SFP-8G31-EW 8G SFP+ EW 1310nm 40km LC SMF DDM Transceiver Module

Overview

The SFP-8G31-EW is a specialized, high-performance SFP+ optical transceiver module designed for long-reach 8G Fibre Channel (8GFC) applications. As an “EW” (Extended Wavelength) module, it is engineered to transmit data reliably over an extended distance of up to 40km using a high-power 1310nm DFB laser over standard single-mode fiber (SMF). This makes it an ideal solution for connecting geographically dispersed Storage Area Networks (SANs), data centers, and campus networks. This transceiver provides multi-rate functionality, ensuring backward compatibility with 4G and 2G Fibre Channel speeds, offering a flexible and robust solution for upgrading or extending existing storage infrastructure.

Key Features

• Extended Reach: Capable of transmitting data up to a maximum distance of 40 kilometers, ideal for long-haul SAN connectivity.
• Multi-Rate Capability: Supports auto-negotiation for 8G/4G/2G Fibre Channel data rates, ensuring seamless integration with legacy hardware.
• High-Performance Optics: Utilizes a reliable 1310nm Distributed Feedback (DFB) laser transmitter for stable performance over extended distances.
• Hot-Pluggable SFP+ Footprint: Adheres to the SFP+ MSA standard, allowing for installation or replacement without interrupting system operation.
• Digital Diagnostics Monitoring (DDM): Provides real-time monitoring of essential parameters such as optical power, temperature, and voltage for proactive network management.
• Low Power Consumption: Optimized for energy efficiency to help reduce overall operational costs in data center environments.
• Industry-Standard Connector: Features a duplex LC connector for compatibility with standard SMF cabling infrastructure.

Applications

With its impressive 40km reach, the SFP-8G31-EW transceiver is specifically designed for mission-critical applications that require stable, long-distance, high-speed storage connectivity. Key use cases include:

• Connecting geographically separate Storage Area Networks (SAN)
• Data center to data center disaster recovery links
• Campus-wide SAN extension
• Long-distance 8G/4G/2G Fibre Channel switch-to-switch links
• Server and storage connections in large-scale enterprise environments

Technical Specifications

Advantages

The primary advantage of the SFP-8G31-EW lies in its ability to bridge significant distances without the need for expensive optical amplifiers or signal repeaters. This drastically simplifies network architecture and reduces the total cost of ownership for long-haul SANs. Every module is subjected to rigorous testing to ensure compatibility with leading switch manufacturers like Brocade, Cisco, and others, guaranteeing reliable plug-and-play performance. The integrated DDM (Digital Diagnostics Monitoring) feature further enhances network reliability by providing administrators with the tools to anticipate potential issues before they can impact network performance, ensuring maximum uptime for critical storage applications.

Product & Technical FAQs

1. What does ‘EW’ mean in SFP+ EW?

EW stands for Extended Wavelength, indicating that this SFP+ module is designed for “extended” reach applications. In this case, the SFP-8G31-EW can transmit 8G Fibre Channel signals up to 40km, significantly further than standard LW (Long Wavelength, typically 10km) modules.

2. Is this 8G FC module compatible with a 10G Ethernet SFP+ port?

No. While both use the SFP+ physical form factor, 8G Fibre Channel and 10G Ethernet are different protocols. You must use this module in a host port that specifically supports 8G (or multi-rate 8G/4G/2G) Fibre Channel.

3. Can I use this 40km transceiver for a shorter link, like 5km?

Yes, but it is not recommended without an optical attenuator. The high-power laser designed for 40km can overload the receiver on a very short link, causing errors. For links under 10km, an 8G SFP+ LW module is the more appropriate and cost-effective choice.

4. What is the difference between SFP-8G31-EW and SFP-8G31-LW?

The primary difference is the transmission distance. The EW (Extended Wavelength) version is designed for up to 40km, while the LW (Long Wavelength) version is typically rated for up to 10km. The EW module uses a more powerful laser to achieve this longer distance.

5. Does this module support 1G Fibre Channel?

No, the SFP-8G31-EW is specified for 8G, 4G, and 2G Fibre Channel speeds. It does not support 1G FC rates.

6. What kind of fiber cable is required for this 8G SFP+ EW module?

To achieve the maximum 40km distance, you must use a standard Single-Mode Fiber (SMF) patch cable, such as OS1 or OS2, terminated with LC Duplex connectors.

7. Is this module from a specific brand like Brocade or Cisco?

This is a compatible module, meaning it is manufactured to meet or exceed the specifications of major brands and is programmed to be recognized and function perfectly in devices from OEMs like Brocade, Cisco, Dell/EMC, and others.

8. Why is DDM important for a long-reach transceiver?

DDM (Digital Diagnostics Monitoring) is especially critical for long-reach links as they are more susceptible to signal degradation. DDM allows you to monitor the receive power level in real-time to ensure the signal is strong enough for error-free operation over the entire 40km distance.