OM3, OM4, and OM5 are types of multi-mode optical fibres commonly used in data centres and enterprise environments to support various network speeds and transmission distances, including 10 gigabit Ethernet (10G), 40 gigabit Ethernet (40G), 100 gigabit Ethernet (100G) and 400. OM3, OM4, and OM5 are types of multi-mode optical fibres commonly used in data centres and enterprise environments to support various network speeds and transmission distances, including 10 gigabit Ethernet (10G), 40 gigabit Ethernet (40G), 100 gigabit Ethernet (100G) and 400. 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 propagated and limits the maximum length of a transmission link because of modal dispersion. 1 defines the most widely used. Multimode fiber is a common choice to achieve 10 Gbit/s speed over distances required by LAN enterprise and data center applications. With so. It was usually used for 100M Ethernet transmission links, but it is capable of transmitting 1G Ethernet up to 275 meters and 10G Ethernet up to 33 meters. The OM2 fiber type of multimode was standardized in 1998. The vast majority of commercial buildings and data centers fall within these ranges, and because of LOMMF's lower installation and operation costs, make. This guide explains the five generations of multimode fiber - OM1, OM2, OM3, OM4, and OM5 - covering their physical characteristics, color coding, bandwidth, maximum distances at different data rates, optical sources (LED, VCSEL, SWDM), and real-world applications in enterprise networks and data.