By Wayne Rash
Opinion: While many hurdles remain with trying to pinpoint the caller's location, Enhanced 911 services are starting to become available for VOIP users.
There's a probably apocryphal story that floats around the VOIP community when the subject of emergency phone calls comes up. In that story, an office worker, some say a Cisco engineer, has a heart attack and dials 911. Paramedics arrive, but no one has any idea where the victim is. He dies before he's found.
It's a scary story about the problems of providing location information to emergency service providers when callers are using VOIP (voice over IP) telephones, especially in a corporate environment. And in fact, there is just such a risk. With a number of telephone technologies, location information is not readily apparent. Wireless phones, for example, suffered exactly the same problem until the federal government mandated the ability to locate callers in an emergency.
Wired phone users haven't usually had this problem because the phone company keeps track of the address where each phone is located, as long as the phone is theirs and is attached to their phone lines.
When a user of a wired phone calls 911, their phone number is included with the call, and that in turn provides the address through a database maintained by the phone company. This system works fairly well, despite the occasional delays in database updates when people add a phone or move to a new address.
Things change when you're not connected to the phone company's lines. Cell phone users, for example, are connected to their wireless provider. Until recently, the best the wireless company could do was to have a general idea of the area of the caller, accurate perhaps to several square miles. Now, with more accurate location being mandated, phones can be located using other means, including GPS (Global Positioning System) receivers embedded in many phones.
But when you get to private phone systems, there's a problem. Even if your phone delivers a phone number, there's no reason to believe it's tied to a location. Even with analog PBX (Private Branch Exchange) phones, it's not uncommon for the phone number that's reported to the receiving party to be either an invented number or the main number for the entire company or agency.
This problem is not restricted to IP phones, and it's not really related to phone technology at all, but rather to choices made by phone system owners. In many cases, phones don't even have actual phone numbers-simply extensions from the company PBX.
Since most corporate VOIP systems are based on IP PBX equipment, it's no surprise that getting location information is a challenge. But as it happens, that challenge is being met.
According to Tim Lorello, vice president at Annapolis, Md.-based TeleCommunication Systems, the company that provides the vast majority of E911 service in the United States, help is already on the way.
Lorello said network service providers are already making it possible for users with fixed locations to enter their location manually into the database that provides information to emergency services. He said the next step will be to equip VOIP phones with the GPS receivers already in use in cell phones. He said that when this happens, the E911 systems will be able to use that information immediately.
The other challenges Lorello pointed out are knowing which emergency service provider needs to be called, and then delivering the call to the right place. "Today, that call routing occurs to administrative line," Lorello said. This can delay emergency response and can cause confusion. Having location information included with the call will make sure that the call goes to the right place the first time, he said.
Lisa Pierce, a vice president at Forrester Research, says the current efforts to make VOIP phones compatible with E911 may make them work better for emergency calls than today's analog phones do. However, she worries that expectations will rise faster than the technology.
"There will be false expectations while this is being built," Pierce said. "This will give the technology a bad name for a period of time while things are getting coordinated."
Pierce said a major factor will be how well network providers and emergency service providers work together during that time to minimize problems.
In the meantime, Pierce noted that one cell phone manufacturer, Motorola, has also announced a wireless VOIP phone. I hope that one will include the GPS receiver that the company already builds into its other wireless phones.
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