Overview
The 100G CWDM4 QSFP28 transceiver module is an advanced optical solution engineered to deliver 100Gbps connectivity over medium distances. It leverages Coarse Wavelength Division Multiplexing (CWDM) technology to transmit four distinct wavelengths of light, each carrying 25Gbps of data, over a standard pair of single-mode fibers. Consequently, this approach eliminates the need for complex parallel fiber cabling associated with short-reach optics.
This technology is standardized by the CWDM4 MSA (Multi-Source Agreement), which ensures interoperability between modules from different vendors. In practical deployments, the QSFP28 CWDM4 module has become the go-to choice for linking switches within data centers or across a campus network, offering a perfect balance of performance, reach, and cost-efficiency where distances exceed multi-mode limits but do not require expensive long-haul optics.
Key Features
- 100Gbps Over Duplex Fiber: Transmits and receives 100G traffic over a standard duplex single-mode fiber cable with LC connectors, simplifying infrastructure.
- Reach Up to 2km: Perfectly suited for interconnects within large data centers, between buildings on a campus, and for metro access links.
- CWDM4 Technology: Utilizes four LAN-WDM wavelengths (around 1310nm) on a duplex fiber, maximizing bandwidth efficiency.
- Low Power Consumption: Engineered for power efficiency (typically under 3.5W), reducing operational costs and thermal load in high-density switches.
- MSA Compliant: Fully compliant with the QSFP28 and CWDM4 MSA standards, guaranteeing compatibility and seamless integration with host equipment.
Applications
The unique capabilities of the 100G CWDM4 QSFP28 module make it ideal for specific, high-impact applications. Its primary use case is in data center interconnects (DCI), especially for spine-to-leaf connections that span multiple rows or halls. Furthermore, it is widely deployed in enterprise campus backbones to link core switches in different buildings. Service providers also utilize these transceivers in their edge networks for high-bandwidth aggregation links that fall within the 2km range.
Specifications
| Parameter | Value |
|---|---|
| Form Factor | QSFP28 |
| Data Rate | 103.1 Gbps to 112 Gbps |
| Technology | Coarse Wavelength Division Multiplexing (CWDM) |
| Wavelengths | 1271nm, 1291nm, 1311nm, 1331nm |
| Maximum Reach | 2km |
| Fiber Type | Single-Mode Fiber (SMF) G.652 |
| Connector Type | Duplex LC |
| Compliance | IEEE 802.3bm (100GBASE-CWDM4), CWDM4 MSA |
| Host FEC Requirement | Required (Forward Error Correction) |
Advantages
The foremost advantage of the CWDM4 QSFP28 module is its exceptional cost-efficiency for medium-reach 100G links. In contrast to short-reach SR4 modules that require expensive MPO/MTP parallel fiber cabling, CWDM4 operates on the same standard duplex LC cabling used for 10G and 25G. This significantly reduces infrastructure costs and simplifies migration. Moreover, it offers a more economical solution than 100GBASE-LR4 transceivers.
While LR4 modules are designed for 10km, they are often overkill and too expensive for common 500m to 2km links inside a data center. The 100G CWDM4 transceiver perfectly fills this critical gap, providing the necessary reach without the associated cost premium. As a result, network architects can deploy 100G connectivity precisely where needed without overspending on an over-engineered solution.
FAQ (Technical & product category Questions)
1. What exactly is a 100G CWDM4 QSFP28 module?
A 100G CWDM4 QSFP28 is an optical transceiver that transmits 100Gbps data by using four different wavelengths (colors) of light over a single pair of single-mode fibers. It uses the QSFP28 form factor and is designed for distances up to 2 kilometers, making it ideal for data center interconnects.
2. What is the difference between a CWDM4 and an LR4 QSFP28 module?
The main difference is reach and cost. The CWDM4 QSFP28 module is specified for a reach of up to 2km and is more cost-effective. In comparison, the 100GBASE-LR4 module is designed for a much longer reach of up to 10km and is therefore a more expensive optical transceiver.
3. What kind of fiber cable do I need for a CWDM4 transceiver?
You need a standard single-mode fiber (SMF) patch cable with Duplex LC connectors. This is a significant advantage as it is the same type of cable commonly used for 10G-LR or 25G-LR optics, simplifying cabling infrastructure.
4. Is a 100G CWDM4 module compatible with a 100G SR4 module?
No, they are not compatible. A CWDM4 module uses four wavelengths over single-mode fiber with an LC connector. A 100G SR4 module uses four parallel fibers within a multi-mode MPO connector. You cannot directly connect these two different types of optical transceivers.
5. Does the CWDM4 QSFP28 module require FEC?
Yes, Forward Error Correction (FEC) is required on the host device (switch, router) for a 100G CWDM4 link to function correctly. FEC is a mechanism that detects and corrects bit errors in the data stream, which is essential for ensuring reliable performance at 100Gbps speeds over 2km.
