New legislation and a notice of proposed rulemaking (NPRM) from the Federal Communications Commission aim to address lingering incompatibilities between emergency number or 911 service and voice-over-IP service.

Since Vonage and others began providing VoIP service over customers’ broadband connections several years ago, they have faced a unique problem. Unlike with traditional phone service, VoIP-over-broadband customers can move their service from one address to another simply by moving their computer or analog terminal adapter. That can result in the call being routed to emergency personnel at the wrong public safety answering point (PSAP) and incorrect address information being sent if a customer dials 911. In regulatory jargon, VoIP-over-broadband service is “nomadic”--in contrast with fixed VoIP service, such as that offered by the cable companies, which cannot easily be transported.

Today providers of nomadic VoIP service are required to offer customers a means of updating their address information, such as through a Web browser. But that’s not a perfect solution because it relies on the customer to voluntarily provide the updates.

The FCC’s proposed rulemaking would require nomadic VoIP providers to support automatic location capability with an accuracy equivalent to what wireless service providers must support. But opponents, including companies involved in providing nomadic VoIP, said the technology isn’t ready. “We haven’t seen anything enabling that yet,” said Steve Seitz, vice president of regulatory affairs for Vonage.

A solution based on global positioning such as those used to support wireless 911 may not provide sufficient granularity, Seitz noted. Location information for wireless 911 can be off by 10 or 15 meters, said Seitz. While that may be fine for rescuing someone on a highway, he said, “If you talk about a multi-dwelling unit, such as a dorm, people live in less than 10 meters. If your latitude or longitude is off, people won’t like their door being kicked in.”

“We believe we provide excellent location information today,” added Seitz. “If you talk about automatic location information, it should meet or be better than what we have today.”

Although it does not provide retail VoIP services, Level 3 Communications is heavily involved in delivering VoIP on a wholesale basis and offers a 911 solution that is used by many nomadic VoIP providers. J.P. Gonzalez, director of E911 product delivery for Level 3, agreed that it’s too soon to impose automatic location requirements for nomadic VoIP.

“It may be good to move in that direction, so long as you’re not overly aggressive with the time frame,” he said. “The time frame needs to align with the technical ability to do it. Wireless providers were given many years.”

Gonzalez believes a mixture of technologies will be required to provide automatic location information for nomadic VoIP. “The access provider will probably play a big role in this,” he predicted. “Every Ethernet port has a physical location, but the voice service provider doesn’t necessarily know where that is.”

Another concern about nomadic VoIP is that neither providers of the service nor the PSAPs supporting it have the same liability protection that they do for traditional wireline and wireless calls. Callers using traditional wired or wireless service to call 911 are prevented from suing the network operator or the PSAP except in certain cases.

“It doesn’t cover gross negligence, only something not foreseeable that is not due to any particular party,” explained a spokesman for the National Emergency Number Association, which represents PSAPs nationwide.

The IP-Enabled Voice Communications and Public Safety Act of 2007 introduced in the Senate seeks to extend liability protection to nomadic VoIP providers and PSAPs interconnecting with them. The legislation is worded so that “whatever is required to do 911 gets protected and so does the service provider,” the NENA spokesman said.

“We’re very much interested in having that liability protection in place,” the NENA spokesman added. “It provides parity for wireless and wireline that’s already on the books.”

The idea of liability protection also has broad support from VoIP providers such as Vonage and Level 3 and from more traditional telcos such as Verizon. In addition to traditional phone service, Verizon offers nomadic VoIP under the VoiceWing brand.

Despite its broad support, however, liability protection legislation is by no means a shoe-in. Legislators may perceive that they have more pressing issues with which to contend, noted Seitz. “No one is against it,” he said. “It’s more a question of priorities.”

Whether out of concerns about liability, the lack of automatic location capability or both, some PSAP administrators currently are unwilling to let providers of nomadic VoIP service interconnect through the dedicated 911 network. That network automatically routes 911 calls to the appropriate PSAP based on the caller’s location and, if the PSAP supports enhanced 911, also delivers the caller’s address.

The NENA spokesman insisted that the number of PSAPs refusing to interconnect with nomadic VOIP providers is very low. “We don’t recommend not answering 911 calls,” the spokesman said.

Nevertheless, Seitz said Vonage has been unable to reach agreements to interconnect with PSAPs serving about 2.5% of its customer base. To serve those customers, Vonage operates its own emergency answering center, where operators try multiple administrative numbers to reach the appropriate PSAP when the customer dials 911. Also known as “lunch money” lines, administrative numbers are intended to give non-emergency callers a way to reach 911 personnel without going through the 911 system.

Other nomadic VoIP providers have been more cautious and have simply avoided offering service where they could not reach an agreement with the PSAP. AT&T, for example, recently cancelled it nomadic CallVantage service in such areas.

If enacted, Seitz believes the liability legislation would increase the number of PSAPs willing to interconnect with nomadic VoIP providers. He emphasized, however, that PSAP cooperation should not be dependent on that.

“The fact that some PSAPs won’t take 911 calls is a travesty,” he said.