130 CHAPTER 4: ADDING VCX TELEPHONES AND ATTENDANT CONSOLES
If all the ELINs associated with an ERL are in use, the default ERL
emergency callback number is used instead.
Additionally, you can specify a set of emergency gateways, which are
used to directly reach the emergency service if the call processor is
unavailable.
To ensure that emergency calls always go through, a set of system-wide
defaults are defined — the callback phone number and an emergency
gateway, identified by its IP address. These system defaults are used, for
example, if a phone is not associated with any ELIN or if the call processor
is down.
The emergency dialable digits are controlled by the ERL screens. If the
emergency digits are identified by an ERL then those emergency dialable
digits will not be applied a Class of Service treatment. Just because a
Class of Service Element is named Emergency and is blacklisted does not
mean that Emergency calls will not go through.
Note that a VCX phone can dial an emergency phone number even if the
phone is not logged in to the VCX system. However, the phone must be
properly configured with the IP address of the VCX call processor, have a
network connection to an operational VCX system, and the region must
support emergency dialing. If the VCX system is not operational, an
emergency call can be routed (optionally) directly through a PSTN media
gateway.L
CAUTION: You must ensure that a dial plan and dial pattern exist for
your emergency number, and that the dial plan is included in the phone
profile assigned to your users’ extensions. VCX software provides, by
default, a dial plan named Emergency that includes the emergency
numbers 911 and 9911. See Chapter 9 for information on patterns, dial
plans, and dial rules.
Emergency Calling
Considerations for
Roaming Users
As described in User Roaming Services, VCX software version 7.1 allows a
user to log in to any phone in the system, regardless of the call processor
to which the phone is connected. The user simply configures the phone
with his or her extension and logs in with the appropriate password. This
allows, for example, a user whose phone extension is configured at a
branch office, to assign that extension to a phone at regional office.
Consequently, the user’s branch extension and phone features are
enabled on the phone at the regional office.