WiFi on the highway: UMass project in race to provide Internet access to motorists
UMass project in race to provide Internet access to motorists
Saturday, October 18, 20081
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AMHERST - It's not clear who will supply the first mass mobile wireless network - a system that will make surfing the Web while cruising in the car possible. But University of Massachusetts researchers were in the game early and are players in this high-tech race.
Through a partnership with Microsoft, UMass is developing Vi-Fi, a system of seamless wireless Internet for use in vehicles.
This method of mobile Internet connection is different from Wi-Fi, the technology that gave birth to "hotspots" and makes online surfing possible in cafes and homes without wires.
But today's Wi-Fi is unable to provide continuous, high-quality Internet access for people on the move. Vi-Fi's creators say they can deliver an Internet connection so strong and steady that people can surf the Web or communicate through VoIP, a phone connection over an Internet network, with the same speed they can from home computers.
The key to Vi-Fi's mastery of the online connection is the way it relays information, said Aruna Balasubramanian, a UMass doctoral candidate and lead researcher.
While Wi-Fi uses a single point at a time to connect to the Internet, Vi-Fi taps into multiple Web signals, thus providing a stronger and lasting connection, even when a person is traveling.
UMass and Microsoft researchers said they see Vi-Fi being used by car passengers to connect their laptops and smart phones to the Internet. It would also enable other devices inside vehicles, such as satellite navigation units, to download information including maps, directions and traffic conditions.
"People should expect the Internet to be a utility they can take with them," said Brian N. Levine, a UMass computer science professor. "It will be just like electricity."
Levine said he sees the technology benefiting municipal and emergency service providers such as police and firefighters, who now mostly communicate by radio, a communication mode that can be inhibited by the limits of radio frequency.
Research into the technology is ongoing at the Massachusetts Institute of Technology, Rutgers University and University College London.
"It's really validating to see all these other universities looking at this network," said Levine. "It's nice when people join what you're doing."
Timeline unclear
Vi-Fi is in the process of being patented, said Balasubramanian, but she is unsure how soon people may be using it in their cars.
The sprint to the market is still on, and it's unclear how infrastructure necessary to operate any of the mobile wireless networks will be constructed - and by whom.
As is evident by a number of failed municipal Wi-Fi plans (including those in Boston and Chicago), finding a private organization to invest in municipal start-up infrastructure can be difficult.
Vi-Fi hopes to bypass the problem of initial investments by building on established Internet access points - free hotspots provided by municipalities, homes and cafes, for example - in addition to those that may be required for less densely populated areas.
"It's hard to speculate on what will be used in wireless technology," Balasubramanian said. "I don't know if one will dominate or if many will coexist in the foreseeable future."
Origins of UMass work
The seeds of Vi-Fi research at UMass were planted two years ago when the university - through grants of more than $1.5 million from the National Science Foundation and the Defense Advanced Research Projects Agency - built DieselNet, a network of buses connected to the Internet through a mesh network.
Think of a mesh network as a field of open, adjacent umbrellas with each cane acting as the Internet signal's source, and the cloth shield symbolizing that signal's reach.
Through Wi-Fi, and originally through DieselNet, Internet signals jump from umbrella to umbrella, or access points, handing off Internet connection as the Web surfer moves.
Downtown Amherst, which offers free wireless Internet through the DieselNet project, has at least 24 Internet access points.
This signal handoff often leads to Internet disruption, a frozen screen, or a dropped signal.
Balasubramanian said it is obvious that people would like to be connected to the Internet as they go about their days. Take Apple's iPhone, for example, she said, noting the phone's wireless capabilities.
She believes the current model for supplying mobile Internet access and Internet voice communication is inadequate.
"We wanted to satisfy the demand for mobile users. That is the genesis of this project," Balasubramanian said. "People don't want to wait when they're online - they want it to work immediately. They want quality."
So Balasubramanian decided to tackle the nemesis of quality Internet communications: VoIP, or Voice over Internet Protocol. Unlike email and Web browsing, which are easier for programmers to supply because the applications do not demand high-speed seamless Internet, a glitch in an online connection for a VoIP conversation leads to dropped calls and conversations full of static.
"VoIP is one of the hardest (applications) to support," Levine said. "If you're going to tackle (mobile Internet networks) then you probably have to address VoIP."
Others working on the project are UMass computer science professor Arun Venkataramani, Microsoft researcher Ratul Mahajan and University of Washington computer science professor John Zahorjan.
Tapping multiple access points
To deploy a seamless network of wireless Internet connectivity, researchers devised an information relay system that draws signals from various Internet points, as opposed to the single connection point that Wi-Fi uses.
Venkataramani described Vi-Fi's multiple connections by conjuring up images of comic book superhero Spiderman swinging from building to building in New York City.
"Imagine Spiderman," he said, "swinging from buildings. He releases a web rope that is very fragile, one at a time, releasing it as he goes. So if one breaks he would fall. But imagine if he could hang on multiple connections. If one broke, he would not fall."
Vi-Fi receives signals from a number of open access points, but selects one as the base station or "anchor," Mahajan explained.
As the Vi-Fi user is logged online, the information being exchanged between the user and the anchor is being overheard, in a sense, by the other "auxiliary" Internet access points to which the Vi-Fi user is simultaneously connected.
For each information transfer between user and anchor, auxiliary access points are deciding among themselves, through an algorithm, whether information is reaching the Vi-Fi user. If the information did not reach the user, the data is immediately sent by an auxiliary point. This transfer is designed to be seamless.
"In summary, today, Wi-Fi clients communicate with only (one) base station at a time," Mahajan said, "which leads to frequent connectivity disruptions. Vi-Fi extends Wi-Fi to enable clients to leverage multiple nearby base stations to reduce connectivity disruptions and improve application performance."
First test
Vi-Fi was first tested at the Microsoft campus in Seattle, Wash., in 2007. For the initial experiment, people sat on Microsoft shuttles with laptops and tried to log on to the Web. The experiment was successfully replicated in Amherst.
Balasubramanian said she does not foresee the installation of infrastructure needed to support Vi-Fi as being an inhibitor to the technology's widespread adoption or application. Much of that equipment has already been installed and continues to expand, she said referring to Wi-Fi access points.
"What I suspect is that it will take a small change to computer Wi-Fi to do this," Balasubramanian said.
Kristin Palpini can be reached at kpalpini@gazettenet.com.
