Campus Safety

New API Helps Admins Locate E911 Callers

• By Dian Schaffhauser
• 04/29/10

Two companies are working together to deliver a WiFi emergency call location service for campuses. Aruba Networks, which develops wireless networking gear, and RedSky Technologies, which develops "enhanced 911" (E911) applications, have introduced a new application programming interface (API) that allows E911 Manager to be updated in real-time with the location of every voice-capable device on the wireless LAN.

As the companies pointed out, pinpointing the location of an E911 call originating from a WiFi phone is challenging because the user could be on the move. The new solution locates WiFi phones as they originate E911 calls, allowing first responders to be dispatched to the correct address, building, or floor.

The typical route to obtain location data has been to use IP parsing, which translates the IP address of the closest Ethernet switch or router into a physical location, which can then be relayed to first responders. The problem with IP parsing is that it's only as good as the assignment of subnets to each physical area. The E911 caller may be a considerable distance from the network gear.

"Emergency location identification is a key feature sought by all institutions migrating from wired Ethernet to WiFi access, and we believe Aruba offers the only solution with this important feature for all voice clients, both local and remote," said Peter Thornycroft, Aruba's wireless applications manager. "The solution works over our campus wireless LANs and virtual branch network solutions for remote offices and teleworkers--and doesn't require any hardware changes to the network."

With the API implementation, the location process works this way:

1. Aruba's wireless LAN sends real-time location updates to RedSky E911 Manager as voice clients move around on the network. The caller's location is triangulated by processing signal strength and other data from nearby Aruba access points and forwarded to RedSky.

2. RedSky's E911 Manager updates internal, external, and IP-PBX databases with the location of the
clients.

3. When a voice client dials 911, E911 Manager provides instructions to the IP-PBX to route the call and notifies internal security personnel with location information derived from floor plans of the facility.

4. The E911 dispatcher receives the emergency voice call and location updates in real-time and is then responsible for directing first responders to the correct address, building, and floor.