT handset features 14
CallPilot and Message Waiting Indication support 15
SIP DECT capacity limitations 16
Site planning and hardware deployment 17
Navigation 17
Components of SIP DECT systems 17
Call server, Signaling server, and SIP Line Gateway 17
PC (DAP controller) 18
DECT Access Points 18
Deployment requirements 18
Navigation 19
Radio synchronization 19
IP network configuration 23
Location requirements 26
Types of SIP DECT configuration 28
Site planning 32
Site survey 32
Speech quality 33
Coverage calculation 35
Traffic density calculations 38
System deployment 38
DECT Deployment Kit 2 38
Deployment terms 42
Deploying on a single floor 44
Deploying on multiple floors 59
Reengineer cells for high traffic areas 63
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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4
Software requirements 79
Navigation 79
Call server, signalling server, and SIP Line Gateway software 79
DAP controller software 79
Firewall protection 80
Internet information services 80
DHCP and TFTP servers 87
DAP Controller 102
SIPN configuration 107
Navigation 107
Basic (simple) SIP DECT configuration with CS 1000 SIP Gateway 107
Configuration using IP DECT Configurator 108
DAP manager configuration 120
Configuration on Element manager 124
NRS configuration 133
Call server configuration 140
Branch Office configuration 143
Routed Head Quarter configuration 146
Configure Routed Head Quarter 147
Routed Head Quarter Configuration with Branch Office 148
Multi site mobility network configuration 150
Subscribe a multiple-site DECT handset 151
Import and export subscriptions 151
Configure NRS for multiple-site mobility network 152
Call server configuration to MSMN 153
Configuration of Personal Call Assistant 156
Configuration of UEXT on the remote system 157
SIPL configuration 159
Navigation 159
Basic (simple) SIP DECT configuration with CS 1000 SIP Line Gateway 159
Configuration using IP DECT Configurator 159
DAP manager configuration 173
SIP Line Gateway configuration 177
Call server configuration 177
Branch Office configuration 180
Routed Head Quarter configuration 182
Configure Routed Head Quarter 183
Routed Head Quarter Configuration with Branch Office 185
Multiple-site mobility network configuration 187
Subscribe a multi-site DECT handset 187
Import and export subscriptions 188
Personal Call Assistant configuration 189
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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5
System administration 191
Navigation 191
DAP manager overview 191
Subscription management 193
Subscribing a handset 193
Edit a subscription RPN 194
Disable a subscription 195
Removing a subscription 196
Deleting a number 196
Use the filter 197
Handset status 198
DAP management 200
Changing a DAP Radio Part Number 200
Restarting a DAP 201
Restart all DAPs 201
Deleting a DAP 202
Add a DN range 202
Importing a DN range from a .csv file 203
System backup 205
Subscription export and import 205
Export subscriptions 205
Import subscriptions 208
DAP reboot history 208
System archive 209
Handset firmware update 210
Central directory access tool 214
Supported database types 215
Installation 216
Configure SIP DECT for Central directory access 217
System maintenance 219
Navigation 219
DAP Web interface 219
DAP LED indications 221
DAP firmware update 221
Remove and replace a DAP (if a new DAP is available) 223
Remove and replace a DAP (if a new DAP is not available) 224
System synchronization analysis 225
Synchronization Analyzer interface 226
Export and import SIP DECT system 233
Export a system 233
Import a system 234
DAP Controller deactivation 235
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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6
Uninstalling DAP Controller software 236
DAP Controller software update 237
Troubleshooting 238
If DAP is not working 238
If you cannot make calls from a DECT handset to an IP/TDM telephone on the
call server (SIPN Configuration) 239
If you cannot make calls between DECT handsets (SIPN Configuration) 240
If you cannot make calls to or from a DECT handset with SIPL
configuration 242
If you have problems 244
System survey 244
DAP information file 245
System archive 245
Network packet capture traces 246
Location builder tool 247
Use the Location builder tool 247
Create a location file 249
Maintenance 254
Site survey example 257
Site planning example: Able-Studio 257
The facts for Able-Studio 257
The site survey for Able-Studio 257
Deployment tool 263
Prepare the tool for deployment 264
Charging the deployment tool battery 265
Charging the deployment handset battery 266
Assembling the deployment tool 267
Testing the deployment handset 270
How the deployment tool works 271
Using the deployment tool 272
Handset tones interpretation 273
Rules for outdoor deployment 273
External housing installation 275
Installing a C4710 basestation in an external housing 275
Installing a C4710E basestation in an external housing with an external
antenna 278
Mounting the cabinet on a wall 280
Mounting the cabinet on a pole 281
Third Party Software 283
SRTP 283
TLS 284
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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7
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New in this release
The following section details what is new in SIP DECT Fundamentals
(NN43120-123).
