  The confining mechanisms of 't Hooft and Mandelstam have a simple microscopic
realization in 3D Z2 gauge theory: the center vortex and the magnetic monopole
condensation are associated, in the set of configurations contributing to the
confining phase, to the presence of two kinds of infinite clusters. These
generate the area law of the large Wilson loops and the universal finite size
effects produced by the quantum fluctuations of the bosonic string describing
the infrared behavior of the flux tube.
