Multimode fiber cable is prefixed with 'OM' and Single mode fiber cable is prefixed with 'OS'. Although they can do the same job in some instances, the different construction methods make each of them better suited to certain tasks and budgets. That makes picking between single mode and multimode fiber optic cables an. Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Multi-mode links can be used for data rates up to 800 Gbit/s. Multi-mode fiber has a fairly large core diameter that enables multiple light modes to be. Multimode fiber is a type of optical fiber that carries multiple light signals simultaneously through a larger core - typically 50 or 62.