6. What are the four wavelengths used in a CWDM4 module?
A standard CWDM4 QSFP28 transceiver operates on four wavelengths from the LAN-WDM grid: 1271nm, 1291nm, 1311nm, and 1331nm. Each of these channels carries a 25Gbps signal.
7. Can I use a CWDM4 module for a link shorter than 2km?
Absolutely. The 2km rating is the maximum guaranteed distance. These optical transceivers will work perfectly for any shorter link over single-mode fiber, such as 500 meters or 1 kilometer, making them very flexible for various campus and data center scenarios.
8. Why choose a CWDM4 module instead of two 40G links?
Choosing a single 100G CWDM4 module provides higher bandwidth in a single port, simplifies network management, and often has a lower total cost and power consumption compared to deploying two separate 40G links. It provides a more streamlined path for future network scaling.
100G CWDM QSFP28 Transceiver
Cisco Compatible 100G QSFP28 CWDM4 Transceiver: Reach 2km on Single Fiber
Overview: The 100G CWDM QSFP28 optical transceiver is a high‑performance, energy‑efficient solution for 100 Gigabit Ethernet and data center interconnect applications. It transmits 100 Gbps aggregate bandwidth through four lanes of 25 Gbps each using Coarse Wavelength Division Multiplexing (CWDM) technology in the 1270–1330 nm spectrum range. Fully compliant with QSFP28 MSA and IEEE 802.3ba/802.3bm standards, the module provides optimized port density and low power consumption for next‑generation switches and routers.
Technical Specifications
- Form Factor: QSFP28 (4 × 25 Gbps lanes)
- Data Rate: 100 Gbps aggregate
- Wavelengths (CWDM grid): 1271 nm, 1291 nm, 1311 nm, 1331 nm
- Reach Options: up to 2 km over SMF (CWDM4) / up to 10 km over SMF (LR4)
- Connector Interface: Duplex LC
- Fiber Type: Single‑Mode Fiber (SMF)
- Power Consumption: ≤ 3.5 W typical
- DDM/DOM Monitoring: Supported via I²C interface (CMIS 4.0 compliant)
- Operating Temperature: 0 °C to 70 °C (standard) / ‑5 °C to 85 °C (industrial option)
- Compliance: IEEE 802.3bm 100GBASE‑CWDM4/LR4, QSFP28 MSA, CWDM MSA, CMIS 4.0, RoHS 6/6
Main Features
- Hot‑pluggable QSFP28 MPO or LC form factor for 100 Gigabit Ethernet ports
- 4 × 25 Gbps CWDM lanes enable efficient 100 Gbps optical transmission
- Low power design (≤ 3.5 W) reduces data center thermal loads
- Supports Digital Diagnostics Monitoring for real‑time link performance
- Interoperable with IEEE 802.3bm/ba and CWDM4 Alliance compliant products
- Standard Duplex LC connector and 2 km SMF reach for optimized fiber utilization
- Ideal for aggregation and inter‑rack connections in cloud and metro networks
- Available in industrial temperature range versions for carrier applications
Applications
- 100 Gigabit Ethernet (100GBASE‑CWDM4/LR4) network uplinks
- Data center aggregation and core switch interconnects
- Cloud service provider and HPC network topologies
- 5G backhaul, metro edge, and enterprise fiber links
- Client‑side optics for DWDM or ROADM systems
Related Keywords: 100G CWDM QSFP28 module, 100GBASE‑CWDM4 optical transceiver, 100G CWDM LC transceiver, 100G single‑mode CWDM module, low‑power 100G QSFP28 optic, Mefiber 100G CWDM QSFP transceivers.
FAQ – 100G CWDM QSFP28 Optical Transceivers
1. What is a 100G CWDM QSFP28 module?
It’s a compact optical transceiver using four CWDM wavelengths (1271–1331 nm) to deliver a 100 Gbps aggregate signal over single‑mode fiber.
2. What standards and protocols does it support?
It complies with IEEE 802.3bm 100GBASE‑CWDM4, QSFP28 MSA, and CWDM MSA specifications, ensuring vendor interoperability.
3. How far can the 100G CWDM QSFP transmit?
CWDM4 modules reach up to 2 km over SMF, while long‑reach types (LR4) extend distances to 10 km.
4. What connector type is used?
The 100G CWDM QSFP uses a standard duplex LC optical connector for simple fiber management.
5. What is the power consumption of a 100G CWDM QSFP28?
Each module typically consumes ≤ 3.5 W, making it an energy‑efficient choice for dense data center deployments.
6. Does it support Digital Diagnostics Monitoring (DDM/DOM)?
Yes, it supports I²C‑based DOM/DDM for monitoring temperature, voltage, bias current, and optical power.
7. In which environments can it operate?
Modules are available for standard (0 °C to 70 °C) and industrial (‑5 °C to 85 °C) temperature ranges.
8. How does CWDM QSFP differ from LR4 or SR4 modules?
CWDM QSFP uses coarse wavelengths for medium reach (2‑10 km), SR4 uses parallel optics for short reach (MMF up to 100 m), and LR4 is optimized for 10 km SMF links.