CG-IEIK-001 Issue 4-August 1, 2005

Once the county draws the jurisdictional boundaries for the police, fire, and ambulance services on the map(s), the ESNs are assigned. Each of the geographic areas, in which all residents are serviced by the same set of selected agencies, will be assigned the same ESN if they all route to the same PSAP and selective routing is not used to route other agency calls to secondary answering positions.

The ESNs are three(3) digit numbers which BST will provide. BST, the ICO, and the county will jointly assign the ESNs on the map(s). Once the ESNs are assigned, the ICO will use the map information to identify the streets within each ESN boundary. This information is provided to BST to use in the creating of the MSAG (Master Street Address Guide). The MSAG will be used to programmatically assign an ESN to each subscriber's telephone number in the county. Special consideration should be given to Voice of Internet Protocol (VoIP) service. Refer to the BellSouth VSP E911 Guide for details on VoIP service."

The county will verify all data, including ESNs, on the MSAG and will provide changes to the ICO and BST. The procedures for creating the MSAG and making changes are covered later in this document.

Once the boundaries are defined, assign ESNs to each segment.

ESN 001	ESN 002	ESN 003	ESN 004	ESN 005	ESN006	ESN 007
P1	P2	P2	P2	P1	P1	P2
F1	F1	F2	F2	F2	F2	P2
A1	A1	A1	A2	A2	A1	A2

Verify postal zip code and incorporated area boundaries.