When using an optical module, we must consider its wiring problem. How to choose a suitable fiber jumper according to the optical module?
1. Transmission distance and data rate
Optical modules have a variety of different transmission rates and transmission distances. When we choose optical fibers for optical modules, we must choose matching optical fiber jumpers. The multi-source agreement (MSA) specifies the working wavelength, transmission distance and data rate of various optical modules in detail. It also lists the suitable fiber types, which also has a certain reference effect on the selection of fiber jumpers. The following table is the specific details of the optical module.
| Optical module type | Operating wavelength | Fiber type | Data rate | Transmission distance |
| SR | 850nm | multimode | 10G | 300m |
| LR | 1310nm | single mode | 10G | 10Km |
| ER | 1550nm | single mode | 10G | 40Km |
| ZR | 1550nm | single mode | 40G | 80Km |
| SR4 | 850nm | multimode | 40G | 100m |
| SR10 | 850nm | multimode | 100G | 100m |
2. Interface
When choosing a fiber optic jumper, the interface is an essential consideration. Usually, the interface of the optical module usually has 2 ports (one for receiving optical signals and one for transmitting optical signals), that is, duplex SC or duplex LC, therefore, requires the use of duplex SC/LC fiber. However, the newly launched optical modules in recent years have only one port (which can receive optical signals and transmit optical signals), so simplex optical fibers need to be used. Different connectors can be inserted into different devices. If the ports at both ends of the device are the same, we can use MPO-MPO/LC-LC/SC-SC fiber optic patch cords. If you want to connect devices with different port types, you can use LC-SC/LC/ST/LC-FC hybrid fiber patch cords.
| Interface Type | Application |
| 56.4mm MPO/MTP interface | multi-fiber transceiver, 40G QSFP+/100G QSFP+ optical module |
| 2.5mm SC interface | data communication, electronic communication, GPON, EPON, X2, XENPAK optical module |
| 2.5mm ST interface | data communication, FTTH, military, campus, corporate network |
| 2.5mm FC interface | data communication, electronic communication, measurement equipment, single-mode laser |
| 1.25mm LC interface | high-density wiring, SFP SFP+ optical module, XFP optical module |
3. Optical fiber jumpers commonly used in optical modules
| Fiber jumper | Applicable optical module |
| 24-core MPO/F-MPO/, F50/125 multimode fiber optic jumper | CFP2-100G-SR10，CXP-100G-SR1 |
| 12-core MPO/F-MPO/F, 50/125 multimode 10 Gigabit fiber optic jumper | QSFP-100G-SR4，QSFP-40G-SR4，QSFP-40G-eSR4，QSFP-40G-CSR4 |
| 12-core MPO/F-MPO/F, 9/125 single-mode fiber optic jumper | QSFP-100G-PSM4，QSFP-40G-PLR4L，QSFP-40G-IR4，QSFP-40G-LR4 |
| Duplex LC-LC, 9/125 single-mode fiber optic jumper | SFP-XG-LH-SM1550，SFP-XG-LX-SM1310 QSFP-40G-BIDI-WDM1310，QSFP-40G-LR4 QSFP-40G-ER4，CFP-40G-LR4，CFP2-100G-LR4，CFP-100G-ER4，CFP-100G-LR4，QSFP-100G-LR4 |
| Duplex LC-LC, 50/125 multimode 10 Gigabit fiber optic jumper | QSFP-40G-BIDI-SR-MM850，QSFP-40G-UNIV，SFP-XG-SX-MM850，SFP-XG-LX220-MM1310 |
Summary
After reading these three factors that need to be considered before choosing, let’s give an example. The transmission rate of the optical module QSFP-100G-SR4-MM850 is 100Gbps, and it is usually used with multimode fiber (MMF). The center wavelength is 850nm. The device type is MPO, which can use 12-core MPO/F-MPO/F fiber optic jumper, the fiber diameter is 50/125um, and the transmission distance is 70m.