Features This document is updated to document SIP DECT on SIP LINE.
Other changes
This section describes the detailed history of past releases of this
document.
Revision History
Date Description
March 2010 Standard 02.02. This document is up-issued with information
for SIP DECT on SIP LINE, and to support Communication
Server 1000 (CS 1000) Release 6.0.
October 2009 Standard 02.01. This document is up-issued to reflect changes
in technical content stemming from SIP DECT 4.2, and to
support CS 1000 Release 6.0.
January 2009 Standard 01.07. This document is up-issued for CS 1000
Release 5.5 with editorial changes.
December
2008 Standard 01.06. This document is up-issued for CS 1000 Release 5.5, in response to change requests for content related
to SIP DECT 4.1.
July 2008 Standard 01.05. This document is up-issued in response to
change requests.
July 2008 Standard 01.04. This document is up-issued in response to
change requests.
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
.

8New in this release
Date Description
May 2008 Standard 01.03. This document is up-issued in response to
change requests.
March 2008 Standard 01.02. This document is up-issued in response to
change requests.
February
2008 Standard 01.01. This is a new document issued to support
CS 1000 Release 5.5. Some of the information in this new
document was previously contained in the following document:
DECT Fundamentals (NN43120-114).
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
.

9
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Product overview
This section describes the capabilities, configuration, and design of SIP
DECT.
Navigation •“Overview of SIP DECT” (page 9)
Overview of SIP DECT
You can use Nortel Session Initiation Protocol (SIP) Digital Enhanced
Cordless Telecommunications (DECT) to move without restriction about
your work site while conducting telephone conversations, using wireless
handsets. The Nortel SIP DECT system includes one or more DECT
access points (DAPs or basestations) connected to the TLAN.
The system supports the following connection types for SIP DECT
configuration:
•SIPL configuration, which uses SIP Line Gateway
•SIPN configuration, which uses the Signaling Server
ATTENTION
This document describes both SIPN and SIPL connection types. Some sections
of this document discuss only SIPN or SIPL, while other sections cover
both, and contain notes concerning the differences between SIPN and SIPL
configuration. When you configure Nortel SIP DECT, ensure that you follow the
procedures for the configuration type that you require.
•SIPL connections are available on CS 1000 Release 6.0 and later, and use
SIP Line Gateway nodes to connect SIP clients to the Call Server. SIPL
connections support SIP DECT handset registration, and require that you
create a SIPL subtype of UEXT blocks on the Call Server.
•SIPN connections are available on CS 1000 Release 5.5 and later, and are
normally used only on that release. SIPN connections are based on SIP
trunks between SIP Gateway (Signaling Server) and NRS. SIPN connections
don’t support SIP DECT handset registration, and require that you create a
SIPN subtype of UEXT blocks on the Call Server.
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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10 Product overview
A minimal SIP DECT system has the following main components.
•Call Server
•SIP Line Gateway or Signaling Server (according to configuration type)
•PC with DAP controller software installed
•DAP
•handset
Use the following tools to configure SIP DECT.
