Nortel Networks NN43001-314 - Manual (Page 319)

Emergency Services Access (ESA) 319
The basic ESA feature only provides for a single ESA route per system.
Since all IP Phones are associated with the same main office, all ESA calls
therefore go to the same Public Safety Answering Point (PSAP) regardless
from which Branch Office they originated. This is not satisfactory if the
branch offices are widely dispersed.
In general, ESA calls should leave the network through a trunk at the
Branch Office where the originating telephone is located. To enable this,
it is necessary for telephones at each Branch Office to supply a unique
identifying prefix to the NRS when the ESA calls are being routed so that
the NRS can select a distinct route for each Branch Office. This prefix
can be configured with the zone data for the MG 1000B telephones. The
provisioning of this prefix is an enhancement for Branch Office.
While a variety of numbering schemes are available, Nortel recommends
that customers use "0" + the ESN location code of the MG 1000B + ESDN,
where ESDN is:
• for North America and CALA — "911"
• for members of the European Union — "112" and any other emergency
numbers in use prior to the EU directive
This number, referred to here as the ESA Special Number, is configured as
a special number (SPN) in the NRS so that the Virtual Trunk routes the call
to the Branch Office.
Procedure 37
Configuring the main office
Step Action
You can use Element Manager or the Command Line Interface for this
procedure. Refer to IP Peer Networking Installation and Commissioning
(NN43001-313) for details.
1 Configure the main office emergency trunk (CAMA or PRI).
Configure either analog CAMA or digital PRI to correctly signal the
call identification.
ESA overrides all security features. Configure the trunk with
restrictions so that other features cannot access the trunk.
2 Configure the Virtual Trunk using the procedure from IP Peer
Networking Installation and Commissioning (NN43001-313) .
The Virtual Trunk must be configured to enable emergency calls
originating from MG 1000B IP Phones registered at the main office
to reach the Branch Office.
3 Configure ESN.
Nortel Communication Server 1000
Branch Office Installation and Commissioning
NN43001-314 01.02 Standard
Release 5.0 20 June 2007
Copyright © 2007, Nortel Networks
.