Leading 911 systems vendor Intrado this week announced the successful completion of a trial in New York City to automatically locate 911 callers using a mobile voice-over-IP (VoIP) device and deliver the information to a public-safety answer point (PSAP).

The New York City test was the second such VoIP test in which Intrado has participated, with a similar test having been conducted in the Seattle area earlier this year. Unlike the Seattle effort—where VoIP calls were delivered to a test PSAP—the New York City trial delivered mobile VoIP calls to an actual PSAP, said Stephen Meer, Intrado’s chief technology officer.

“We showed that we were able to work with all those systems to deliver location information to a live 911 center … in a meaningful way,” he said.

Currently, VoIP providers depend on customers to update their addresses manually for the purpose of routing emergency calls. However, given the mobile nature of VoIP, that approach can lead to inaccurate call routing if customers fail to update their location in the 911 database.

With this in mind, Intrado is investigating possible ways to determine the location of a VoIP caller automatically. As with the Seattle test, the New York City trial used three different technologies—high-definition TV triangulation, Wi-Fi access point inventory information and thin-client technology that uses a combination of location technologies—to provide location information in the challenging New York City spectral environment, Meer said.

As expected, each technology demonstrated advantages and disadvantages, depending on the spectral environment in a given location, Meer said.

“What we’re trying to show the industry is that one size [of autolocation technology] does not fit all,” he said.

The accuracy of these location technologies is comparable to existing wireless E-911 technologies, which is not nearly as accurate as the address-specific locations PSAPs are accustomed to receiving from E-911 calls using the traditional wireline telephony network, Meer said. Getting industry and regulators to agree on the appropriate location accuracy criteria for VoIP E-911 will be important during the coming months, he said.