Cudy Single Mode 1.25G LC Bi-Directional SFP 20km Transceiver Module

Network expansion over long distances can be costly and complex, but the Cudy SM100GSB-20AB Bi-Directional SFP transceiver streamlines the process by combining transmit and receive signals over a single strand of single-mode fiber. This compact module delivers 1.25 Gbps throughput across distances up to 20 km, making it an efficient solution for linking buildings, campuses, or remote equipment without the expense of additional fiber runs.

Who is it for

IT administrators, network engineers, and system integrators who need reliable, long-range Gigabit Ethernet connectivity in enterprise, campus, or metropolitan area networks. It is also ideal for service providers extending fiber to the premises or connecting remote switches and routers.

Main features

• Bi-Directional (BiDi) technology: transmits at 1310 nm and receives at 1550 nm over a single LC simplex fiber, halving fiber infrastructure costs.
• 20 km reach on standard single-mode fiber (SMF) with a DFB laser and PIN receiver for stable, low-power performance.
• Hot-pluggable SFP form factor compliant with MSA and IEEE 802.3z, ensuring compatibility with a wide range of networking equipment.
• Digital Diagnostic Monitoring (DDM/DOM) provides real-time monitoring of temperature, voltage, laser bias, and optical power.
• Low power consumption (<1 W) and wide operating temperature range (0°C to 70°C) for dependable operation in diverse environments.

Specifications

• Data rate: 1.25 Gbps (1000BASE-BX)
• Connector: LC simplex
• Fiber type: Single-mode (SMF)
• Wavelength: TX 1310 nm, RX 1550 nm
• Max distance: 20 km
• Laser: DFB
• Receiver: PIN
• DDM/DOM: Yes
• Hot-pluggable: Yes
• Supply voltage: 3.3 V
• Power consumption: <1 W
• Operating temperature: 0°C to 70°C
• Storage temperature: -40°C to 85°C
• Certifications: SFP MSA, IEEE 802.3z, RoHS, CE, FCC

Tips

For optimal performance, pair this BiDi transceiver with a matching opposite-wavelength module (e.g., TX 1550 nm / RX 1310 nm) on the remote end. Always clean fiber connectors before installation and use single-mode fiber with a core diameter of 9/125 µm. Verify compatibility with your switch or router vendor; this module is widely compatible with Cisco, Ubiquiti, MikroTik, TP-Link, Netgear, D-Link, Huawei, and many others.