Multimode fiber cables in this category use graded-index glass cores — OM1 (62.5 µm), OM2 (50 µm), OM3 (50 µm laser-optimized), OM4 (50 µm high-bandwidth), and OM5 (50 µm wideband) — terminated in LC, SC, MPO/MTP, and ST connectors across simplex, duplex, and ribbon configurations. Lengths range from 0.5 m patch cords to 100 m pre-terminated trunk assemblies. Key buying considerations include bandwidth-distance rating (OM3 supports 10 GbE to 300 m; OM4 extends 10 GbE to 550 m and 100 GbE to 150 m; OM5 adds SWDM4 support for 100/400 GbE over two fibers), jacket type (OFNR riser vs. OFNP plenum for airspace routing), and polarity method (Method A/B/C for MPO trunks).

These cables connect switches, routers, storage arrays, and GPU servers within a single building or campus — anywhere runs stay under roughly 550 m and short-reach transceivers (SFP+, QSFP28, QSFP-DD) are in use. Data center operators building 10/25/40/100/400 GbE spine-leaf fabrics, HPC or AI clusters requiring dense MPO breakout cabling, and enterprise LAN teams upgrading from copper to fiber all draw from this category. OM4 and OM5 are the practical choices for new installations; OM1/OM2 appear mainly in legacy-replacement or low-speed segments.