Cell Broadcast

Cell Broadcast/Cell Information (CB) messaging is a mobile technology feature defined by the ETSI’s GSM committee and is part of the GSM standard. It is also known as Short Message Service-Cell Broadcast. (SMS-CB).

Cell Broadcast is designed for simultaneous delivery to multiple users in a specified area. Whereas the Short Message Service-Point to Point (SMS-PP) is a one-to-one and one-to-a-few service (requires multiple SMS messages, as each message can only carry one phone number), Cell Broadcast is a one-to-many geographically focused messaging service. Cell Broadcast messaging is also supported by UMTS.

Cell Broadcast messaging was technologically demonstrated in Paris for the first time in 1997. Some mobile operators use Cell Broadcast for communicating the area code of the antenna cell to the mobile user (via channel 050), for nationwide or citywide alerting, weather reports, mass messaging, location-based news, etc. Not all operators have the Cell Broadcast messaging function activated in their network yet, and many handsets do not have the capability to support cell broadcast.

Cell Broadcast is a technology that allows a text or binary message to be defined and distributed to all mobile terminals connected to a set of cells. Whereas SMS messages are sent point-to-point, Cell Broadcast messages are sent point-to-area.

Thus, one Cell Broadcast message can reach a huge number of terminals at once. In other words, Cell Broadcast messages are directed to radio cells, rather than to a specific terminal. A Cell Broadcast message is an unconfirmed push service, meaning that the originator of the message does not know who has received the message, allowing for services based on anonymity. Mobile telephone user manuals describe how the user can switch the receiving of Cell Broadcast messages on or off.

Cell Broadcast is not as affected by traffic load; therefore, it may be usable during a disaster when load spikes (mass call events) tend to crash networks, as the 7 July 2005 London bombings showed. Another example was during the Tsunami catastrophe in Asia. Dialog GSM, an operator in Sri Lanka was able to provide ongoing emergency information to its subscribers, to warn of incoming waves, to give news updates, to direct people to supply and distribution centres, and even to arrange donation collections using Celltick's Cell Broadcast Center, based on Cell Broadcast Technology.

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