Cisco SFP-25GBX-U-40 Compatible SFP28 25GBASE-U BiDi 1270nm-TX/1310nm-RX 40km DOM Simplex LC/UPC SMF Optical Transceiver Module

Overview

This is the “upstream” component of a high-performance SFP28 25G BiDi 40km transceiver pair, specifically engineered as a plug-and-play alternative for the Cisco SFP-25GBX-U-40 module. It enables 25Gbps bidirectional data transmission over a single strand of single-mode fiber, making it an indispensable tool for network capacity upgrades where fiber resources are limited. This module transmits on the 1270nm wavelength and receives the 1310nm signal from its downstream partner.

Leveraging Bi-Directional (BiDi) Wavelength Division Multiplexing (WDM), this SFP28 transceiver is perfectly aligned with the demands of modern high-speed networks, particularly 5G fronthaul (eCPRI/CPRI) and data center interconnects. Consequently, it delivers a cost-effective and efficient pathway to scale network infrastructure without the need for additional fiber deployment.

Key Features

• High-Speed 25G Performance: Supports data rates up to 25.78Gbps to handle high-bandwidth traffic.
• 40km Transmission Distance: Establishes stable, long-distance links for campus, metro, and 5G applications.
• Single Fiber Connectivity: Employs WDM technology with a 1270nm-TX/1310nm-RX wavelength pair, saving on fiber cabling costs.
• Guaranteed Compatibility: Functions as a seamless, direct replacement for the SFP-25GBX-U-40.
• Built for 5G Networks: Designed to meet the stringent latency and bandwidth requirements of 5G fronthaul.
• Hot-Pluggable SFP28 Footprint: Enables installation, removal, or replacement without causing network disruption.
• Digital Optical Monitoring (DOM): Allows for real-time monitoring of key operational parameters for proactive network maintenance.

Applications

The single-fiber efficiency and high performance of this 25GBASE-BX-U SFP28 module make it a superior choice for next-generation network build-outs. It is frequently deployed in scenarios requiring a significant bandwidth upgrade over existing single-fiber runs. Key applications include:

• 5G Fronthaul and Midhaul (eCPRI/CPRI)
• Fiber-to-the-Antenna (FTTA) Infrastructure
• Data Center Interconnects (DCI)
• Enterprise and Campus Backbone Networks
• 25G Ethernet and High-Speed Storage Links

Specifications

Advantages

Choosing this single fiber 25G upstream transceiver provides a strategic advantage for network evolution and budget management. Each module undergoes exhaustive testing in target network hardware to ensure flawless performance and compatibility. This strict quality assurance guarantees seamless integration with OEM platforms and other MSA-compliant devices, offering you complete network design freedom and protecting your investment.

The robust construction of this 40km SFP28 BiDi module ensures dependable, long-term operation, which translates to higher network uptime and lower maintenance overhead. Its simple, plug-and-play installation allows network teams to deploy or upgrade high-speed links quickly and efficiently. In summary, it is the intelligent choice for maximizing the capability of your fiber infrastructure.

FAQ (Technical & Product Questions)

1. What is an ‘upstream’ BiDi transceiver?

An upstream BiDi transceiver, marked by the ‘U’ in a model name like SFP-25GBX-U-40, is one half of a matched pair. It is designed to transmit on a specific wavelength (1270nm for this module) and receive on a different wavelength (1310nm) that is being transmitted by its ‘downstream’ partner at the other end of the fiber.

2. Must I pair this SFP-25GBX-U-40 module with a specific partner?

Yes, this is mandatory for a functional link. This upstream SFP-25GBX-U-40 module must be connected to a downstream SFP-25GBX-D-40 module on the other side of the single fiber strand.

3. What is the difference between SFP-25GBX-U-40 and SFP-25GBX-D-40?

The only difference is the reversal of the transmit (TX) and receive (RX) wavelengths. The ‘U’ module transmits at 1270nm and receives at 1310nm, while the ‘D’ module does the opposite (TX 1310nm / RX 1270nm). This allows them to communicate simultaneously over a single fiber.

4. Can this 25G SFP28 module work in a 10G SFP+ slot?

Generally, yes. The SFP28 form factor is backward compatible with SFP+ ports. However, if you plug this 25G module into a 10G port, it will negotiate down and operate at a 10Gbps data rate, not its full 25Gbps capacity.

5. What does 1270nm-TX/1310nm-RX signify?

This technical specification defines the optical wavelengths for this specific module. The 1270nm-TX means it transmits a 1270 nanometer light signal, and the 1310nm-RX means it is built to receive a 1310 nanometer signal from its partner module.

6. How does this module help in 5G network deployment?

The SFP28 form factor provides a direct upgrade from 10G SFP+ with 2.5 times the bandwidth. By using a 25G BiDi SFP28, operators can upgrade their fronthaul links to support 5G capacity demands over their existing single-fiber infrastructure, saving enormous costs on new fiber installation.

7. What type of fiber patch cord should I use?

You must use a single-mode fiber (SMF) patch cord. Because this is a single fiber 25G transceiver, the cable needs to be terminated with Simplex LC connectors to match the module’s single optical port.

8. Is Digital Optical Monitoring (DOM) supported?

Yes, this module fully supports DOM (also known as DDM). This allows network administrators to access real-time diagnostic information from the transceiver, such as optical TX/RX power, temperature, and voltage, which is essential for troubleshooting and maintaining link health.