Q: What is the difference between OM2, OM3 and OM4?
A: The terms OM2, OM3 and OM4 refer to different performance levels of multimode optical fibers. OM2 is the lowest performing of the three, while OM4 is the highest. For example, OM2 can support 10 Gigabit Ethernet up to 150 meters while OM4 can support it up to 550 meters. OM3 supports it to 300 meters. All three types of optical fibers are almost identical physically. They all have 50 micron cores and an outside diameter of 250 micron. The main difference between the three is how well the glass accommodate the light traveling down it.