  We investigate the secure degrees of freedom (SDoF) of the K-user MIMO
multiple access (MAC) and the two user MIMO interference channel. An unknown
number of eavesdroppers are trying to decode the messages sent by the
transmitters. Each eavesdropper is equipped with a number of antennas less than
or equal to a known value NE. The legitimate transmitters and receivers are
assumed to have global channel knowledge. We present the sum SDoF of the two
user MIMO interference channel. We derive an upperbound on the sum SDoF of the
K-user MAC channel and present an achievable scheme that partially meets the
derived upperbound.
