Clickability tracking pixel

Rush Hour

States hire companies to monitor traffic congestion by averaging cell phone signals on major roadways.

by / March 1, 2006
If cell phone signal traffic monitoring technology continues building steam, we all may be acting as traffic probes on the highway.

Missouri is the latest state to implement a program that measures traffic congestion on major roads based on the average time it takes drivers' cell phone signals to pass from cell tower to cell tower along those roads.

In With the New
Georgia, Maryland and Virginia have completed limited rollouts in select cities, but in February, Missouri became the first to carry out a statewide implementation, covering 5,500 miles of its busiest roads -- generally interstates and numbered routes.

"Missouri motorists will be better informed than anyone else in the country on which roads to use and how long the drive will take," said Pete Rahn, director of the Missouri Department of Transportation (MoDOT), in a statement.

At a cost of $6.2 million for two years, the cell phone system will provide traffic monitoring at a fraction of traditional method prices, according to MoDOT.

"With this new technology, we'll cover many more miles of highway without any new equipment," Rahn said.

MoDOT estimates that over the long run, cell phone traffic monitoring technology will cost less than one-sixth of traditional traffic detection costs.

The current methods of monitoring traffic on most U.S. highways are strategically placed "stick cameras" and embedded sensors in the pavement, which need regular replacement. The high price of those systems limits how many miles of highway they can track. By contrast, using cellular traffic monitoring technology, a state can constantly tap into a fleet of private vehicles to monitor traffic congestion for entire regions.

Cell phone companies divide cities into several zones, each encompassing roughly 10 square miles. When cell phones are turned on, the company can document the time a user passes from one cell tower to another.

Companies such as Delcan, Missouri's cellular traffic monitoring provider, pay cellular companies for the right to integrate their software with the companies' signal location databases. The software is programmed with a road map of each zone and uses algorithms to guess the route a driver takes and the driver's speed from tower to tower. The average speed of each route is continually recalculated to produce real-time traffic data -- states transmit this information to motorists through color-coded online graphics and electronic road signs.

Richard Mudge, vice president of Delcan, said the state would likely continue using stick cameras and embedded sensors in high-volume areas because the equipment can produce lane-by-lane information.

Maryland has used cellular traffic monitoring for the Baltimore metropolitan area for more than one year. The Maryland Department of Transportation didn't spend a penny of its own money on the project. Maryland used $1.9 million of its allocated funds from the Federal Highway Administration. The state normally would have needed to contribute matching funds to the project to use the federal money, but Delcan made up the difference.

Flexible Privacy
Cell phone signal traffic monitoring technology has spurred criticism from some privacy advocates worried that the technology will lead to normalizing a surveillance infrastructure capable of tracking our every footstep.

Mudge said nobody involved in the project had any interest in, or use for, tracking individuals. He said the software calculating traffic congestion in the cellular companies' databases keeps a cell phone user's identity on the cellular company's side of the firewall, where it is used for billing purposes.

"We don't need it. We don't want it. They wouldn't want to give it to us anyway," Mudge said. "If, for some reason, Maryland came to us and said, 'We'd like to know who was speeding on I-95 yesterday at 3 p.m. -- tell us,' we [wouldn't] know. All of us are concerned about privacy, but this is not the place to be worried about it."

Kevin Bankston, staff attorney for the Electronic Frontier Foundation, a privacy advocacy group, said cellular companies' involvement with the software violates a federal statute prohibiting them from using devices for routing, addressing or signaling information about an electronic communication for purposes other than meeting the inherent needs of the company -- needs like billing customers.

Bankston said the law provides no exception for cellular providers to sell access to their system for the installation of such a device for monitoring traffic.

"There is a simple solution to this, which is [for cellular companies] to get customer consent, and give the customer a choice -- a choice that they have by law -- to decide whether they want their phone and wireless location information used for this purpose," Bankston said. "It's clear that the companies are not doing that, and indeed, most of the phone companies are trying to avoid any direct statements about their involvement in this."

I See You
The most dramatic privacy concerns encompass what the government or private sector might discover with cell phone signals, and how they will use that information in the future.

If your cell phone is turned on, your cellular provider knows where you are within 10 square miles -- the general area of a cell. Some phones know, and eventually all will, where you are within 50 to 300 meters because of FCC rules forcing all cellular providers to install global positioning system units in their cell phones.

This enables emergency 911 operators to pinpoint a caller's location. Law enforcement has access to this data with a search warrant -- often one granted without probable cause, according to Bankston, but magistrate judges are trying to rectify the problem.

"The government, based on a completely unsupported argument, has apparently routinely successfully been getting magistrate judges to sign -- in secret proceedings -- surveillance orders forcing the phone company to allow the government to engage in real-time surveillance of people's location using their cell phone," said Bankston. "And these orders were not based on probable cause.

"This misrepresentation of the law has been possible because these proceedings are secret -- there is no adversarial process -- no one to call them on their bull," Bankston continued. "And typically the government isn't required to brief anything, they just hand the judge these surveillance applications, and they are signed."

Courts recently denied such warrant requests in New York, Maryland and Texas.

"We're seeing a magistrate judge revolt across the country," Bankston said.

Vendors that provide cellular traffic monitoring services say that cooperating cell phone companies vigorously insist that only 911 operators and warrant-waving law enforcement get access to their customers' personal location data. Time will reveal, however, whether they can resist the lure of less altruistic third parties.

"Marketers are very interested in this information," Bankston said. "The ability to market based on your location is a very, very valuable thing that many people are working toward."

The U.S. Department of Justice was contacted by Government Technology regarding the privacy aspect, but did not return repeated telephone calls.

Can We Handle It?
Philip Tarnoff, director of the Maryland Center for Advanced Transportation Technology, said the potential for privacy violations is nothing new to modern traffic management.

"There are so many devices we use in [the traffic] business that have that potential," Tarnoff said, explaining that popular methods, such as closed-circuit TV traffic monitoring and toll tag reading technology, also present privacy challenges -- challenges our society can handle.

A system in the metropolitan New York area called Transcom's System for Managing Incidents and Traffic (TRANSMIT) uses sensors located one and a half miles apart along major roadways to tracking vehicles equipped with toll tags -- each containing a user identity number. Upon reading the toll tag, the tracking system immediately scrambles its identity number and averages its traffic information with that of others.

"That system has been in operation for close to 10 years, and it's got exactly the same potential for violation of privacy that this system [cellular traffic monitoring technology] does," Tarnoff said.

The privacy predictions being made about cellular traffic monitoring were also voiced about TRANSMIT, but no abuses ever materialized, he added.

It's worth noting that cell phone companies will be able to track us where we go, regardless of whether that information is used for monitoring traffic congestion. One could argue that making the potential for abuse prevalent inevitably makes it likelier to happen.

Some might say society eventually slides down every slippery slope when given the opportunity. But most Americans battle traffic congestion daily. It is also fair to ask whether we should avoid something capable of improving that situation because we don't trust ourselves to handle the ethics involved.

Looking for the latest gov tech news as it happens? Subscribe to GT newsletters.

Andy Opsahl

Andy Opsahl is a former staff writer and features editor for Government Technology magazine.

Platforms & Programs