SECURITY SYSTEM

摘要

PROBLEM TO BE SOLVED: To establish a security system where a communication unit can communicate with a monitoring center even in an emergency situation while curbing increase in a cost for the communication unit.SOLUTION: One communication unit 3 comprises: communication state confirmation means 31 which confirms whether or not external communication means 5 can communicate with a monitoring center 4; proxy request transmission means 32 which transmits proxy communication request signal p requesting another communication unit 3 to transmit communication information d to the monitoring center 4 in place of the one communication unit 3 when the communication state confirmation means 31 confirms that the external communication means 5 cannot communicate with the monitoring center 4; and proxy transmission means 33 which transmits the communication information d of the other communication unit 3 to the monitoring center 4 in place of the other communication unit 3 when the proxy communication request signal p from the other communication unit 3 is received and the communication state confirmation means 31 of the one communication unit 3 confirms that the external communication means 5 can communicate with the monitoring center 4.