HP 6125XLG HP Comware-Based Switches Transceiver Modules User Guide - Page 8

Fiber Fiber mode Depending on the mode of light transmission in fibers, fibers fall into single-mode and multimode.  Multimode fibers Multimode fibers (MMFs) have thicker fiber cores and can transport light in multiple modes. However, the intermodal dispersion is greater and worsens as the transmission distance increases. Multimode fibers can be classified into multiple grades according to their diameters and modal bandwidth. For more information, see Table 2. The modal bandwidth of a multimode fiber is determined by the expression the modulation frequency of the maximum modulation frequency pulse that can pass a fiber × the fiber length. The modal bandwidth is a comprehensive index reflecting the optical characteristics of a multimode fiber. Table 2 Multimode fiber grades Fiber mode Multimode fiber Fiber grade FDDI-grade OM1 OM2 OM3 Fiber diameter (μm) 62.5/125 62.5/125 50/125 50/125 Modal bandwidth at 850 nm (MHz*km) 160 200 500 1500 Other factors that influence the transmission distance of multimode fibers include interface type, central wavelength, and fiber grade. For more information, see Table 3. Table 3 Multimode fiber specifications Interface type 1000BASE-SX 1000BASE-LX 10GBASE-SR Central wavelength 850 nm 1300 nm 850 nm Fiber grade FDDI-grade OM1 OM2 OM3 FDDI-grade OM1 OM2 OM3 FDDI-grade OM1 OM2 OM3 Transmission distance < 220 m (721.78 ft) < 275 m (902.23 ft) < 550 m (1804.46 ft) N/A < 550 m (1804.46 ft) < 550 m (1804.46 ft) < 550 m (1804.46 ft) N/A < 26 m (85.30 ft) < 33 m (108.27 ft) < 82 m (269.03 ft) < 300 m (984.25 ft) 4