As the idiom goes that espionage is the world's second oldest profession. Unbeknown to the larger public, we do have some of the best ELINT / SIGINT gathering capabilities in the region rivalling that of China and Japan, just a little something (along with many others) that we picked up along the way from the generous assistance of the Israeli intelligence community throughout the decades since our independence.
With the majority of the
world's submarine communications cables routed through us together with numerous antenna farms including three major satellite earth stations receiving and transmitting thousands of petabits of information every single day and this kind of just enable clandestine interception to be implemented relatively easy.
IIRC, the RSAF even flew ELINT / SIGINT reconnaissance and surveillance ("Tron Sniffing") sorties with a modified variant of our Lockheed Martin C-130H Hercules fitted with classified modular payload and Fokker 50 "Enforcer Mk. II" Maritime Patrol (MPA) / Utility (UTA) aircraft much akin to the USAF Lockheed Martin EC-130H Compass Call on a regular basis throughout the region, identifying and mapping electronic signature emissions so as to better generate a better picture pertaining to an electronic order of battle (orbat)of any possible potential adversary(s).
All in all, what we are doing might just make AUSCANNZUKUS ECHELON seems like a a walk in the park.