Cell Broadcast is a cellular based system that instantly broadcasts voice, data, or multimedia content to a large number of people specific to a geographical area. This system uses a feature already built into most cell phones to alert users to impending disasters, such as the tsunami that devastated Southeast Asia.
Because the cell broadcast alert system is geographically based, only the people in the designated affected area receive the alert. The system notifies the phone subscriber that a text message is being displayed. Unlike a voice message, everyone carrying an EAS-equipped phone in the desired communication region receives the alert at once without queuing delays. The wireless network uses a “broadcast control channel” instead of a “voice channel” or an individual "signaling channel" per subscriber. In this way, millions of subscribers may be reached simultaneously without overloading the network, as has happened in recent emergency situations occurring internationally.
Cell broadcasting is an existing, but primarily unused, capability of GSM and CDMA digital phone networks that can transmit uniform text alerts. It is different from SMS in that the broadcast relays the message indiscriminately to every phone in a cell tower's receiving area, without having to identify and locate individual phone numbers. The area can range from the relatively small area covered by a single cell (or pico-cell) to an entire network, which can cover a large geographical area.
Why Deploy Cell Broadcast Now?
Recent natural disasters like hurricanes Katrina and Rita,
the December 2004 tsunami, and man-made threats result in thousands of innocent
people being put at risk every year. Imagine if Cell Broadcasting became an
integral part of every city's Amber Alert Program. According to the National
Center for Missing & Exploited Children, 74 percent of kidnapped children
who are murdered are dead within three hours of the abduction. With Cell
Broadcasting, pictures of children and maps could be instantly disseminated to
cell phones in the affected area quickly and efficiently offering a practical
solution in times of crisis.