Administrator's Guide

Features and technical reference
555-233-5061672 Issue 5 October 2002
calls from a station on a PBX not equipped with CAMA trunks (or an adjunct
computer system associated with CAMA trunks) will not provide the E911 system
with the information required to identify the location of the person placing the
call. Instead, the E911 system will only be able to identify the location of the trunk
termination at the PBX.
This feature allows transmission of identifying information in the form of the
CESID over CAMA trunks as to the extension number of a DID station associated
with the calling party. The calling party may be at or near a station on a remote
port network, or may be at a remote location served by an off-premises station.
Considerations
■ Emergency response personnel might go to the wrong location when
extensions and IP phones are moved without notifying the system
administrator.
■ The ANI that is sent to the CO might not be the same extension as that of
the phone used to dial emergency personnel. If the call is disconnected and
emergency personnel call back they will call the ANI and may not be able
to reach the person who placed the call. However, if the emergency
location phone had a crisis alert button, the return call would be answered
by someone who was notified of the extension making the emergency call.
That person could forward the return call from the emergency personnel to
the extension that made the emergency call. See “Crisis Alert”.
■ Emergency response personnel can be sent to the wrong location during the
time between an IP phone registering after a move and the time that the
system administrator updates the emergency location extension field.
■ Enhancements to E911 only applies to emergency calls on CAMA and
ISDN trunks.
■ Several call appearances should be provided on the last phone in the
Emergency Location Extension’s coverage path and station hunting path.
■ Emergency Location Extensions should not include voice mail, automated
attendant or announcement extensions.
Emergency Transfer
Emergency Transfer provides service to and from the local telephone company
CO during a power failure or when service is impaired. Emergency Transfer is
also called Power Failure Transfer; the terms are synonymous.