Intrusion detection system (IDS) is a type of physical security system which helps in identifying any security breach,protocol violation or a misuse. Intrusion detection technology only handles a single aspect of security, making it unsuitable to be considered as a complete defence. However, we do believe it can play a significant role in the overall security architecture, when combined with video surveillance, access control, identification systems, security personnel and other physical security systems, to offer a more dependable and comprehensive security infrastructure.