The feasibility of a passive fiber optic bus that uses bidirectional integrated optics bus access couplers is studied. The number of bus nodes can be increased when an optimized asymmetric bus access coupler is used instead of a symmetric one. A modified Ag-Na ion exchange process provides the possibility of manufacturing integrated optics asymmetric couplers for the bus. The process is suitable for the processing of integrated optics components that combine deep multimode waveguides with different core sizes on a single substrate. An access coupler is designed, modeled, and processed. The coupler is optimized for seven nodes; the asymmetry of the coupler is 5 dB.