What is GPS spoofing, interference signals reported at Delhi, Mumbai, Bengaluru airports

THe authorities on mon confirmed that several airports, including new delhi, bombay and Bengaluru, saw GPS spoofing signals endure month, but said there was no impact on flight operations.Addressing the Rajya Sabha, Civil Aviation Minister Ram Mohan Naidu detailed incidents of “spoofed” flights in vicinity of the Delhi airport, and said the Wireless Monitoring Organisation (WMO) had been tasked with tracing its source."Some flights reported GPS spoofing in the vicinity of IGIA, New Delhi while using GPS based landing procedures, while approaching on RWY (runway) 10. Contingency procedures were used for GPS spoofed flights approaching to RWY 10," Naidu said, in response to a query by MP Niranjan Reddy amid concerns following a GPS spoofing episode at India's busiest Delhi airport last month.What is GPS spoofing?The spoofing of the Global Navigation Satellite System (GNSS) is an attempt to manipulate the navigation systems in a way that they show the wrong position, speed or time. Often confused with jamming, spoofing refers to feeding the planes false but convincing navigation data. In case of jamming however, the spectrum on which GPS satellites function is flooded.GPS spoofing attempts if successful can pose grave threats to flights by causing errors in route or altitude. However, the civil aviation minister told the House that the signals had no impact movements of flights since conventional navigational aids were operational.Naidu said that such interference reports were being received from Kolkata, Amritsar, Mumbai, Hyderabad, Bengaluru and Chennai airports. He also said that advanced cyber security solutions for IT Networks and Infrastructure were being implemented.What happened at Delhi airport?The union minister's remarks in Rajya Sabha come weeks after over 400 flights were affected and delayed at Delhi's Indira Gandhi International Airport (IGIA) after a technical snag in the air traffic control (ATC) system.The issue was later identified with the Automatic Message Switching System (AMSS), which feeds crucial flight plan data to the Auto Track System (ATS). Authorities had to process flight plans manually, which led to several delays. Referring to the incident on Monday, minister of state for civil aviation Murlidhar Mohol in a written reply said that the Airports Authority of India (AAI) has been directed to conduct a comprehensive audit to ensure such incidents do not recur.Meanwhile, the Directorate General of Civil Aviation (DGCA) had reportedly asked airlines, pilots and air traffic controllers to report GPS spoofing incidents within 10 minutes of the occurrences.