  Intelligent reflecting surfaces (IRSs) have several prominent advantages,
including improving the level of wireless communication security and privacy.
In this work, we focus on the latter aspect and introduce a strategy to
counteract the presence of passive eavesdroppers overhearing transmissions from
a base station towards legitimate users that are facilitated by the presence of
IRSs. Specifically, we envision a transmission scheme that cycles across a
number of IRS-to-user assignments, and we select them in a near-optimal
fashion, thus guaranteeing both a high data rate and a good secrecy rate.
Unlike most of the existing works addressing passive eavesdropping, the
strategy we envision has low complexity and is suitable for scenarios where
nodes are equipped with a limited number of antennas. Through our performance
evaluation, we highlight the trade-off between the legitimate users' data rate
and secrecy rate, and how the system parameters affect such a trade-off.
