Issue about information provided by Optical Module

Generally, the label of an optical module provides the following information: manufacturer, serial number, speed, center wavelength, mode (single-mode/multimode), and transmission distance.
1) There are FE, GE, 10GE, 25GE, 40GE, and 100GE optical modules to suit various interface speeds, as well as those with special speeds, including 2G, 4G, 8G, and 16G optical modules.
2) Center wavelengths of optical modules include:
a) 850 nm: multimode optical modules. They are often used for short-distance transmission.
b) 1310 nm: mostly single-mode optical modules and a few multimode optical modules. They are often used for medium- or long-distance transmission.
c) 1550 nm: single-mode optical modules. They are often used for long-distance transmission.
3) Depending on core diameters and features, optical fibers are classified into single-mode and multimode fibers. Generally, multimode fibers have large core diameters and severe dispersion, so they transmit optical signals over short distances. Single-mode fibers have small dispersion and can transmit optical signals over long distances.
4) Optical signals of different wavelengths can travel different distances. Transmission distances of optical modules are affected by attenuation and dispersion of optical signals during transmission. Generally, a distance of less than 2 km is considered a short transmission distance, a distance of 10 km to 20 km is considered a medium transmission distance, and a distance beyond 20 km is considered a long transmission distance. The optical modules used on CE series switches support a transmission distance of up to 100 km.