What is the difference between single-mode fiber jumpers and multi-mode fiber jumpers?

1、 The most fundamental difference: different core diameters
Multimode fiber (MM)
Core: 50 μ m/62.5 μ m (very thick)
Light reflects and propagates through multiple paths inside, causing it to wander aimlessly
Single mode fiber (SM)
Core: 9 μ m (very fine)
Light propagates almost in a straight line, with only one path of light
multimodal
Gigabit: several hundred meters
10G: OM3 is about 300m, OM4 is about 550m, OM5 is slightly longer
40G/100G: It can only be used for a few tens of meters, suitable for short circuiting inside cabinets and in the same computer room
single mode
Gigabit/10G: Easily travel over ten kilometers
400G/800G long-distance optical modules can reach tens of kilometers, standard for industrial parks, cross building, and operator trunk lines
4、 OM1/OM2/OM3/OM4/OM5 Multimode Level Brief Explanation
OM1 (62.5 cores): Old and low-speed, basically eliminated
OM2 (50 cores): Gigabit commonly used
OM3: 10 Gigabit Mainstream
OM4: 10 Gigabit Long Distance, 100G Short Distance Interconnection
OM5 (Broadband Multimode): Supports multiple wavelengths and is designed for 200G/400G short-range parallel interconnection
5、 How to choose the usage scenario
Choose multiple modes
Short distance wiring within the computer room and between cabinets (＜ 550 meters)
Low cost budget and a large number of high-density jumpers
Short jump connection of switches on the same floor
Choose Single Mode
Cross building, park, long-distance transmission (>1km)
Telecom PON broadband, government enterprise dedicated line, metropolitan area network
400G/800G long-distance interconnection, long-distance fiber optic transceiver
6、 Error prone reminder
Cannot be mixed: Single mode optical modules cannot be directly plugged into multi-mode jumpers, and vice versa will result in no light and packet loss;
Quick discrimination of outer skin color: yellow=single-mode, orange/blue=multi-mode;
The same interface (SC/LC/FC) can be used for both single-mode and multi-mode, depending on the internal fiber core.