•Element manager or overlay program for Call Server
•Element manager and, if required, Network Routing Service (NRS)
manager for Signaling Server
•IP DECT Configurator—used to enter SIP DECT configuration
•DAP Manager (IP DECT Manager)—a Web interface used for SIP
DECT administration tasks such as adding a handset or removing a
subscription.
The IP DECT Configurator and the DAP manager IP DECT are available
as a part of the DAP controller software package.
The following software releases are required for the main system
components:
•Call Server, Release 6.0
•Signaling Server, Release 6.0
•DAP software 4910b427.dwl or later
•DAP controller 4.2 or later (PC software)
You can connect IP phones to the TLAN, and you can connect TDM
phones to the Call Server, Voice Gateway Media Cards, and other
required cards in Call Server. Use Voice Gateway Media Cards for
IP-to-TDM calls and for conference calls involving IP phones or DECT
handsets on basestations. The configuration can also include a PC with
DECT Messenger to provide the DECT messaging service on SIP DECT.
For SIP DECT to function properly on SIPN configurations, you must install
a dedicated Signalling Server running the SIP Gateway application. You
can use other applications, such as H.323 Gateway, NRS, and IP Phones,
on the same Signaling Server without limitations.
Use the Dynamic Host Control Protocol (DHCP) server or the Trivial File
Transfer Protocol (TFTP) server unless you use a DAP configuration
without DHCP or TFTP. You can configure the system to use two separate
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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Overview of SIP DECT 11
servers: one for DHCP and the other for TFTP. If the system requires
DAP configuration without DHCP or TFTP, the DHCP or TFTP server is
required during installation or configuration changes.
The following figure shows a general SIP DECT configuration.
Figure 1
SIP DECT configuration
You can install the DHCP or TFTP services, DECT Messenger, and DAP
controller on a single server or PC. However, you can also install them on
separate servers to enhance performance or facilitate administration. You
can also install Element Manager, NRS manager, and Telephony Manager
on the same server if the server has both a TLAN network interface and an
ELAN network interface. If the server you use cannot support all of these
applications, you can use more than one server.
You connect the DAP to the Communication Server 1000 (CS 1000)
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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12 Product overview
•in SIPN configuration using the SIP trunks that you configure between
the Signaling Server and the NRS
•in SIPL configuration using the SIP-line trunks that you configure for
SIP Line Gateway
Each DAP communicates with the subscribed DECT handsets in the
coverage area, and each DAP interacts with the CS 1000 and with other
configured DAPs in the company network.
You can run SIP DECT on the following configurations:
•Communication Server 1000M or Communication 1000E
•Signaling Server running SIP Gateway (SIPN only) or Signalling Server
running SIP Line Gateway
Use the SIP Redirect Server or SIP Proxy Server to perform the
appropriate NRS configuration for SIP DECT (SIPN connection type):
•You can run SIP Redirect Server on Internet Server Platform (ISP)
1100s, Call Processor Pentium Mobile (CP PM) signaling servers,
or on IBM or HP Commercial-off-the-shelf (COTS) servers under
VxWorks.
•You can run SIP Proxy Server on IBM or HP COTS servers under
Linux. You can run SIP Redirect Server on the same Signaling Server
as SIP Gateway dedicated to SIP DECT.
•You can run SIP Redirect Server on a stand-alone Signaling Server.
If you install SIP Proxy Server you must use a stand-alone COTS server.
You cannot run SIP Gateway on the same server as the SIP Proxy Server.
Universal extension support
DECT handsets subscribed on DAPs are external to CS 1000. The CS
1000 does not control the state of DECT handsets. Therefore, the CS
1000
•cannot detect individual key presses on DECT handsets
•cannot control cadences on DECT handsets
•cannot detect if a DECT handset is switched off and on
•cannot control the handset display content
A DECT handset subscribed on a DAP cannot use the same range of
features available to analog, digital, or UNIStim IP phones on the CS 1000.
