1. Different transmission methods
100G QSFP28 SR4 optical module and 100G QSFP28 PSM4 optical module both adopt 12-channel MTP interface, and realize 8-channel optical fiber bidirectional 100G transmission at the same time.
100G QSFP28 LR4 optical module and 100G QSFP28 CWDM4 optical module use 4 independent wavelength channels for 100G transmission, and use wavelength division multiplexing technology to multiplex the four wavelength signals onto a single-mode optical fiber for transmission.
2. Transmission medium and transmission distance are different
The transmission distance of 100G QSFP28 SR4 optical module, 100G QSFP28 LR4 optical module, 100G QSFP28 PSM4 optical module and 100G QSFP28 CWDM4 optical module are different.
100G QSFP28 SR4 optical module is usually used together with MTP multi-mode fiber. When used with OM3 fiber, the transmission distance can reach 70m, and when used with OM4 fiber, the transmission distance can reach 100m.
100G QSFP28 LR4 optical module is usually used together with LC duplex single-mode fiber, and the transmission distance can reach 10km.
100G QSFP28 PSM4 optical module is usually used together with MTP single-mode fiber, and the transmission distance can reach 500m.
100G QSFP28 CWDM4 optical module is usually used together with LC duplex single-mode fiber, and the transmission distance can reach 2km.
3. Different wiring structure
The wiring structure of the 100G QSFP28 SR4 optical module and the 100G QSFP28 PSM4 optical module are the same, and both require a multi-fiber wiring structure based on the 12-way MMF MTP interface. The difference is that the 100G QSFP28 PSM4 optical module must operate in a single-mode fiber The 100G QSFP28 SR4 optical module is in the multi-mode fiber.
And 100G QSFP28 LR4 optical modules and 100G QSFP28 CWDM4 optical modules are usually used together with LC duplex single-mode fiber patch cords, using dual-pass dual-fiber SMF wiring structure.
4. Working principle is different
The working principle of the 100G QSFP28 SR4 optical module and the 100G QSFP28 PSM4 optical module are basically the same. When transmitting signals at the transmitting end, the electrical signals are converted into optical signals by the laser array, and then transmitted in parallel on the optical fiber. When reaching the receiving end, The photodetector array converts parallel optical signals into parallel electrical signals, except that the former is on a multi-mode fiber and the latter is on a single-mode fiber.
The working principle of the 100G QSFP28 LR4 optical module and the 100G QSFP28 CWDM4 optical module are the same. They both convert 4 25Gbps electrical signals into 4 LAN WDM optical signals, and then multiplex them into a single channel to achieve 100G optical transmission. At the receiving end, the module demultiplexes 100G optical input into 4 LAN WDM optical signals, and then converts them into 4 electrical signal output channels.
Application selection of 100G QSFP28 optical module
Under the 100G network, how to choose a suitable 100G QSFP28 optical module can be considered from the following three aspects:
1. Multimode fiber optic cabling between switches: 5-100m
Optional 100G QSFP28 SR4 optical module, which uses MTP interface (8 cores), the transmission distance when used with OM3 multimode fiber is 70m, and when used with OM4 multimode fiber, the transmission distance is 100m, suitable for short-distance transmission (The distance is less than 100 meters) in the 100G network.
2. Single-mode fiber wiring between switches: >100m-2km
You can choose 100G QSFP28 PSM4 optical module or 100G QSFP28 CWDM4 optical module, both of which are suitable for medium and short distance 100G networks. The 100G QSFP28 PSM4 optical module uses 8 parallel single-mode optical fibers together, and the transmission distance is about 500 meters; the 100G QSFP28 CWDM4 optical module is used together with the single-mode optical fiber, and the transmission distance can reach 2 km.
3. Long-mode single-mode fiber: ≤10km
can choose 100G QSFP28 LR4 optical module, it adopts duplex LC interface, transmission distance can reach 10km when used with single-mode fiber, suitable for long-distance 100G network (distance more than 2 kilometers and less than 10 kilometers).
HUANET can provide all these 100G QSFP28 optical modules with competitive price, welcome to send us inquiry.
Post time: Jun-17-2021