The correct answer is Perimeter Intrusion Detection System (PIDS). In a circular, the Bureau of Civil Aviation Security (BCAS) said that all "hyper-sensitive" airports in the country will have to install a Perimeter Intrusion Detection System (PIDS) by December 2023. PIDS is a sensor that helps alert security agencies of any intrusion through the boundary walls of the airport. The BCAS is the apex body of aviation security in the country. Additional Information?The Bureau of Civil Aviation Security is an attached office of the Ministry of Civil Aviation. It is the regulatory authority for civil aviation security in India. It is headed by an officer of the rank of Director general of Police and is designated as Director General of Bureau of Civil Aviation Security. It was founded in January 1978.