Answering the wireless emergency call

In the January 2000 issue, I described all the wonderful innovations I foresaw in our future. This January, I describe a problem that some of this innovation is causing

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In the January 2000 issue, I described all the wonderful innovations I foresaw in our future. This January, I describe a problem that some of this innovation is causing.

"Johnny, call 911 and tell them to send an ambulance!" It sounds pretty simple. Johnny picks up the telephone, dials 911, and the ambulance is expected any moment. Only, Johnny is four years old and his mother is busy performing CPR on his little brother, whom she just pulled from the bottom of the backyard pool.

Throughout the U.S. and Canada, 911 is the universal emergency number for assistance during an emergency. When you dial 911, you are routed to a Public Safety Answering Point (PSAP), and most of the time a display tells the emergency dispatcher where you are calling from, even if you cannot verbally relay that information. That capability is known as enhanced 911, or E911.

It all began in 1957, when the National Association of Fire Chiefs recommended using a single number nationwide for reporting fires. And in 1967, the President's Commission on Law Enforcement and Administration of Justice recommended using a single number nationwide for reporting all emergencies. After much support, the President's Commission on Civil Disorders tasked the Federal Communications Commission (FCC) with finding a solution.

In November 1967, the FCC met with the American Telephone and Telegraph Company (AT&T), and the next year, AT&T announced that it would establish 911 as the emergency code throughout the United States. Why did AT&T choose 911? Because it was short, easy to remember, and had never been authorized as an office code, area code, or service code anywhere in the North American dialing plan.

As the new millennium began, 93% of the population living in 96% of the geographic U.S. was covered by some type of 911 service. And 95% of that coverage was enhanced 911.

But will the ambulance arrive in time? Will it arrive at all? That depends.

Thanks to all the emergency/rescue/police dramas on television, we all know that the ambulance is sent to the address where the telephone lives. But what if your telephone doesn't always live at the same address? Take, for example, the proliferation of wireless telephones today.

Improving wireless 911

Enter the FCC with a plan to improve wireless 911 services. According to the FCC, wireless carriers are to provide emergency dispatchers with information on the location from which a wireless call is being made. This is not just a "couple-of-mouse-clicks-and-they're-compliant" type of thing. Hence, wireless E911 is being implemented in two phases.

Phase I requires wireless carriers to deliver to the emergency dispatcher the telephone number of a wireless handset originating a 911 call, as well as the location of the cell site or base station receiving the 911 call. This provides only a rough indication of the caller's location.

Phase II requires carriers to deliver more specific latitude and longitude location information, known as Automatic Location Identification (ALI), to the dispatcher. And then we, the users, will all have to have E911-capable handsets. Yes, that means you may need a new cell phone to take advantage of the E911 service. To determine if your handset is E911-compliant, check with your service provider.

But what about the new voice over Internet Protocol (VoIP) telephones? Like wireless telephones, the telephone number of the IP telephone stays with the instrument. But unlike wireless telephones, there are no Phase I and Phase II requirements. So today, if the user moves a VoIP telephone and does not call the network administrator to report the move, there is no way to tell where the telephone is actually located. For example, let's say Johnny's mom, who is working from home this week, brought her VoIP telephone home from her office and connected it to her home network. When Johnny calls 911, an ambulance is promptly dispatched to mom's downtown office.

VoIP pushing 911's limits

This scenario is becoming more likely as telecommunications providers focus on converting telephone calls to data, and sending them around the world cheaply and efficiently. E911 is designed to work with the public switched telephone networks (PSTNs). Relatively few carriers operate these models of standardization and discipline. The Internet, however, is neither standardized nor disciplined. To set up personal long distance, one has only to buy a computer, install and configure a sound card and a microphone, install some software, and start making calls.

There is no question that VoIP benefits customers. But it also raises new and bewildering questions for public safety dispatchers, who are answering 911 calls that either carry no name, no address, or lack other location data that could help locate the caller. Worse yet, sometimes the dispatcher can receive information that sends the emergency vehicle off in the wrong direction.

Several manufacturers offer traditional-style telephones that connect to an IP network instead of a telephone wall outlet, can be conventionally dialed, and route voice calls as if they were being handled by the PSTN. Other manufacturers offer business-sized VoIP solutions that link extension to a central private branch exchange (PBX), and route calls to the PSTN or branch offices.

Several alternative long-distance carriers have announced that they will build IP networks to carry their customers' telephone traffic, or partner with companies that have IP network capacity. Even local exchange carriers are beginning to look at how they can better provide a broad range of voice, video, and data services to the residence. And the IP network may be the answer.

The problem: currently, there is no way of logging or identifying these IP nodes so they will display information when a user dials 911, and there are no VoIP directory services. Instead, each user group with VoIP capability must create and maintain its own list of IP addresses, and link them to names and locations. This, of course, assumes that users like Johnny's mom actually update the whereabouts of the telephone set, which is not likely. Why? Because there is no penalty, no calling in for activation. Unlike wireline services, the intelligence is in the telephone instrument, not on the cable. Sort of like a wireless instrument with a line cord to plug into a data network and no FCC requirements for ALI.

But I believe that relief is on the way. On May 1, 2000, President Clinton signed an executive order ending the government's intentional degradation of the global positioning system's (GPS) accuracy. President Clinton's order switched off the so-called "selective availability" (SA) feature of the GPS. SA continuously varied the accuracy of the civilian signal, effectively reducing its accuracy to 100 meters-not much help when you are trying to locate a heart attack victim in a high-rise area of a big city.

One-network solution

Because the civilian signal now has an accuracy of 20 meters or better, rest assured that many wireless carriers will select GPS to meet the FCC's E911 Phase II location requirements for wireless telephones. That means greater demand for the enabling chips, which means a lower cost per chip is likely. All this makes GPS-generated latitude and longitude for VoIP telephones a cost-effective solution to Johnny and his mom's problems. And yes, just like with wireless, that means you will need even newer VoIP telephones to take advantage of the E911 service.

By merging voice and data on one network, you could be managing only one network, not two. You could eliminate the PBX altogether and reduce the amount of cabling required in the work areas. VoIP will reduce the need for technicians to perform moves and adds, as people change offices within the network. Through the use of virtual private networks, VoIP can also support telecommuters and mobile workers.

Now, if we could just get a fire truck when we need one.

Donna Ballast is a communications analyst at The University of Texas at Austin and a BICSI registered communications distribution designer (rcdd). Questions can be sent to her at Cabling Installation & Maintenance or at PO Drawer 7580, The University of Texas, Austin, TX 78713; tel: (512) 471-0112, fax: (512) 471-8883, e-mail:

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