Fiber optic connectors are unique. Fiber cables transmit pulses of light instead of electrical signals, so the terminations must be much more precise. Instead of merely allowing pins to make metal-to-metal contact, fiber optic connectors must align microscopic glass fibers perfectly in order to allow for communication. While there are many different types of fiber connectors, they share similar design characteristics. Simplex vs. duplex: Simplex means 1 connector per end while duplex means 2 connectors per end. There are three major components of a fiber connector: the ferrule, the connector body, and the coupling mechanism.