A security network for a building using at least one RFID reader to communicate with at least one RFID transponder to provide the radio link between each of a number of openings and a control function capable of causing an alert in the event of an intrusion. A gateway provides an interface between the security network and various external networks. The control function can be located in either or both of the RFID reader and the gateway. The RFID transponder is connected to an intrusion sensor. The gateway can communicate with the RFID reader using active RF communications, power-line communications protocol, or hardwire connection. The RFID transponder can contain an energy store. The RFID reader contains means for transferring power to an RFID transponder for the purpose of charging any energy store. The security network can contain more than one RFID reader.