Synchronizing GIS with MSAG & ALI

Document Information
Full name: 

NENA Information Document for Synchronizing Geographic Information System databases with MSAG & ALI

Document type: 


Standard number: 

71-501 v1

Document description: 

This document is the NENA information document for the synchronization of certain Geographic Information Systems (GIS) database layers with the Master Street Address Guide, the Automatic Location Information data, and optionally the site / structure locations.

This document is meant to provide PSAP management, vendors, and other interested parties necessary guidelines for synchronizing GIS data with existing 9-1-1 databases. The synchronization process of the GIS data is most reliably accomplished by qualified, trained individuals or vendors that have received formal GIS training and instruction.

This document is provided as a guide to synchronizing both the Master Street Address Guide (MSAG) and optionally the Automatic Location Information (ALI) databases to a Geographic Information System (GIS) geospatial database of road centerlines, site / structure locations, and related spatial databases. One must have a basic understanding of GIS concepts and MSAG data, or the resources available, in order to understand this document.

The preferred method for performing the synchronization is using various database techniques. Emergency Service Zones, MSAG and Postal Community Names, and optionally the ALI data and address point data will all be used in the synchronization process. The synchronization of these databases will improve the accuracy of the GIS data, the MSAG, and optionally the ALI data, aid in meeting the requirements for Next Generation 9-1-1(?) (NG9-1-1(?)) and improve the accuracy of the GIS data for Public Safety Answering Point (PSAP)(?) map display for all types of calls.

Once the corrections are made, the GIS road centerline file can then be used to validate addressing and to generate an up-to-date MSAG file for scrubbing service provider addresses.

Committee Information
Committee Name(s): 

Technical – Data

Committee Name(s): 

Operations – Next Generation Integration – NGI


Next Generation Data Development Working Group

Committee type: 

Joint Tech/Ops

Document Dates


Document Size
20090908_71-501_NENA Synchronizing GIS Databases with MSAG and ALI V1.1.pdf 266.27 KB