10G SFP+ optical transceivers are mainly divided into four types: 10G SFP+ SR, 10G SFP+ LR, 10G SFP+ ER and 10G SFP+ ZR optical transceivers. Their transmission rates are all 10G, but the transmission distance and wavelength are different.
10G SFP+ SR refers to 10G multimode module with LC interface, used with multimode fibers. The wavelength is 850nm and the maximum transmission distance is 300M. So it is suitable for short-distance 10G network transmission.
The LR refers to Long Range. It's LC interface and used with single-mode fiber. The working wavelength is 1310nm and the longest transmission distance is up to10KM, which has the advantages of miniaturization, low power consumption, and long transmission distance.
ER refers to extended range. The interface type is LC, working wavelengths are 1310nm and 1550nm and longest transmission distance with single-mode fiber is 40KM. The commonly used wavelength is 1550nm, using 1310nm transmission can also reach 40KM, but its transmission mode is not stable, there will be packet loss. 10G SFP+ ER is a cost-effective ultra-long-distance optical ransceivert, which is currently popular in data centers and enterprise parks.
ZR refers to the longest distance (Ze best Range). It's LC interface, the working wavelength is 1550nm, and transmission distance with single-mode fiber can reach more than 100KM, which is suitable for long-distance transmission city domain network.