100G QSFP28 CWDM4 Optical Transceiver Module - Reliable 2km

In this review the focus is on a practical 100G QSFP28 CWDM4 optical transceiver module that targets network engineers and data center teams needing a cost-effective single-mode 100G link. The reviewer found it delivers the expected 100GBASE-CWDM4 performance over up to 2km with a standard LC connector and hot-pluggable QSFP28 form factor. For anyone deploying 100G to 4x25G breakout applications or replacing modules in mixed-vendor environments, this module stands out for compatibility, low power draw and a sensible commercial temperature range.

Key Features

• 100GBASE-CWDM4: Provides four wavelengths (1271nm, 1291nm, 1311nm, 1331nm) for reliable 100G single-mode links up to 2km, minimizing fiber changes.
• QSFP28 MSA Form Factor: Hot-pluggable design simplifies installation and maintenance in rack environments without powering down switches or servers.
• Low Power Consumption: Typical power around 3.5W helps keep module heat and rack power budgets manageable for dense installations.
• DOM Support: Digital optical monitoring lets technicians check real-time optical parameters for faster troubleshooting and preventative maintenance.
• Breakout Capability: Supports 100G to 4x25G breakout use cases, offering flexibility when connecting to 25G-capable equipment.
• Standards Compliance: Built to IEEE 802.3ba and ITU-T G.694.2 conventions for predictable interoperability with other CWDM4 equipment.

Who It's For

This module is best for network administrators and systems integrators building or expanding 100G single-mode links within campuses or data centers that require up to 2km reach. It is particularly useful when a low-power, hot-pluggable transceiver with DOM and breakout support is needed to simplify mixed-rate deployments.

Those who should look elsewhere include users needing multimode optics, longer than 2km single-mode reach, or modules specified for extended temperature ranges beyond the commercial 0 to 70C window. If you require vendor-specific firmware identification guarantees, verify compatibility with your switch vendor first.

Pros & Cons

Pros

• Supports CWDM4 wavelengths and 2km single-mode reach, enabling straightforward 100G links over existing fiber.
• Hot-pluggable QSFP28 design with low 3.5W power consumption reduces downtime and thermal load in dense racks.
• DOM support and standards compliance aid monitoring and interoperability across equipment from different vendors.
• Breakout to 4x25G adds practical flexibility for mixed-rate networks.

Cons

• Commercial temperature rating (0 to 70C) may not suit outdoor enclosures or harsh environments.
• Not intended for multimode or longer than 2km applications, limiting use to single-mode short reach links.

Specifications

Form Factor	QSFP28 MSA
Data Rate	100GBASE-CWDM4
Wavelengths	1271nm, 1291nm, 1311nm, 1331nm
Maximum Reach	2km (single-mode)
Connector	LC, full-duplex
Power Consumption	Approximately 3.5W
Operating Temp	0 to 70C (32 to 158F)

Our Verdict

This 100G QSFP28 CWDM4 transceiver is a practical choice for data center and enterprise teams needing a reliable 100G single-mode link with breakout support and low power consumption. It represents good value when the deployment fits within the 2km reach and commercial temperature limits, offering straightforward interoperability and monitoring features that reduce maintenance time.

Frequently Asked Questions

Can this module support 100G to 4x25G breakout?
Yes, the transceiver supports 100G to 4x25G breakout applications, enabling connections to 25G-capable ports where needed.

What form factor and connector does it use?
It uses a QSFP28 MSA hot-pluggable form factor with LC full-duplex connectors for single-mode fiber.

What is the operating temperature range?
The module is rated for a commercial operating range of 0 to 70C (32 to 158F), suitable for typical indoor rack environments.