Security has become a critical concern for avionic actors due to the increasing threats targeting embedded systems
and also to the recent evolutions of avionic systems. The threat surface of an aircraft has always been very light because of
strong safety requirements. Therefore the aircraft transportation domain remains up to now, one of the most safe.

Additional technical and organizational security measures begin to be deployed on recent airplanes to enhance protec-
tion against potential malicious threats. Nevertheless, continuous evolution of cyber threats imposes to reconsider the security
of systems or the future. Several studies propose to introduce Intrusion Detection Systems (IDS) in embedded systems. This
paper briefly describes the challenges raised by the introduction of such techniques in avionics systems and proposes a Host-based IDS process that is designed to fit avionics systems constraints.