Abstract: A multi-stage switching network in which a plurality of optical binary couplers are symmetrically connected to each other relative to the center line of the switching network and pyramids of the optical binary couplers individually associated to switching network terminals are provided, and every optical binary coupler in said pyramids is unconnected at one of its two light-conducting paths on that side which faces away from the center line of the switching network, and across the center line of the switching network, every binary coupler pyramid is connected in a light-conducting manner to every binary coupler pyramid lying at the other side such that every switching network through-connect path outgoing from a switching network terminal or, respectively, leading to a switching network terminal contains an unconnected light-conducting path of an optical binary coupler when all binary couplers are in the crossed through-connect condition.