A 10GBASE-ER SFP module is a 10Gbps Ethernet optical transceiver designed for long-distance transmission over single-mode fiber, with a maximum reach of up to 40km under the IEEE 802. In modern optical transport networks, 100G optical modules with a transmission distance of 40km have emerged as a core technology to meet the needs of carriers' backbone networks, large enterprises, and cloud service providers. Compared with short-reach and long-reach 10G SFP+ optics. igned for 40km optical communication applications. The module converts 8 channels of 50Gb/s (PAM4) electrical input data to 4 channels of LAN WDM optical signals and multiplexes them into Char nd not the principal indicator of signal strength. This makes it good for long network connections. These help keep signals strong. For distances ≥40km, 1550nm wavelength is commonly used.