Emergency alerts using Wi-Fi networks

Could Wi-Fi networks be used for emergency alerts, like systems used by cellular, television, and radio? There’s some interest in doing so in IEEE Working Group 802.11.

Last week, 802.11’s Wireless Next Generation Standing Committee (WNG) saw a presentation from India’s Centre for Development of Telematics (C-DOT) on alerting technology it’s developed. It’s intended for users who have online access through Wi-Fi but no cellular connectivity. C-DOT notes there are over 43,000 villages in India without cellular service.

In C-DOT’s plan, when users are connected to Wi-Fi, an application on the user device conveys the emergency message.

When users aren’t connected to Wi-Fi, emergency messages are carried on an additional SSID that has, as its name, the alert (“Tornado warning”). The alert would thus appear in the device’s list of available Wi-Fi networks. Presumably, there’d be a mechanism for notifying the user when they’re not looking at that list. Access Points would need to be appropriately configured; C-DOT proposed that 802.11 determine whether any changes to the standard are necessary to do this.

Elsewhere in 802.11, Task Group bc has started the development of an amendment to the 802.11 standard for Enhanced Broadcast Service. The service would provide for more efficient distribution of local information, such as announcements or multi-media broadcast. Importantly for emergency alerts, the information could be received if there were no association (connection) between the Access Point and the user device. Emergency alerting wasn’t initially a priority in the Task Group, but there’s more interest now, in part because of the C-DOT proposal.

This is the first time I’ve seen this level of interest in emergency alerting in 802.11, but it’s still relatively little interest. If there’s nudging from other industry interests or policymakers, it could get traction. There’d be work required outside 802.11 to make an end-to-end emergency alert system.

Leave a Reply