1.25G BiDi SFP Module, Gigabit LC SMF 20km DDM Transceiver Pair

Product Overview

The Luleey 1.25G BiDi SFP Module is designed for Gigabit Ethernet transmission over single mode single fiber. It uses BiDi wavelength division technology to transmit and receive optical signals through one LC simplex fiber connection, helping network engineers reduce fiber core usage while maintaining stable 1.25Gbps optical performance.

Unlike standard dual-fiber SFP modules that require two fiber cores, this Gigabit SFP LC Module uses a 1310nm/1550nm wavelength pair over one single mode fiber. It is supplied as a matched pair, making it suitable for point-to-point Gigabit fiber links where fiber resources are limited.

This 1.25G SFP Transceiver supports DDM monitoring for optical diagnostics and is suitable for switches, routers, media converters, network firewalls, fiber optic network cards, servers, storage systems, security networks, campus networks, telecom rooms, and building-to-building Ethernet links.

Luleey provides compatibility options for major switch and router platforms, helping users deploy stable 1G fiber links across different network environments.

Features

• 1.25G BiDi SFP Module for Gigabit single-fiber transmission
• Supplied as a matched transceiver pair
• LC simplex interface for single fiber deployment
• 1310nm / 1550nm wavelength pair
• Supports up to 20km transmission over single mode fiber
• DDM digital diagnostic monitoring support
• 1.25Gbps optical transmission speed
• 3.3V SFP operating voltage
• Zinc-magnesium alloy housing for stable operation
• Suitable for Gigabit switches, routers, firewalls, servers, and media converters
• Compatible coding options for Cisco, Huawei, MikroTik, Ubiquiti, ZTE, HPE-Aruba, Juniper, Intel, TP-Link, H3C, and more
• Helps save fiber cores compared with dual-fiber SFP modules
• Factory tested by Luleey for stable optical performance

Applications

• Gigabit Ethernet Fiber Links
• Single Fiber Network Deployment
• Switch-to-Switch Gigabit Uplink
• Router-to-Switch Fiber Connection
• Fiber Media Converter Deployment
• Security and IP Camera Networks
• Campus Fiber Networks
• Building-to-Building Ethernet Links
• Telecom Room Fiber Access
• Network Firewall Fiber Connection
• Server and Storage Fiber Connection
• Fiber Optic Network Card Connection

Specifications

Why Choose a 1.25G BiDi SFP Module?

A 1.25G BiDi SFP Module is useful when a network needs Gigabit fiber transmission but only one fiber core is available. Instead of using two separate fibers for transmit and receive, BiDi SFP modules use two different wavelengths over the same fiber.

This helps users:

• Save fiber core resources
• Upgrade existing single-fiber links
• Reduce cabling cost
• Simplify fiber deployment
• Extend Gigabit Ethernet over long distances
• Build stable point-to-point fiber connections

For building-to-building links, campus networks, security systems, and telecom room cabling, the Luleey Single Fiber SFP Module provides a practical and cost-effective Gigabit optical solution.

How BiDi SFP Transmission Works

BiDi means bidirectional transmission. A BiDi SFP module transmits and receives optical signals over one fiber core by using two different wavelengths.

A typical 1.25G BiDi pair works like this:

| Side | Transmit Wavelength | Receive Wavelength |
|—|—|
| Side A | 1310nm | 1550nm |
| Side B | 1550nm | 1310nm |

Because of this wavelength pairing, BiDi SFP modules must be used in matched pairs. Two modules with the same wavelength direction will not create a normal link.

1.25G BiDi SFP vs Standard Dual-Fiber SFP

| Module Type | Fiber Usage | Best For |
|—|—|
| Standard Dual-Fiber SFP | Uses two fiber cores | Normal Gigabit fiber links with enough fiber resources |
| 1.25G BiDi SFP Module | Uses one fiber core | Single fiber links and fiber-saving deployments |

Choose a BiDi SFP module when only one fiber core is available or when you want to reduce fiber usage.

Choose a standard dual-fiber SFP module when your fiber infrastructure already provides two available fiber cores.

Compatibility Notes

Luleey can provide compatible coding for different switch, router, firewall, and media converter platforms. Before ordering, please confirm the device brand and model to ensure correct recognition and stable operation.

Common compatibility options include:

• Cisco
• Huawei
• MikroTik
• Ubiquiti
• ZTE
• HPE-Aruba
• Juniper
• Intel
• H3C
• TP-Link
• Arista
• Brocade
• Extreme
• Mellanox
• General coding

Important Pairing Notes

This 1.25G SFP Transceiver should be used with the correct opposite wavelength module. A 1310nm TX / 1550nm RX module should be paired with a 1550nm TX / 1310nm RX module.

Before deployment, confirm:

• The fiber type is single mode
• The connector type is LC
• The link distance is within the selected optical budget
• The two modules are matched A/B wavelength pairs
• The host device supports 1G SFP modules
• The compatibility coding matches the switch or router brand
• DDM monitoring is required or supported by the host device

FAQ

What is a 1.25G BiDi SFP Module?

A 1.25G BiDi SFP Module is a Gigabit optical transceiver that transmits and receives data over one single mode fiber core using two different wavelengths.

What is this Gigabit SFP LC Module used for?

It is used for Gigabit Ethernet fiber links, switches, routers, media converters, network firewalls, servers, storage systems, and building-to-building fiber connections.

Does this module use one fiber or two fibers?

It uses one single mode fiber core through an LC simplex connector.

Does this product come as a pair?

Yes. This product is supplied as a matched BiDi transceiver pair.

What wavelengths does this module use?

It uses a 1310nm / 1550nm wavelength pair. The opposite side must use the reversed wavelength direction.

What is the transmission distance?

The main distance option is up to 20km, with selected variants also available for shorter links such as 10km.

Does it support DDM?

Yes. DDM allows monitoring of optical power, temperature, voltage, and laser status when supported by the host device.

Is it compatible with Cisco, Huawei, MikroTik or Ubiquiti?

Luleey can provide compatible coding for Cisco, Huawei, MikroTik, Ubiquiti, ZTE, HPE-Aruba, Juniper, Intel, TP-Link, H3C, and other platforms.

Can I use it with multimode fiber?

No. This module is designed for single mode fiber.

Can I use two same-side BiDi modules together?

No. BiDi modules need matched A/B wavelength pairs. Two modules with the same TX/RX direction will not work correctly.

Why choose Luleey 1.25G BiDi SFP modules?

Luleey 1.25G BiDi SFP modules provide single-fiber Gigabit transmission, DDM monitoring, compatible coding options, and factory-tested optical performance for stable enterprise, campus, security, telecom, and media converter deployment.