Wireless Emergency Alerts

Wireless Emergency Alerts (WEA, formerly known as the Commercial Mobile Alert System (CMAS), and prior to that as the Personal Localized Alerting Network (PLAN)), is an alerting network in the United States designed to disseminate emergency alerts to mobile devices such as cell phones and pagers.

The Federal Communications Commission proposed and adopted the network structure, operational procedures and technical requirements in 2007 and 2008 in response to the Warning, Alert, and Response Network (WARN) Act passed by Congress in 2006, which allocated $106 million to fund the program. CMAS will allow federal agencies to accept and aggregate alerts from the President of the United States, the National Weather Service (NWS) and emergency operations centers, and send the alerts to participating wireless providers who will distribute the alerts to their customers with compatible devices via Cell Broadcast, a technology similar to SMS text messages that simultaneously delivers messages to all phones using a cell tower instead of individual recipients.

The government issues three types of alerts through this system:

When the alert is received, a sound is played if the ringer is on. On nearly all devices, the Emergency Broadcast System radio/TV attention signal sounds in a predetermined pattern.

The system is a collaborative effort between the Federal Emergency Management Agency (FEMA), the Department of Homeland Security Science and Technology Directorate (DHS S&T), the Alliance for Telecommunications Industry Solutions (ATIS), and the Telecommunications Industry Association (TIA),

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