Optical apparatuses providing optical interconnections among a plurality N of electronic components. One exemplary apparatus comprises a slab waveguide having a core layer that enables light beams to propagate in a plurality of directions, a plurality of N reception ports, and a plurality of N transmission ports, each reception port and each transmission port serving a respective electronic component, and each being optically coupled to the core layer of the slab waveguide. Each transmission port is configured to receive a plurality of light beams from its assigned electronic component and to transmit each received light beam onto the slab waveguide in a direction toward a reception port. Each reception port is configured to receive from the slab waveguide a plurality of light beams transmitted to it from at least two different transmission ports. Light beams within the slab waveguide are permitted to cross paths. Other exemplary embodiments are disclosed.