Can Wi-Fi Rescue VOIP 911?

By Carol Ellison  |  Posted 2005-05-27 Print this article Print

Opinion: Wi-Fi positioning systems are starting to emerge. Able to detect the position of a device with a Wi-Fi chip, they may be the Rx for the VOIP services' problems with E911.

What is an FCC ruling if not a business opportunity for some company? With every decision that marks a sea change on the telecom horizon, theres usually a technology solution to address it. Last weeks order that Internet telephone carriers provide full 911 emergency calling services, possibly as early as October, hit a rapidly growing VOIP (voice over IP) industry that wasnt quite prepared for it. Click here for details on the FCCs order.
Pinpointing the exact origin of a VOIP call can be difficult to impossible using current technologies since customers can choose distant area codes and use the service when theyre away from home.
Skyhook Wireless was staffing up for the imminent rollout of its technology just as the FCC delivered its ruling. Barely a business day had passed after the FCC made its pronouncement when Skyhook began positioning itself for its upcoming product rollout by bringing two key startup specialists into its fold. Shikhar Ghosh, whose e-commerce software company, Open Market, which he co-founded in the 1990s, changed how we think about doing business, came on board as chairman. Dr. Kaveh Pahlavan, a professor and director of the Center for Wireless Information Network Studies at Worcester Polytechnic Institute in Massachusetts, joined the company as chief technical advisor. Pahlavan is a specialist in location-aware broadband networks. Right now, his focus—like Skyhooks—is on Wi-Fi. Skyhooks positioning technology is somewhat similar to what you find in GPS, except that GPS triangulates against satellites, using them as reference points, and Wi-Fi uses other Wi-Fi devices. "Based on what a device can see from wherever it is, we can tell you with some degree of precision where you are located. What we do is fill in the blanks where GPS doesnt work very well," Ghosh said. The difference kicks in on distances. GPS works best in open areas where signals have a direct path to the satellite and doesnt work well—or doesnt work at all—in areas where there is no line-of-sight to the satellite. Wi-Fi, on the other hand, is a short-range technology that works best when the signal bounces off of other nearby devices and fails in large open areas where a single device operates at a great distance from its neighbor. Since the population of Wi-Fi devices in cities is dense and getting denser, it promises to deliver positioning in areas where GPS traditionally has had difficulty. But once you get past that basic concept, things start getting complex. A device might be in a basement where the signal is weak or inaccessible. Or it might be positioned near glass or water where the signal is distorted. Wi-Fi itself complicates the task because its signal pattern does not radiate out from devices in perfect circles. Ghosh likens the shape to that of an amoeba. Add to that the fact that youre talking about a mobile technology and the challenge becomes even greater. According to Ghosh, five to seven percent of existing Wi-Fi devices are mobile at any one time. "All of a sudden, the one we thought was here is no longer here. So you have to compensate for that in a whole variety of different ways," he said. Click here for Larry Seltzers analysis of the technical challenges in providing E911 service over VOIP. Skyhook has been working on the challenge for about 14 months now, looking to carve a niche alongside GPS in the positioning market and talking to GPS firms about selling combined solutions. Other key markets were those that need or want positioning but dont have the GPS infrastructure to deliver it. In the enterprise space, think asset recovery; using Skyhooks location-aware technology, all those laptops that walked away, all those handhelds left on trains and in taxis, could find their way home. On the consumer side, think of something like a location-aware digital camera that records the location where a photo is shot along with the photo. "All handhelds typically have Wi-Fi but no GPS built-in. You can have location at a very small cost. The infrastructure, which is a very small chip, is already built-in," Ghosh said. With Wi-Fi positioning, suddenly things like location-aware advertising on passing laptops become realities. So does location-aware VOIP service that can identify the position of nomadic users during times of emergency. On the face of things, Skyhook Wireless looks to be in a position thats not too different from where Ghoshs Open Market found itself in the early days of Internet commerce—at the crest of a wave thats just about to break over the shore of a beckoning industry. Just how big that wave promises to be depends on Skyhooks upcoming field trials of its positioning algorithms, the number of vendors impressed by them and whatever the FCC actually does to force position-identification of VOIP-enabled devices. "The cellular carriers have had the same mandate about five years now and every year they get a waiver from the FCC saying the technology is not quite there. At this point we think the technology is there," Ghosh said. "You dont have to have a GPS device. You can have anything thats Wi-Fi-enabled. The advantage is you already have laptops out there with Wi-Fi in them." Check out eWEEK.coms for the latest news, reviews and analysis on mobile and wireless computing.
Carol Ellison is editor of's Mobile & Wireless Topic Center. She has authored whitepapers on wireless computing (two on network security–,Securing Wi-Fi Wireless Networks with Today's Technologies, Wi-Fi Protected Access: Strong, Standards-based Interoperable Security for Today's Wi-Fi Networks, and Wi-Fi Public Access: Enabling the future with public wireless networks.

Ms. Ellison served in senior and executive editorial positions for Ziff Davis Media and CMP Media. As an executive editor at Ziff Davis Media, she launched the networking track of The IT Insider Series, a newsletter/conference/Web site offering targeted to chief information officers and corporate directors of information technology. As senior editor at CMP Media's VARBusiness, she launched the Web site, VARBusiness University, an online professional resource center for value-added resellers of information technology.

Ms. Ellison has chaired numerous industry panels and has been quoted as a networking and educational technology expert in The New York Times, Newsday, The Los Angeles Times and The Wall Street Journal, National Public Radio's All Things Considered, CNN Headline News, WNBC and CNN/FN, as well as local and regional Comcast and Cablevision reports. Her articles have appeared in most major hi-tech publications and numerous newspapers and magazines, including The Washington Post and The Christian Science Monitor.

Submit a Comment

Loading Comments...
Manage your Newsletters: Login   Register My Newsletters

Rocket Fuel