  Automatic Dependent Surveillance Broadcast (ADS-B) sensors deployed on the
ground are central to observing aerial movements of aircraft. Their
unsystematic placement, however, results in over-densification of sensor
coverage in some areas and insufficient sensor coverage in other areas. ADS-B
sensor coverage has so far been recognized and analyzed as an availability
problem; it was tackled by sensor placement optimization techniques that aim
for covering large enough areas. In this paper, we demonstrate that the
unsystematic placement of ADS-B sensors leads to a security problem, since the
realization and possible deployment of protective mechanisms is closely linked
to aspects of redundancy in ADS-B sensor coverage. In particular, we model
ADS-B sensor coverage as a multi-dimensional security problem. We then use
multi-objective optimization techniques to tackle this problem and derive
security-optimized near-optimal placement solutions. Our results show how the
location of sensors play a significant role in reducing the success rate of
attackers by providing a sufficient number of sensors within a specific
geographical area to verify location claims and reducing the exposure to
jamming attacks.
