The first is to introduce the difference between multimode fiber and single mode fiber:

Multimode fiber
The optical signal in multimode fiber propagates through multiple channels; it is usually recommended to be used when the distance is less than miles.
The effective distance of multimode fiber from transmitter to receiver is about 5 miles. The usable follow-up is also affected by the type and quality of the transmitting/receiving device; the stronger the light source, the more sensitive the receiver, and the longer the distance. Research shows that the bandwidth of multimode fiber is about 4000Mb/s.
The single-mode fiber is manufactured to eliminate pulse broadening. Due to the small size of the core (7-9 microns), light jumps are eliminated. A focused laser source is used at 1310 and 1550nm wavelengths. These lasers irradiate directly into the tiny fiber core and propagate to the receiver with no obvious jump. If multi-mode can be compared to hunting, and many projectiles can be loaded into the barrel at the same time, then single-mode is ***, and a single light is like a bullet.

Single mode fiber
The core of a single-mode fiber is thin, allowing light to be emitted directly to the center. It is recommended to use when the distance is long.
In addition, the distance loss of single-mode signals is smaller than that of multi-mode signals. At the distance of the first 3000 feet, multimode fiber may lose 50% of its LED light signal strength, while single-mode only loses 6.25% of its laser signal at the same distance.
The single-mode bandwidth potential makes it the only choice for high-speed and long-distance data transmission. Recent tests have shown that 64 channels of 40G Ethernet can be transmitted over a distance of 2,840 miles on a single-mode optical cable.
In safety applications, the most common determinant of multimode or single mode is distance. If there are only a few miles, multimode is preferred because the LED transmitter/receiver is much cheaper than the laser required for single mode. If the distance is greater than 5 miles, single-mode fiber is best. Another issue to consider is bandwidth; if future applications may include the transmission of large-bandwidth data signals, then single-mode will be the best choice.

Based on the above analysis, we believe that users should invest in the best performance at the lowest price from the perspective of application, transmission distance, forward-looking perspective, and cost perspective.