Emergency 911 Dialing; 2-Way Did; Dialing Plan And Pri - Nortel BCM50 Configuration Manual

Emergency 911 dialing

(North America only)
The ISDN PRI feature is capable of transmitting the telephone number and internal extension
number of a calling station dialing 911 to the Public Switched Telephone Network (PSTN). State
and local requirements for support of Emergency 911 dialing service by Customer Premises
Equipment vary. Consult your local telecommunications service provider regarding compliance
with applicable laws and regulations. For most installations the following configuration rules
should be followed, unless local regulations require a modification.
• All PSTN connections must be over PRI.
• In order for all sets to be reached from a Public Safety Answering Position (PSAP), the system
must be configured for DID access to all sets. In order to reduce confusion, the dial digits for
each set should be configured to correspond to the set extension number.
• The OLI digits for each set should be identical to the DID dialed digits for the set.
• The routing table should route 911 to a PRI line pool.
• If attendant notification is required, the routing table must be set up for all 911 calls to use a
dedicated line which has an appearance on the attendant console.
• The actual digit string 911 is not hard-coded into the system. More than one emergency
number can be supported.
If transmission of internal extension numbers is not required or desired, Nortel recommends that
the person in charge of the system maintain a site map or location directory so that emergency
personnel can rapidly locate a BCM set given its DID number. Keep this list up-to-date and readily
available.
IP telephony note: Ensure that you do not apply a 911 route to an IP telephone that is off the
premises where the PSAP is connected to the system.

2-way DID

With PRI the same lines can be used for receiving direct inward dialing (DID) and for making
direct outward dialing (DOD) calls.
The dialing plan configured by your customer service representative determines how calls are
routed. Consult your customer service representative to determine whether or not this feature is
compatible with your service provider.

Dialing plan and PRI

The Dialing Plan supports PRI connectivity to public and private networks. The dialing plan is a
collection of features responsible for processing and routing incoming and outgoing calls. All PRI
calls must go through a dialing plan.
Notes about the dialing plan:
Appendix C ISDN overview
Networking Configuration Guide
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