The Universal Extension (UEXT) feature on the Call Server provides
Configuration and status information for subscribed DECT handsets.
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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Overview of SIP DECT 13
No Associated Telephone (AST) or Computer-Telephone Integration (CTI)
capabilities are currently available for SIP DECT.
Each DECT handset has a local Directory Number (DN) in CS 1000. Use
this local DN to subscribe the corresponding DECT handsets on the SIP
DECT system through DAP Manager. DAP manager is available on the
server where you installed the DAP controller.
Configure the UEXT associated with a DECT handset as follows:
•For the Primary DN of the UEXT (key 0 SCR), enter the local DN
associated with the DECT handset.
•On SIPN configurations, for the Target DN of the UEXT (key 1 HOT P),
enter the digits required to access the SIP route (SIP Trunks)
configured to access DAPs plus the local DN of the handsets. This
consists of one of the following values:
—For access based on the configured Coordinated Dialing Plan
(CDP), compose the Target DN as follows:
<TSC>+<LOCAL DN>.
—For access based on the configured Uniform Dialing Plan (UDP),
compose the Target DN as follows:
<AC1 or AC2>+<LOC>+<LOCAL DN>.
•For SIPL configuration for the Target DN of the UEXT (key 1 HOT U),
enter the digits of the User agent prefix (SIP Line configuration item)
plus the local DN of the handsets.
A UEXT corresponding to a DECT handset on the SIP DECT system
reflects the idle or busy status of the associated handset by a check for a
call processed between the handset and a DAP.
The Integrated SIP DECT provides the following UEXT features.
•Make and receive simple calls
•Call Hold. Only one active call and one call on hold can exist for a
handset
•Consultative or Announced Call Transfer
•Blind Call Transfer
•Conference call participation if another party adds the DECT handset
to the conference
•Start a three-way call (SIPL configurations only)
•Calling Line ID (CLID) and Calling Party Name Display (CPND) for
simple calls not involving call transfer
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SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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14 Product overview
•CLID and CPND for an internal line (digital or IP phone with display)
calling to or receiving a call from a DECT handset
•Sending DTMF tones through the established connection to interact
with the called line (party), for example, to work with CallPilot
•Support for a voice mailbox on CallPilot and Message Waiting
Indication (MWI)
•Call Forward No Answer
•Call Forward By Time of Day
•Call Forward Busy
•Hunting
•Call Restrictions applicable to a UEXT
•Twinned configuration (typically a desk phone plus a DECT handset)
DECT handset features
The user of a DECT handset subscribed on SIP DECT can perform the
following actions:
•Make calls to DNs except restricted or blocked DNs.
•Receive and answer calls from the Call Server. If CPND is available,
the name of the caller and DN appear on the handset display. The
position and appearance of the name DN on the display depend on the
firmware installed on the handset.
•Place the active call on hold by pressing the R key on the handset.
Return to the held call by pressing the R key. If a call is on hold,
another call can be made from the handset. After the second call is
established, the user can switch between the two calls with the R key.
•Transfer a call to another DN
—To perform a Blind Transfer
Place the current call on hold, call the required DN and immediately
release from the call.
—To perform a Consultative Transfer
Place the current call on hold, call the required DN, wait for the
answer and release the call after the DN answers.
•Press digit keys on the handset during an established call to transmit
DTMF tones to the other party on the call.
•For SIPL configurations only, you can initiate a three-way call. Place
an active call on hold, call the third party and wait until the call is
answered. Press the star (*) key to start the conference.
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SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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Overview of SIP DECT 15
If your system uses SIPN, you cannot use a DECT handset to configure
Call Forward or Hunting or to configure Call Restrictions. If the system
uses a twinned configuration, you can use the twinned desk phone to
configure Call Forward for the Primary DN with the existing keys or with
Flexible Feature Codes (FFC).
