Idaho Police Department Installs WLAN Gear

Scott Haug, a patrol lieutenant on the police force in Post Falls, Idaho, decided last year that he wanted to give officers access to the same kind of applications and information they might use at the station on their desktop computers, while they were out patroling the city in their cruisers.

Post Falls is about 25 miles east of Spokane, Wash., in the Idaho panhandle. Its police department, like many other public safety agencies in the country, had relied primarily on voice radio for communications between its dispatch center and patrol cars, an inefficient and error-prone system.

Although it isn't his primary role, Haug says he took on the wireless network job because of his interest in computers and communications, describing himself as a self-taught computer hobbyist.

Haug's plan was to provide patrol officers with e-mail and direct access to the FBI's National Crime Information Center database and give headquarters the ability to rapidly transmit photos of crime suspects to the patrol cars. Haug says he spent close to a year researching wireless options that could meet the department's needs and finally settled on what he calls "nontraditional" use of 802.11b wireless LAN systems.

The department examined but rejected high-speed cellular data service because even with advanced service, the cellular carriers offered data rates measured in kilobits per second compared with 802.11b networks that promised raw data rates of 11Mbit/sec., Haug says.

Backed by a grant of $160,000 from the Department of Justice and additional funding of $40,000 from the city, Haug built a wireless network that gave patrol officers the same kind of connectivity and access to applications they would have at the station over the 60 square miles of the city. The network went live earlier this year.

Adapting 802.11b Wi-Fi WLAN gear -- which has a range of about 300 feet -- to serve as a WAN covering such a large area proved a challenge, Haug says. The network required installation of an infrastructure of 22 Wi-Fi access points from Proxim Corp. in Sunnyvale, Calif. These access points are interconnected to one another and police headquarters by five 11Mbit/sec. backbone links using Proxim Orinoco outdoor routers. They operate in the same 2.4-GHz frequency bands as the access points.

The network, which includes access points on 4,500 mountains, helped ensure coverage over and around hills and trees, which the city has in generous quantities.

Despite this extensive infrastructure, Haug says the network manages only 90% coverage. When officers hit a dead spot, they have to move their cars. "You're never going to get 100% coverage using 2.4 MHz" in a geographically challenging environment such as Post Falls, Haug says.

Each of the city's 22 patrol cars now carries a model 5350 laptop computer from Gateway Inc. in Poway, Calif., equipped with a Proxim Wi-Fi access card wired to an antenna on the roof that communicates with the access points.

This citywide, high-speed network gives patrol officers instant access to the FBI criminal database without having to call a dispatcher, Haug says. When the officers make a traffic stop and need to check a driver's license, the system can zip them into the state's license database. This saves patrol officers a minute or more per traffic stop, he says.

The in-car computer can also access wireless video cameras installed at potential crime spots around the city, "allowing the officers to be almost in two places at one time," Haug says.

Post Falls designed security into the system from the start, Haug says. The system uses 128-bit encryption, and the service set identifier broadcast was turned off by access points to thwart hobbyists who attempt to sniff out Wi-Fi networks using easily available online tools such as NetStumbler.

Post Falls has also decided to use a dynamic key system on the access points and clients that changes every 15 minutes; another way to protect against intruders, Haug says. Jeff Orr, product marketing manager at Proxim's WAN division, says the Orinoco outdoor routers used in the backbone provide added security by using a hard-to-crack proprietary encryption protocol.

Haug says he plans to use the network to extend the police switchboard directly to the cars, through the use of what he calls "soft-phone" versions of voice-over-IP WLAN phones. He says he plans to install voice-over-IP software on the patrol car computers to allow officers to talk over the soft phones via headsets.

Alan Reiter, an analyst at Wireless Internet & Mobile Computing in Chevy Chase, Md., says the Post Falls system illustrates that Wi-Fi has uses far beyond its original design as a purely local-area technology. "We have just started to open up the envelope on Wi-Fi," Reiter says. The Post Falls network shows that in some cases Wi-Fi can provide higher dates at a lower cost and better coverage than wide-area cellular data networks.

The Post Falls Police Department's unconventional WLAN system has already proved itself by ensuring that patrol officers have access to all the information they need "at their fingertips," Haug says. A better-informed officer, he says, makes for a safer city.

Copyright © 2003 IDG Communications, Inc.

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