Utah Communications Authoriy manages the 911 Program and the Vision for Next Generation 911.

Next Generation 911

Because most 911 systems were originally built using analog rather than digital technologies, public safety answering points (PSAPs) across the country need to be upgraded to a digital or Internet Protocol (IP)-based 911 system, commonly referred to as Next Generation 911 (NG911).

The success and reliability of 911 will be greatly improved with the implementation of NG911, as it will enhance emergency number services to create a faster, more resilient system that allows voice, photos, videos and text messages to flow seamlessly from the public to the 911 network.

NG911 will also improve PSAP ability to help manage call overload, natural disasters, and transferring of 911 calls and proper jurisdictional responses based on location tracking.

While the technology to implement these new IP-based 911 systems is available now, the transition to NG911 will involve much more than just new computer hardware and software. Implementing NG911 in states and counties nationwide will require the coordination of a variety of emergency communication, public safety, legislative and governing entities.

How does the existing 9-1-1 system work?

Voice calls are delivered to PSAPs by a system that uses data tables that relate telephone numbers to addresses. In the case of traditional landline calls, a third party contractor provides the information services that are used to pre-program the telecoms' 9-1-1 'selective routers' that quickly connect the 9-1-1 caller to their designated PSAP. These information services act as an intermediary between customer address information stored by each telecom and the Master Street Address Guide (MSAG), maintained by each PSAP. The MSAG is a table of valid address ranges and PSAP zone assignments. The caller's address location is delivered to the PSAP call taker through a separate service (referred to as Automatic Location Information or ALI) at or very near the time of the call connection. Keep in mind that, although updated to accommodate for wireless calls, the existing 9-1-1 system was originally architected in the mainframe era, well before a lot of what we now take for granted, like caller ID service, was a possible ingredient. (More info)

For landline and most VOIP calls, the telephone number is linked to a street address and that street address is what determines the primary PSAP to which the call is initially delivered. For wireless 9-1-1 calls, the call routing is based on a pre-determined PSAP assignment made for each antenna sector on the communicating tower, and the location of the calling device is subsequently delivered as geographic coordinates, generally within about 300 meters or less (E9-1-1 Phase 2 standards).

What is Next Generation 911 (NG 9-1-1)?

NextGen 9-1-1 is an initiative that seeks to upgrade the infrastructure, processes, and capabilities of the 9-1-1 systems. The primary upgrades include converting to an internet protocol (IP)-based communications backbone (referred to as ESI Net in NG speak), upgrading PSAP center call handling equipment (CPE) and handling additional communication mediums (text messaging, photos, video, etc). (More info)

Also, and of significant interest, the NG9-1-1 conversion will result in a transition from a complex system of telephone number tables, address tables, and PSAP zone assignment tables to an new environment where call connections are guided almost entirely based on digital mapping coordinates and GIS reference data layers. GIS road centerlines (with address ranges for each block) and address point datasets will be used to allow telecoms to pre-validate and store geographic coordinates for customer addresses on their own servers. The GIS data layers will provide improved precision for locating address-based incidents and, together with a web-editable PSAP zone boundary map layer, will allow for dynamic re-routing of calls in cases of PSAP downtime or overload.

In understanding and communicating community locations, humans work best with street addresses. Their computers and mobile devices work best with digital geographic coordinates. NG's GIS-driven approach, has a big advantage over the existing 9-1-1 systems tables because it allows for both human needs and computers' strengths to be realized. It also provides for a robust environment for visually inspecting and updating the important data resources that support the entire emergency response process from call routing to call taking to dispatch to field operations, and as needed, to business analysis.