Can single-mode fiber optic cables operate in full-duplex mode

Yes, single-mode fiber can support full-duplex communication. Full-duplex communication means data can be transmitted and received simultaneously in both directions over a single fiber optic cable. To understand why this is the case, it is important to consider the concepts of half duplex and full duplex. Duplex cable consists of two fibers, usually in a zipcord (side-by-side) style. Workstations, fiber switches and servers, fiber modems, and similar hardware require duplex. There are many kinds of optical cables, such as single mode fiber optic cable, multimode fiber optic cable, simplex fiber optic cable, duplex fiber optic cable. [pdf]