The Singapore Satellite Positioning Reference Network (SiReNT) is a national reference network infrastructure, developed to support real-time high precision Positioning, Navigation and Tracking (PNT). An initiative by Singapore Land Authority (SLA), SiReNT supports GNSS (Global Navigation Satellite System) systems such as NAVSTAR GPS, GLONASS, QZSS, Beidou and Galileo. It provides Differential GNSS (DGNSS, also known as DGPS) services which improve the accuracy and reliability of PNT.