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Cox Business Trunking Service - E911 Practice Statement

Please read this statement carefully for important Customer obligations.
Cox Business trunking services (including PRI and SIP trunking services) are interconnected with the emergency 911 network so that 911 calls are routed to Public Safety Answering Points ("PSAPs").

PSAPs access location information on 911 calls through the Automatic Location Information Database ("ALI Database") based on the telephone number of the incoming call. This allows responders to determine the Customer's address if the caller is unable to provide it to the PSAP when a 911 call is placed from Customer's location.


Customer Responsibility for Testing

It is Customer's responsibility to conduct initial and regular testing of the ability to dial 9-1-1 over Cox Business services and ensure that: 1) Customer Premises Equipment ("CPE") is compatible with Cox Business's services; 2) the PSAP is able to indentify the Customer's address when a 911 call is placed from Customer's location; and, if Customer is using a PS-ALI service to provide enhanced PS/ALI functions (as described below), that 3) the PSAP is able to indentify the specific location within Customer's address from where the 911 call is placed. (See Section 5, Testing 9-1-1 Call Processing for PBX Systems; NENA Technical Information Document No. 03-502, "Trunking for Private Switch 9-1-1 Service," available at 


Customer Responsibility for Enhanced PS/ALI

Cox Business supports the use of enhanced Private Switch / Automatic Location Information ("PS/ALI") functions where the CPE and Cox Business's facilities permit such enhanced PS/ALI functions. Such functions permit CPE to register specific PBX stations in the ALI Database to direct emergency responders to specific locations such as specific floors or specific buildings on a campus.

If Customer chooses to use enhanced PS/ALI functions, Customer is responsible for acquiring PS/ALI service at Customer's sole expense. It is Customer's sole responsibility to inform Cox Business and to confirm with Customer's PBX vendors and manufacturers that CPE is compatible with the technical requirements needed to provide PS/ALI using the trunking services purchased from Cox Business. Further, it is Customer's sole responsibility to register and maintain location information in the ALI Database and ensure that the PBX switch employs telephone numbers provided with the Cox Business services for 911 signaling. Customer is responsible for testing the ability to dial 9-1-1 from lines associated with PBX systems at the time the systems and/or new PBX trunks are installed or upgraded and conducting periodic testing thereafter.


Customer Options at Time of Install

Cox Business trunking Customers must inform Cox of Customer's desired 911 configuration. Currently Cox Business supports two 911 configuration options:

1. BILLING TELEPHONE NUMBER ("BTN"): This option may not meet the needs of larger organizations (customer decision) or when one PBX serves multiple physical locations.

As a default, Cox Business will register the trunking Circuit BTN in the ALI Database with the Customer's trunking service address. It is the Customer's responsibility to outpulse the trunking Circuit BTN to the PSAP when 911 calls are made from Customer's location. As a default, and where technically supported, Cox Business will transmit the BTN to the PSAP when a 911 call is made over the trunk. Where it is not technically supported for Cox Business to transmit the BTN as a default, Customer must program its equipment to outpulse the BTN. National Emergency Number Association ("NENA") guidelines state that if any PBX that has not implemented a PS/911 enhancement, the BTN should be sent as the telephone number for 9-1-1 calls. (See NENA Technical Information Document No. 03-502, "Trunking for Private Switch 9-1-1 Service," available at
2. INDIVIDUAL AUTOMATIC NUMBER IDENTIFICATION ("ANI"): This option is more expansive than option 1 and can be used, for example with campus, private network or multi-site environments and/or multi-floor building locations.

If the Customer informs Cox Business it wishes to utilize enhanced PS/ALI functions, Customer must confirm that the configuration of CPE and Cox Business facilities permits such PS/ALI functions. The Customer is responsible for retaining a PS/ALI vendor and setting up and maintaining such enhanced PS/ALI arrangements. Customer must inform Cox Business that it wishes to utilize enhanced PS/ALI functions in order that Cox Business may pass telephone numbers outpulsed from the Customer's equipment to the PSAP. Customer is then responsible for ensuring that CPE outpulses the telephone numbers provided with the Cox Business service to the PSAP when a 911 call is placed from Customer's location.

Customer may contact their local Cox Business office with any questions regarding this E911 practice. Cox recommends Customer review carefully the following NENA documents available at

• NENA Technical Information Document (NENA 03-502), "Trunking for Private Switch 9-1-1 Service"

• NENA Standard (NENA 06-003) "Private Switch (PS) E 9-1-1 Database Standard"

This Practice Statement is subject to change from time to time. Notices referenced in this document must be provided in accordance with the notice requirements set forth in the applicable agreement between Cox Business and the Customer. This Practice Statement supersedes and replaces any 911 or E911 Practice or Policy Statement that Cox Business may have provided to Customer in the past, except that this Practice Statement does not supersede any 911 or E911 language contained in any written agreement between Cox and Customer.

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