Figure 1 gives an overview of the secure system architecture proposed for the FAST project. The system comprises an aircraft on-board segment, a satellite segment, and a ground segment. The ground system is formed by a satellite gateway (GW) connected to an ATN router for aeronautical services, and an Internet router for passengers services. Onboard, a satellite terminal is connected to an ATN router for the ATS traffic and a New Generation (NG) router connected to the APC, AOC, medical supervision and video surveillance systems (noted AOC NG – Next Generation).