BellSouth E911 - Manual (Page 14)

Wireless E911 Guide CG-EWCG-001
Overview of E911 Issue 3, January 6, 2004
telephone number which has been assigned by the carrier, the carrier name, and the MSAG valid address
of the cell site sector location. A full description of the data fields in the TN database may be found
inTN Database Updates.
The TN database is updated by the wireless carrier on an ongoing basis as new pseudo-ANI numbers are
assigned or when existing information changes. This includes changes in antenna face coverage area when
it impacts routing of 911 calls to the appropriate PSAP. The data record which is sent by the wireless carrier
is validated against the MSAG for an exact address match and is assigned the appropriate ESN which is
loaded into the E911 host database and the E911 tandem routing database. Details for providing TN data
to the E911 host is explained later in this document. Some wireless solutions will dynamically update the
cell site location, call back number, longitude, and latitude during 911 call processing. Wireless carriers
are still required to provide "static" pseudo-ANI data records to the E911 host with MSAG valid addresses.
These "static" records will be dynamically updated during 911 call processing. The cell site location
information provided during the dynamic updates are not validated against the MSAG, but the original
"static" record provided in the SOIR process will be validated and must contain MSAG valid information.
Wireless Carriers must provide valid data records for inclusion in the TN database prior to testing or
activating service. If data records are not posted to the TN database, the PSAP will receive a "NO
RECORD FOUND" display when subscribers dial 911 which may delay getting them the emergency
services they need.
1.6 E911 Tandem / Network Information
Interconnection arrangements to the E911 tandem are negotiated with the wireless carrier’s BST
Interconnection Services Account Representative. The wireless carrier must provide a minimum of two
(2) Type 2C redundant trunks to the E911 tandem office(s) that will serve the Mobile Switching Center
(MSC). Additional facilities may be required depending on the technical solution used to dynamically pass
the wireless call back number and longitude/latitude to the ALI database. Data circuits must exist between
MPCs and the ALI database hosts for the E2 interface required for Phase 2.
Determining the proper PSAP to route wireless 911 calls must be negotiated between the wireless carrier
and the E911 Coordinators in the serving areas. This must also include the proper PSAP to receive the
wireless 911 call in the event of an ANI (pANI) failure from the MSC. All 911 calls will default route to
the negotiated PSAP when an ANI (pANI) failure occurs. E911 Coordinators must agree on the PSAP to
receive these calls. Once agreement has been reached with the E911 Coordinators, the wireless carrier will
notify the BST Interconnect Account Representative of the PSAP location for default routing. This will
allow for BST to establish the necessary translations in the E911 tandem office. The BST Interconnect
Account Representative may assist the wireless carrier in identifying which E911 tandem office should be
used to route calls to a specific PSAP.
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