OS1 single mode fiber optic cables are made with a single mode fiber core, which means that they have a very small core diameter of 9 microns. This allows the cables to transmit data over much longer distances than multimode fibers, with less signal loss and better quality. A 1-core fiber is like a single-lane road—only one car (or data signal) can travel at a time. Modes are the possible solutions of the Helmholtz equation for waves, which is obtained by combining. Single-mode fiber and multimode fiber cables are the 2 types of fibers available for use in networking infrastructure, each with their own characteristics, benefits, and scenarios they perform best in.