Public Safety and the Move to IP

This article originally appeared in the Sept. 2011 issue of Next Gen Mobility

Over the next few years, the way in which public safety systems deliver the necessary services to people will be changing fundamentally. The transition from traditional TDM-based public safety answering points, or PSAPs, to IP-based networks and capabilities has already begun, and has been driven by the National Emergency Number Association, which recently announced its formal approval of the i3 standard for next-generation 911 architectures.  

The i3 standard can be described as IMS-like in terms of the architecture, and I believe this was done intentionally to allow public safety to keep up with technology advances as they come along, rather than trying to develop their own technology. In fact, there are many references to the work of standards development organizations that are being leveraged, especially with the use of SIP.

With more than 6,000 PSAPs in existence, the transition to IP will take time, but there are many benefits to the switch. For instance, many PSAPs are county-based; however, when moving to IP, there are many cost savings for counties that make the transition together.   Coordinating the IP rollout at a state level provides even more benefits, including the expansion of capabilities in times of emergency, and backup and resiliency enabled by failover from one PSAP to another. The Emergency Services IP network, also known as ESInet, can be shared across a number of different emergency services to further improve cost savings, as long as the necessary SLAs are in place to ensure that 911 calls are prioritized.

Within the traditional TDM-based network, there is a reliance on copper lines to enable the necessary communications with citizens and the contacting of, and conferencing in of, first responders. With the move to IP, copper lines will no longer be needed. This will allow data pipes to deliver multiple calls over an IP network and to expand the information being passed, thus enabling the steady addition of new features and functionality. As a first point, NG911 systems need to replicate the capabilities of the current E911 systems before any new features and capabilities can be added. For instance, when moving to the IP-based systems, the location of the callers remains critical, so ensuring these and other features remain is of utmost importance. However, future capabilities also need to remain a criterion, so selections of systems, software and equipment should allow a move into the new areas of functionality.

NG911 systems will have broader data capabilities than E911 systems and will offer additional modes of communication beyond just voice, including the ability for citizens, call takers and emergency responders to communicate via text, image and video. For example, consider being able to send an image of an emergency to a 911 call taker, or being able to receive video instructions on how to deal with an emergency until first responders arrive?  The ability to transfer data such as maps, video surveillance and other important information will likely be possible.

These changes also broaden the range of service providers that can deliver these new capabilities. The break from the use of copper lines allows for second tier service providers to deliver the necessary connectivity options for these services, making this market more competitive. As part of the i3 standard, the interconnectivity to legacy networks and parts of the public safety systems not already transitioned to IP is accounted for through a range of gateways that ensure the important links are kept in place. Over time, with the network going all-IP and the expectation that networks outside the control of the public safety will move to IP, these gateways will eventually not be needed, but that will be some time away. 

Security into this important IP network will be delivered through session border control and firewall capabilities in a border control function. It is important that the networks are secure and all necessary precautions are taken to deal with the various threats that IP networks can be subjected to.

With the changes coming to the public safety networks and PSAPs, there are many benefits that will become apparent in terms of interconnectivity, cost and interaction among the emergency services. The transition of data from voice to text, video and image will provide many benefits to both citizens and emergency responders.

Jim Machi is senior vice president of marketing at Dialogic (News - Alert) Inc. (www.dialogic.com).