Emergency Services Access 191
The Automatic Number Identification (ANI) data sent to the Public Safety
Answering Point (PSAP) identifies the location of the caller. In some
constituencies, legislation requires one ANI (DID) per fixed area, so
the physical location of the emergency can be approximated based on
the telephone number delivered to the PSAP. The ESA feature has a
comprehensive scheme that can be used to convert an extension into an
appropriate DID.
If the branch office is relatively small, it can be easier to use a single ANI
number for the branch office. For more information on this command, see
Software Input Output Reference—Maintenance (NN43001-711).
Routing Emergency Services Access (ESA) calls
ATTENTION
Do not route ESA calls to a node that has no direct ESA trunks.
Ideally,route ESA calls directly over Central Office (CO) trunks to the Public
Safety Answering Point(PSAP). In those cases where this routing is not
possible, do not routeESA calls to nodes that have no direct ESA trunks.
The implications of routing calls to nodes without direct ESA trunks are as
follows:
•At the node without the direct ESA trunks, the node cannot route the
ESA call directly to the PSAP.Instead, that node must re-route the call
to another node. This re-routing is an unnecessary use of resources.
•If the node is a CS 1000E node, the only tandem trunks are IP Peer
trunks. There is no way to specify the appropriate rerouting digits (that
is, Prepend Digits) to reroute the ESA callto another node with direct
ESA trunks.
Therefore, if unable to route ESA calls directly to the PSAP,the next best
practice is to route ESA calls to nodes with direct ESA trunks.
Emergency call routing
A Call Server can provide service to IP phones across multiple emergency
jurisdictions. This can also occur with traditional non-IP equipment in the
form of remote peripheral equipment (for example, Carrier Remote, Fiber
Remote).
An emergency call should be handled by the designated means for the
phone location (for example, local security desk or local PSAP). The
emergency call should be routed to a service at the current location of the
phone.
Nortel Communication Server 1000
Main Office Configuration Guide forSRG 50
NN43001-307 02.02 Standard
Release 5.0 3 December 2007
Copyright© 2005-2007, Nor tel Networks
.