IP Capable Versus IP Enabled
Monday, June 01, 2009 | Comments



By Terry McLarty

For data to travel from point A to point B, a digital data line is required. Data can’t be carried by analog alone. About 80 percent of all voice communications worldwide are converted at some point to digital, including all long-distance calls; contrary to popular belief, not just VoIP calls are transferred over IP technology.

Next-Generation 9-1-1 (NG 9-1-1) will allow public-safety answering points (PSAPs) to receive many types of data — short message service (SMS), instant messaging (IM), text messages, images and video — from many different devices, such as cell phones, surveillance cameras and telematics systems such as OnStar. But it’s important to distinguish between IP-capable and IP-enabled systems. Many of the systems touting IP-capable functionality on the market fall short of the promise of NG 9-1-1 because of a lack of interoperability, a reliance on outdated analog converters, and a loss of data in the transition from IP to analog and then back to IP. IP-enabled systems, on the other hand, address the shortcomings of IP-capable systems and move the industry closer to the promise of true NG 9-1-1.

IP-Capable Systems

When a 9-1-1 call from an IP-capable provider is sent to a telco router, it’s converted from IP into an analog signal to travel over the centralized automatic message accounting (CAMA) trunk system to the controller at the PSAP where it’s then converted back into IP for delivery to the call-taker. During CAMA conversion, important supplemental data such as call information, geolocation and other types of media such as video is stripped away and can’t be delivered to the PSAP. Essentially, IP-capable systems try to convert apples into oranges and then back into apples. If the call needs to be transferred to a neighboring PSAP, IP-capable systems will strip all data from the call unless both PSAPs have the exact system from the same vendor, which in the increasingly competitive market is unlikely.

IP-Enabled Systems

IP-enabled systems don’t need to be converted from IP to analog back to IP, meaning that data remains an apples-to-apples-to-apples conversion that keeps all data intact. IP-capable systems promise the ability to transfer misrouted calls to neighboring PSAPs; however, this is only possible if both PSAPs have the same system from the same vendor. Because IP-enabled systems are designed on an open architecture, this requirement is eliminated and calls can be transferred to any other vendor’s system with all data intact. IP-enabled systems allow call-takers to log in remotely from anywhere in the world and work as if they were at their PSAPs.

Moreover, IP-enabled systems offer additional cost and timesavings compared with IP-capable systems. Multiple PSAPs in a region can join forces and purchase a centrally located controller, distributing the cost of expensive hardware without sacrificing functionality or moving staff to a centralized location. IP-enabled systems are also built with commercial-off-the-shelf (COTS) parts as opposed to specially manufactured pieces. With COTS components, the amount of support time spent waiting for replacement parts is reduced to how long it will take to get to Home Depot and back. Because IP-enabled systems aren’t converted to analog, the limitations of the one-to-one physical relationship of telephony circuits are eliminated — potentially reducing circuit delivery costs significantly.

While IP-capable systems fall short of promised NG 9-1-1 capabilities, IP-enabled systems are already capable of efficiently routing emergency data from various devices and systems in a flexible, cost-effective way that is bringing NG 9-1-1 closer to an industry reality.

Read more about IP-based 9-1-1 technology in the June issue of MissionCritical Communications.

Terry McLarty is the director, telephony design engineer and senior solutions architect for InterAct Public Safety. With more than 30 years of experience in the public-safety industry, McLarty previously served as assistant chair of the National Emergency Number Association’s (NENA) technical standards committee and is a member of NENA’s NG 9-1-1 partners program.

Your comments are welcome, click here.


Post a comment
Name: *
Email: *
Title: *
Comment: *


No Comments Submitted Yet

Be the first by using the form above to submit a comment!

Magazines in Print

May 2019

1 - 2
Comms Connect
Auckland, New Zealand

5 - 10
APCO Western Regional Conference 2019
Scottsdale, Arizona

More Events >

Site Navigation