Singlemode fiber (OS2) makes use of a smaller core 9µm and operates at the wavelength between 1260nm-1650nm. Singlemode transceiver technology can support fast data transmission speed (i. Example reach: a 10G SFP + at 1310 nm typically reaches ~10 km; at 1550 nm similar optics can reach 40–80 km, and specialty OS2 optics extend to ~200 km+ under ideal. At their core, 1G SFP modules are small optical or electrical transceivers that conform to 1000BASE Ethernet standards. Their function is to change electrical signals coming from switches or routers to optical signals, and vice versa, depending on whether they are being used with fiber or copper. Single-mode optical fiber transceivers are available in various wavelengths, including 850nm, 1310nm, 1550nm, and CWDM wavelengths. This allows for the flexibility to choose the optimal wavelength for the fiber optic cable and the networking equipment. These wavelengths have longer waveforms, resulting in less fiber attenuation, and they have nearly zero. 10G SFP+ optical transceivers are mainly classified by transmission technology, covering CWDM SFP+ optical transceivers, DWDM SFP+ optical transceivers, BiDi SFP+ optical transceivers and dual-fiber SFP+ optical transceivers.