On SIPL configurations, you can activate FFC features such as Call
Forward, Make Set Busy, Ring Again, Call Park, which are available for
SIP Line users.
CallPilot and Message Waiting Indication support
DECT handsets subscribed on SIP DECT can use CallPilot.
You can configure Call Forward No Answer for the Primary DN of the
UEXT so that the unanswered calls on the corresponding DECT handset
or IP phone (in the case of a twinned configuration) are forwarded to
CallPilot. Calls can also be forwarded to CallPilot as busy treatment for
the Primary DN.
A user can call the CallPilot system from a DECT handset and log on to
the voice mailbox with the corresponding DN and password. The user can
then use the voice menus of the system as usual.
The system can send MWI to the DECT handset through the SIP Trunk.
If your system uses SIPL, enter the MWI primary DN of the SIP DECT
user. For SIPN configurations, configure additional DNs (to which CallPilot
sends MWI) for the voice mailbox corresponding to the UEXT Primary DN.
The additional DN configured in CallPilot is the external DN of the DECT
handset, which is the Target DN on the UEXT corresponding to the DECT
handset.
CS 1000 supports only the Unsolicited MWI NOTIFY model. An external
SIP UA cannot SUBSCRIBE to MWI NOTIFY messages and cannot
request the current status of MWI for the DN from the system (by sending
SUBSCRIBE messages). Instead, a SIP UA must be ready to receive MWI
NOTIFY messages from the system even if it did not SUBSCRIBE, and it
must update MWI according to those messages only.
For SIPN configurations, due to the Unsolicited MWI NOTIFY model used
in SIPN, the DECT handset relies on the MWI notifications sent by CS
1000. Therefore, the MWI based on the existing mechanism can be in the
incorrect state on the DECT handset if the handset was turned off and
on. The MWI can be in the incorrect state if the handset leaves and then
reenters the coverage area of the SIP DECT. In this situation, the MWI on
the DECT handset returns to the correct state when the next MWI state
change occurs in the CallPilot system.
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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16 Product overview
If you use a twinned configuration for a DECT handset, the corresponding
IP or TDM phone correctly reflects the current state of MWI, if it receives
MWI notifications for the Primary DN from CallPilot.
SIP DECT capacity limitations
The following capacity limitations apply to SIP DECT:
•a maximum of 12 simultaneous calls for each DAP
•a maximum of 256 DAPs on each network (where handover and
synchronization between DAPs is possible)
•a maximum of 6000 DECT handsets on each SIP DECT system
(potentially, several isolated SIP DECT systems can connect to CS
1000)
•a maximum of 1000 simultaneous calls on each network
•a maximum of 25 subscription records for each DAP
If the planned number of DECT handsets in a SIP DECT system is
equal to M, and the number of DAPs in that system is equal to N, M
must be less than or equal to N*25.
Consider the following additional capacity limitations based on the CS
1000 configuration characteristics.
•The number of available UEXTs is limited by the number of available
virtual Telephone Numbers (TN) in the system.
•The number of DNs available for DECT handsets depends on the
configured dialing plan and the availability of the Directory Number
Expansion (DNXP) package (150).
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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17
.
Site planning and hardware
deployment
Navigation •“Components of SIP DECT systems” (page 17)
•“Deployment requirements” (page 18)
•"Types of SIP DECT configuration" (page 28)
•“Site planning” (page 32)
•“System deployment” (page 38)
Components of SIP DECT systems
This section contains information about the following topics.
•“Call server, Signaling server, and SIP Line Gateway” (page 17)
•“PC (DAP controller)” (page 18)
•“DECT Access Points” (page 18)
Call server, Signaling server, and SIP Line Gateway
Before you install SIP DECT you must install and configure a CS 1000
system, as follows:
•For SIPN configuration, install Call Server and Signaling Server.
•For SIPL configuration, install Call Server and SIP Line Gateway.
