Fiber optic cables are essential components in modern data transmission infrastructure. They support high-speed, interference-resistant communication and are particularly effective in applications that require high bandwidth, low latency, and strong signal integrity. This document discusses different types of communication channels and their characteristics. Introduction One of the important properties of optical fiber is signal attenuation. transmission medium is a path between the. The EN 50173-1 standard describes different categories of fibre-optical cables (OM1, OM2, OM3, OM4, OS1, OS2) and different classes of FO channels (OF100, OF-300, OF-500, OF-2000, OF-5000, OF-10000).