In November 2014, the first ever use of gigabit laser-based communication as part of the European Data Relay System (EDRS) was carried out.[21] Further system and operational service demonstrations were carried out in 2014. Data from the EU Sentinel-1A satellite in LEO was transmitted via an optical link to the ESA-Inmarsat Alphasat in GEO and then relayed to a ground station using a conventional Ka-band downlink.