This is highly effective and passive system, which is capable of indicating any unauthorized intrusion from a long distance too, thus alerting the security against it.
Anintrusion systemis a device orsoftware applicationthat monitors network or system activities for malicious activities or policy violations and produces reports to a management station.
A basic intrusion detection system consists of motion sensors installed in strategic locations plus a siren and keypad.
This equipment is connected to a control panel which is usually located in your electrical room. The system is armed by the last person leaving the building, and disarmed by the first person coming in.