Almost all multimode fiber sizes are 50/125um or 62.5/125um, and bandwidth (the amount of information transmitted by the fiber) is typically 200MHz to 2GHz. Multimode optical terminals can be transmitted up to 5 km through multimode fiber. Light emitting diodes or lasers.
Pull ring or in vitro color is black.
The size of single-mode fiber is 9-10/125µm, and it has the characteristics of unlimited bandwidth and lower loss compared to multimode fiber. and cascaded terminals are mostly used for long-distance transmission, sometimes up to 150 to 200 kilometers. The LED is used as the light source with a narrower of LD or spectral line. Pull ring or in vitro color is blue, yellow or purple.