Eavesdrop prevention
Configuring port security on a given switch port automatically enables Eavesdrop Prevention for that port. This prevents use of the port to flood unicast packets addressed to MAC addresses unknown to the switch and blocks unauthorized users from eavesdropping on traffic intended for addresses that have aged-out of the switch address table. (Eavesdrop Prevention does not affect multicast and broadcast traffic; the switch floods these two traffic types out a given port regardless of whether port security is enabled on that port.)