Newbury Networks has launched a network appliance that collects data from wireless LAN access points and clients, computes their location and then passes that information to various applications.

The Newbury Location Appliance is intended to be a kind of built-in enterprise tracking service, supporting mobile applications such as asset tracking, security and network provisioning. It competes directly with the only product of its type, the Cisco Wireless Location Appliance 2710 .

Most wireless location applications are focused on a specific application, such as tracking portable manufacturing equipment or hospital patients . In some case, a separate network of wireless access points or sensors have to be installed.

But some enterprises find the benefits of wireless location services so compelling, they're creating their own infrastructure, as The Boeing Company has done .

Newbury is targeting such companies with its appliance, which is a rack-mounted device that can read signal strength data from an existing 802.11 WLAN. Newbury's algorithms and software calculate the location of both access points and client wireless devices, which can include 802.11-based radio tags used for asset tracking. This data, along the device's MAC address, is then made available via Java APIs or web services interfaces to applications from Newbury or third parties, or to custom-built applications.

One of the largest general hospitals in The Netherlands, Medisch Centrum Alkmaar (MCA), based about 30 miles north of Amsterdam, has been testing the Newbury product, funneling patient location data into a program called the Electronic Nurse File, says Martin van der Meer, information advisor with MCA. Nurses with notebooks or PDAs now get a short list of their patients in the area. They can select a patient and then access the relevant medical records, rather than having to separately scan a barcode on the patient's wrist.

Van der Meer says the ENF application integrated smoothly with the Newbury appliance, as the appliance did with the hospital's Trapeze Networks-based WLANs. The appliance has run reliably and has been simple to manage, he reports.

Newbury's software, like some other location products, uses a reading called relative signal strength indicator (RSSI), which WLAN access points use to report the strength of the signal used to send the access point a given data packet.

In Newbury's case, the server software collects RSSI data from a group of neighbouring access points to create a pattern, or fingerprint, for each wireless device. This technique, which Newbury calls "server-side pattern matching," creates a real-time pattern that is compared to a database of stored access point patterns to pinpoint a radio's location.

The Newbury appliance can track any 802.11-based radio, and captures and pinpoints the radio within 20 to 30 seconds of the radio going live, according to executives. The company says that 99 percent of the time the Newbury software locates the radio within a 30-feet diameter circle. The appliance can be configured to reduce the diameter to about 9 feet, thereby increasing the accuracy. But the error rate increases: the radio will be found within that smaller circle 95 percent of the time.

MCA needed pretty accurate locations: patients had to be located in a given room. The Newbury appliance has generally been able to deliver that, van der Meer says. "It is not always possible for 100 percent [of the time]," he says. "The accuracy is dependent on the wall thickness and the number and location of access points. [But] the accuracy is much better than the 10-meter [30-foot] circle given by Newbury."

Each appliance can track up to 2,000 wireless devices at the same time, says Brian Wangeren, Newbury's vice president of business development. A set of visual screens give users a real-time view of radio locations and movement.

To start with, the appliance works with the battery of Newbury's own applications, including: WiFi Watchdog for WLAN security, WiFi Workplace for managing the radio spectrum, and Active Asset, a real-time asset tracking program introduced earlier this year.

The recently announced development toolkit, Newbury Presence Platform, can be used by software developers to tie new or existing applications into the Newbury appliance.

"We're talking with various third parties to enable location for their applications and to do so across various WLAN infrastructures," says Wangeren. He wouldn't name the other companies, but agreements will be announced once they're finalised.