Keepalive is a message, a signal sent from one device to another. The purpose is to verify that the link between the two is operating normally. The term comes from English, which means “to keep alive”. In our alarm systems, in the keepalive messages periodically exchanged between the sensors and the central, information on the battery level and signal level of each sensor is also sent. If any of the paired sensors do not respond or report that the battery or signal level is low, an event is generated to alert the monitoring. Having this information is essential so that the security system is always in perfect working order.