# Emergency Services - CESID Support Description

## Description

A Customer Emergency Services ID (CESID) is used to provide location information for a phone extension on a private network, when a caller makes an emergency call. The information can help direct emergency responders to a caller's location. CESID programming and maintenance is a required component of Emergency Services. Additionally, SIP messaging allows SIP endpoints to send location information to the MiVoice Business through:

1. Geolocation by Reference

2. CESID

3. BSSID

CESIDs are public network Listed Directory Numbers (LDNs) that you obtain from a local carrier. You can assign CESID to

- each directory number (DN) on your network, using the CESID Assignment form,

- a device, using the L2 to CESID Mapping,

- a network zone, using the Network Zones form, or

- the whole system, using the Default CESID form.

When an emergency call is made, the system sends the CESID of the extension out to the PSTN. The CESID is used by the central office (CO) to route the call to the local Public Safety Answering Point (PSAP) and then by the PSAP to call up information such as the address, building, floor, area, and callback number. Mitel CESID support complies with Emergency Services regulations (such as the FCC's Enhanced 911 standards) requiring PBXs to support CESIDs.

CESIDs can be manually or automatically updated to maintain current CESID information in the system. See CESID Maintenance.

CESIDs and their assigned location information are stored in an Automatic Location Information (ALI) database. See Coordinating CESID with the ALI Database.

CESIDs are not dialable numbers and the data contained in them is only used for outbound Emergency calls. CESID numbers are never displayed to a 3rd party during a routine call.

NOTE: Different state or provincial regulations may govern the CESID requirements at your location. Some require a unique CESID for every telephone, and others allow the sharing of CESIDs if the telephone users are within sight of one another. One dialable "callback" number is required for each CESID.

## Coordinating CESID with the ALI Database

The CESID sent to the PSAP to identify the location of the emergency caller must be the same number that resides in the Automatic Location Information (ALI) database for that location. The ALI database is independent of MiVoice Business and may reside at the local PSAP, at the telephone company Central Office, or at an independent location. It is essential that CESID numbers and the ALI database remain synchronized when moves, adds, and changes take place. Any changes made to a user's location or data associated with a CESID must be communicated to the ALI database administrator. Ensure that local changes affecting ALI information are kept from going into service until the ALI database has been updated. The System Administrator must ensure that CESID related changes are communicated to the ALI database.

Related Topics

- Emergency Services - CESID Conditions

- Emergency Services - CESID Guidelines

- Emergency Services - CESID Programming

- Emergency Services - CESID Maintenance

- Emergency Services Description