Cisco 100GBASE CWDM4 QSFP Transceiver — LC, 2km Over SMF

The Cisco 100GBASE CWDM4 QSFP Transceiver is a high-performance optical module designed for modern data centers and enterprise networks that demand scalable, reliable, and flexible 100 Gigabit Ethernet connectivity. Engineered to support the 100GBASE-CWDM4 standard, this transceiver delivers four parallel 25 Gbps lanes over a single-mode fiber (SMF) link, enabling efficient aggregation and interconnects across campus and data-center fabrics. With an LC duplex connector and a 2-kilometer reach, it provides a robust solution for mid-range distances while preserving port density in space-constrained environments. Built on Cisco’s trusted quality and interoperability, this transceiver is optimized for use in Cisco switches, routers, and line cards that support CWDM4 QSFP28 modules, offering a seamless upgrade path to 100G where fiber availability and budget require it.

• High-density 100GBASE-CWDM4 performance: Four 25 Gbps lanes driven by CWDM wavelengths enable scalable, cost-efficient 100G connectivity over SMF for data-center interconnects and uplinks.
• Compact QSFP28 form factor with LC duplex connector: A hot-pluggable module designed to maximize port density in existing Cisco devices while maintaining easy fiber termination with standard LC connectors and duplex SMF cables.
• Distance and fiber compatibility: Engineered for up to 2 km over single-mode fiber, delivering reliable reach for data-center consolidation, mid-range interconnects, and campus networks without requiring more expensive longer-reach solutions.
• Built for reliability and ease of deployment: Cisco’s transceivers are designed for interoperability with Cisco platforms, featuring robust electro-optical performance, Digital Optical Monitoring (DOM) support where available, and a plug-and-play approach that minimizes deployment time.
• Power efficiency and management: Optimized power usage and thermal performance to reduce cooling requirements in dense data-center racks, while offering straightforward maintenance and monitoring via supported management interfaces.

Technical Details of Cisco 100GBASE CWDM4 QSFP Transceiver

• Standard: 100GBASE-CWDM4
• Form factor: QSFP28
• Connector: LC duplex
• Medium: Single-Mode Fiber (SMF)
• Reach: Up to 2 km
• Channels: Four CWDM wavelengths delivering 4x25 Gbps lanes
• Wavelengths: CWDM4 channels within the ITU CWDM grid (specific center wavelengths are vendor-implementation dependent)
• Data rate: 100 Gbps aggregate
• Diagnostics: Digital Optical Monitoring (DOM) support on compatible platforms
• Compatibility: Cisco devices and other platforms that support CWDM4 QSFP28 modules; designed for interoperability within Cisco ecosystems
• Operating environment: Typical data-center-temperature ranges with RoHS-compliant materials
• Installation: Hot-swappable; requires compatible Cisco line cards or switches

How to Install Cisco 100GBASE CWDM4 QSFP Transceiver

• Power down the affected switch or line-card slot according to your vendor’s guidelines before insertion.
• Remove any existing transceiver from the QSFP28 port and inspect the slot for cleanliness and obstructions; handle the module by its edges.
• Align the transceiver with the slot and gently insert until you hear a subtle click and the module is firmly seated.
• Connect a duplex LC SMF fiber cable to the LC connector on the transceiver, ensuring proper polarity and minimal bend radius to protect fiber integrity.
• Power up the device and verify link status via the switch’s user interface or CLI; confirm 100G link aggregation is established and DOM data (if available) is reporting healthy metrics.

Frequently asked questions

• Q: What networks is this transceiver suitable for?

  A: It is ideal for data-center interconnects, uplinks between leaf and spine layers, server access uplinks, and other scenarios requiring 100G Ethernet over SMF with a 2 km reach. It is designed to work within Cisco ecosystems and compatible devices that support CWDM4 QSFP28 modules.

• Q: Will this module work with non-Cisco switches?

  A: Compatibility depends on the vendor’s support for CWDM4 QSFP28 multi-rate modules. While many switches from other vendors support CWDM4, you should verify the specific model’s transceiver compatibility matrix and firmware requirements before deployment.

• Q: Does it support digital optical monitoring (DOM)?

  A: DOM support is commonly available on compatible platforms, enabling real-time monitoring of optical parameters such as input/output power, temperature, and activity. Check your device’s documentation to enable and read DOM data.

• Q: How do I ensure the correct fiber polarity and cabling?

  A: Use a standard duplex SMF fiber pair with LC connectors. Maintain proper polarity by ensuring Tx is connected to Rx on the corresponding port and adhere to the fiber type and bend-radius guidelines specified by your fiber cabling standard.

• Q: What maintenance or replacement considerations exist?

  A: Treat the transceiver as a hot-pluggable component; avoid touching optical surfaces. Regularly inspect fiber connections for cleanliness, and replace the module if a degraded optical signal or persistent link instability occurs after verified cabling checks.

• Q: How do I verify 100G performance after installation?

  A: Confirm the 100G link status on the switch, review error counters and interface statistics, and use a traffic generator or benchmark tool to validate throughput, latency, and packet loss within expected ranges for your environment.