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. 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. Multimode Fiber (MMF) has a core diameter, typically 50–100 micrometers, has ability to transfer multiple modes of light through the fiber core, uses lower-cost electronics (LED, VCSEL) operates at the 850 nm and 1300 nm wavelength and is used for short distance interconnections (up to 550m). Multimode fiber is a common choice to achieve 10 Gbit/s speed over distances required by LAN enterprise and data center applications. There are several kinds of multimode fiber types available for high-speed network installations, and each with a different reach and data-rate capability. This larger core allows easier light injection and lower-cost optical sources (LEDs and VCSELs), making multimode fiber the cost-effective choice for. Multimode fiber (MMF) continues to play a critical role in today's high-bandwidth, short-range optical networks. Its common core-cladding sizes are 62. 5/125µm and 50/125µm, which are much larger than the 9/125µm core of. “OM” stands for Optical Multimode, which is a classification system for multimode fiber. This allows multiple light paths to travel at the same time.