40km optical modules support long-reach high-speed transmission over single-mode fiber, typically using 4-lane CWDM or LAN WDM optics with QSFP+ or QSFP28 interfaces.

Key Types and Standards

• 40GBASE-ER4: A 40GbE standard using four CWDM wavelengths (1271nm, 1291nm, 1311nm, 1331nm) over single-mode fiber, achieving up to 40km reach. It splits a 40Gbps signal into four ~10Gbps lanes, multiplexed onto a duplex LC fiber pair, and demultiplexed at the receiver. Compliant with IEEE 802.3ba and QSFP+ MSA, it is widely used in metro and extended campus networks .
• 100GBASE-ER4 / ER4L QSFP28: Converts four 25Gbps electrical channels into four LAN WDM optical signals, multiplexed into a single fiber for 100Gbps transmission. Typical wavelengths are 1296nm, 1300nm, 1305nm, and 1309nm. FEC support extends reach to 40km, while APD receivers ensure high sensitivity .
• 100G OWDM: Supports 8 channels with 400GHz spacing in the O-band, reaching 40km without amplifiers or dispersion compensation. It features low power consumption (~5.5W) and Digital Optical Monitoring (DOM) for operational efficiency .

Optical and Electrical Parameters

• Transmission Distance: Up to 40km over single-mode fiber.
• Wavelengths: CWDM or LAN WDM channels, e.g., 1271–1331nm for 40GBASE-ER4, 1296–1309nm for 100G ER4.
• Data Rate: 40Gbps for ER4, 100Gbps for ER4/ER4L modules.
• Lanes: 4 optical lanes per module; 40G splits 40Gbps into 4×10Gbps, 100G splits 100Gbps into 4×25Gbps.
• Connectors: Duplex LC/UPC for single-mode fiber.
• Receiver Type: APD (Avalanche Photodiode) for high sensitivity.
• Power Consumption: Typically 5–6W for 100G modules.
• FEC Support: Forward Error Correction enabled to achieve full 40km reach.

Applications

• Data Center Interconnects (DCI)
• Metro and backbone networks
• Extended campus networks
• Scenarios where 10km or 20km optics are insufficient but DWDM is unnecessary

Additional Features

• Digital Optical Monitoring (DOM): Provides real-time monitoring of optical power, temperature, and voltage.
• Multiplexing: CWDM or LAN WDM MUX/DEMUX integrated for single-fiber transmission.
• Compatibility: QSFP+ or QSFP28 form factors, compliant with IEEE and MSA standards. These parameters ensure high-speed, long-reach, and reliable optical transmission for modern network deployments, balancing performance, cost, and operational efficiency .