For more information about SIP Line Gateway, see SIP Line Fundamentals
(NN43001-508).
CS 1000 Release 6.0 introduces the CP PM Co-resident Call Server
and Signaling Server (CP PM Co-res CS and SS), which can run the
Call Server software, the Signaling Server software, and the System
Management software on the same hardware platform operating under
the RedHat Linux operating system.
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SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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18 Site planning and hardware deployment
For more information about CS 1000 installation, see Communication
Server 1000E Installation and Commissioning (NN43041-310).
PC (DAP controller)
Minimum specifications for the DAP controller PC are as follows.
•2.4 GHz CPU
•512 MB RAM
•CD-ROM drive
•1GB free hard disk space
DECT Access Points
Two models of DECT Access Points (DAP) are currently available for
Nortel SIP DECT: C4710 and C4710E. The C4710E is a special version
of the C4710 Access Point that provides an alternative with an external
antenna connection for outdoor use.
•C4710 DAP
—PEC: NTCW26AAE5
—CPC: N0162007
•C4710E DAP
—PEC: NTCW26BAE5
—CPC: N0162008
ATTENTION
The only audio codec supported on the C4710 and C4710E DAPs is the G.711
codec. Ensure that the G.711 codec is available in your system.
It is not possible to make calls between the Nortel IP Softphone 2050 and DECT
handsets when you select the I use a modem to connect to the network
check box in the Audio settings for the softphone. If you select this setting, the
Nortel IP Softphone 2050 uses the G.729 codec for all calls.
When using Multimedia PC Client, ensure that you select Medium Speed or
High Speed in the Multimedia PC Client Connection preferences if you plan to
make calls between DECT handsets and Multimedia PC Clients.
Ensure that the DAPs are installed according to the location
recommendations. For more information, see “Deployment requirements”
(page 18).
Deployment requirements
This section describes SIP DECT deployment requirements.
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SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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Deployment requirements 19
Navigation
•“Radio synchronization” (page 19)
•“IP network configuration” (page 23)
•“Location requirements” (page 26)
Radio synchronization
The radio network structure supports seamless handover of existing calls.
This means that, during a call, if a handset moves from the coverage area
of one DAP into the coverage area of another DAP, the new DAP can
take over the call. The call is not interrupted, and the user is not aware of
the handover. In the traditional DECT system, synchronization between
DAPs occurs over the wired network. SIP DECT requires an accurate
synchronization of the radio signals in the air to support handover.
ATTENTION
If a DAP cannot receive synchronization signals from at least one other DAP, it
operates in a single cell mode and cannot handover to other DAPs or receive
handover from them.
Represent each DAP cell as a circle indicating the radio signals around
the DAP. Figure 2 "DAP radio signal synchronization" (page 20) shows
two circles around the DAP.
•an inner circle in which sufficient radio signal strength exists for
acceptable voice quality
•an outer circle in which sufficient signal strength exists for
synchronization, but not enough for acceptable voice quality
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
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20 Site planning and hardware deployment
Figure 2
DAP radio signal synchronization
Due to the cellular structure of a DECT radio network, overlap exists in
the cells with sufficient voice quality. The wider cell limit around the DAP
therefore has some overlap with the other cell and reaches to the radio of
the other cell. Consequently, the DAPs of the overlapping cells exchange
radio signals. These radio signals are weak relative the signal needed by
the handsets, but are strong enough for synchronization.
ATTENTION
For signal strength calculation see “Signal strength and frame errors” (page 22).
If one DAP receives a signal from another, the receiving DAP checks the
radio signals on Primary Access Right Identity (PARI), to ensure that the
signals belong to the same DECT system. If the signals belong to the
same DECT system, the DAPs synchronize according to user-configured
rules.
Nortel Communication Server 1000
SIP DECT Fundamentals
NN43120-123 02.02 30 March 2010
Copyright © 2008-2010 Nortel Networks. All Rights Reserved.
.