OM3 and OM4 fibers are compatible with each other in the sense that they can be connected and used within the same network. OM4 is another multimode fiber option, and in most cases, it also uses an aqua jacket (some companies use a purple jacket to distinguish it from OM3). However, despite their similar core size and compatibility, these two fiber standards differ in modal bandwidth, maximum. These differences include the maximum distance and speed, the standard release date, the modal bandwidth, the size of the fiber core, the color of the fiber jacket, and the typical applications from a data rate perspective. While they share similarities, they also have distinct differences that can impact their use in a network. There also are four types of multimode fiber identified by the “OM” (optical multi-mode) designation described by the ISO/IEC 11801 and they are: OM1, OM2, OM3 and OM4.
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