Simplex Patch Cord: Contains one fiber, used for one-way data transmission. Optical fiber cable, or optical cord, is a basic and necessary component in fiber optic network. Different kinds of fiber optic patch. Duplex fibre optic cable is a high-speed networking solution consisting of two independent strands of glass or plastic fibre. Typically constructed in a “zipcord” (side-by-side) layout, it enables full-duplex communication, allowing data to be transmitted (TX) and received (RX) simultaneously. What is a duplex fiber optic patch cord? Duplex is divided into half duplex and full duplex. LSZH (Low Smoke Zero Halogen):. Duplex Fiber Optic Cable can be half-duplex or full-duplex, but the transmission method of both is the same.