1. QSFP28 SR4 optical module
The QSFP28 SR4 optical module is also known as the 100GBASE-SR4 QSFP28 optical module. Since most of the data centers use multi-mode optical fibers, IEEE has developed a standard for 100G QSFP28 optical modules that specifically supports multi-mode optical short-distance transmission applications: 100GBASE-SR4. QSFP28 SR4 optical module adopts 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, which is suitable for short-distance transmission. QSFP28 SR4 optical module belongs to Parallel 100G optical module has the advantages of high port density and low cost.
2. QSFP28 LR4 optical module
QSFP28 LR4 optical module is also known as 100GBASE-LR4 QSFP28 optical module. For 100G long-distance transmission, IEEE has developed the 100GBASE-LR4 standard for 100G QSFP28 optical module. The QSFP28 LR4 optical module also uses 4 optical fiber channels. The difference is that it introduces WDM technology, which can multiplex the different wavelengths of the 4 optical fiber channels onto one optical fiber for transmission. Therefore, the QSFP28 LR4 optical module uses duplex LC interface, when used with single-mode fiber, the transmission distance can reach 10km, which provides a solution for the continuous increase of transmission distance requirements of ultra-large data centers.
3. QSFP28 PSM4 optical module
QSFP28 PSM4 optical module, also known as 100GBASE-PSM4 QSFP28 optical module, has a hot-swappable QSFP shape, built-in digital diagnostic function, and has the advantages of high speed and low power consumption. 100GBASE-PSM4 is a multi-source agreement (MSA), mainly formulated for 100G QSFP28 optical modules. QSFP28 PSM4 optical module is mainly used for medium and long-distance transmission applications. It adopts MTP interface. When used with single-mode multi-core fiber, the transmission distance can reach 500m. It has eight optical fibers, and the data rate of each optical fiber is 25Gbps.
4. QSFP28 CWDM4 optical module
QSFP28 CWDM4 optical module is also known as 100GBASE-CWDM4 QSFP28 optical module, mainly used in computing, high-frequency trading and other fields, 100GBASE-CWDM4 is also a multi-source agreement (MSA), QSFP28 CWDM4 optical module also introduces WDM technology, using LC duplex interface, when used with single-mode fiber, the transmission distance can reach 2km.
