Views: 599 Author: Addams Publish Time: 2026-04-22 Origin: Site
For data centers, 100G optical modules, as core interconnect devices, have always been a key focus for operators and maintainers in balancing transmission distance and cost. In today's data centers, the QSFP28 CWDM4 optical module, with its unique advantages, is increasingly being chosen by data center builders. Today, let's delve deeper into the 100G QSFP28 CWDM4 optical module and understand why it is so favored by so many data center professionals.
In traditional data centers, before the advent of 100G QSFP28 CWDM4, long-distance connections could only be achieved using 100G QSFP28 LR4. While 100G QSFP28 SR4 was low-cost and consumed little power, its transmission distance was only 100m, making it unsuitable for connecting buildings. Although 100G QSFP28 LR4's 10km transmission distance could meet connectivity requirements, its high cost put pressure on construction funds. Therefore, the need for low-cost mid-range connections led to the development of 100G QSFP28 CWDM4.
Against this backdrop, the CWDM4 MSA organization developed the 100G QSFP28 CWDM4 standard in 2014, providing a precise solution for mid-to-long-distance transmission. The 100G QSFP28 CWDM4, based on Coarse Wavelength Division Multiplexing (CWDM) technology, can achieve a transmission distance of up to 2km using single-mode fiber at a relatively low cost, perfectly filling a market gap and becoming the preferred solution for cross-floor and cross-building interconnection in data centers.
In traditional data centers, interconnection needs are clearly hierarchical, with different products chosen for different levels to achieve better results, seeking a balance between cost and requirements. Within the same building, the connection between servers and aggregation switches is the first layer. This layer involves short connection distances and limited space, making construction and maintenance difficult. Power consumption and heat dissipation also need to be considered. Therefore, DAC connections are typically used at this layer, offering both low cost and low power consumption.
The connection between aggregation switches and core switches is the second layer. This layer involves moderate connection distances, typically not exceeding 100m. Sometimes, backward compatibility with low-speed networks needs to be considered. Therefore, 100G SR4 modules are typically used at this layer, offering both low cost and flexible compatibility with different network speeds.
The connection between different buildings within the data center is the third layer. This layer requires connections across floors and buildings, and in special cases, across data centers. This is the main battleground for 100G CWDM4 optical modules. Compared to MPO, duplex LC fiber is lower in cost, simpler to operate and maintain, and can provide stable and reliable 100G bandwidth transmission over a distance of 2km.
The QSFP28 100G CWDM4 optical module achieves a balance between performance and cost primarily due to its low-cost Coarse Wavelength Division Multiplexing (CWDM) technology. Using this technology, the QSFP28 100G CWDM4 optical module can convert four 25Gbps electrical signals into 25Gbps optical signals with center wavelengths of 1271nm, 1291nm, 1311nm, and 1331nm. These four different wavelength optical signals are then integrated into a single-mode fiber for transmission via a built-in CWDM multiplexer. At the receiving end, the received mixed optical signal is demultiplexed into four independent optical signals by a built-in demultiplexer. These signals are then converted back into electrical signals through conversion and amplification circuitry, achieving a complete 100Gbps transmission.
While the transmission principle appears similar to the QSFP28 100G LR4 optical module, both utilizing wavelength division multiplexing (WDM) technology, the main difference lies in the laser. The QSFP28 100G CWDM4 optical module features a smaller wavelength spacing and higher precision. To maintain this high precision and prevent wavelength shift caused by temperature increases from interfering with the module's normal operation, the QSFP28 100G LR4 laser integrates a TEC cooling circuit to keep its temperature within a standard range.
As for the QSFP28 100G CWDM4 optical module, because CWDM has a 20nm wavelength spacing, it has a high tolerance for wavelength shift and therefore does not require a TEC cooling circuit to assist the laser's operation. This essentially sacrifices precision and system complexity for lower costs. The adoption of uncooled CWDM DFB lasers not only reduces module power consumption (typical power consumption less than 2.6W at commercial-grade temperatures) but also improves equipment stability and lifespan. Regarding performance, there's no need to worry about reduced accuracy impacting performance; the module's built-in forward error correction (FEC) function effectively reduces the bit error rate during transmission, ensuring reliable data transmission over a 2km distance.
As discussed above, compared to the QSFP28 100G LR4 optical module, the QSFP28 100G CWDM4 eliminates the need for high-cost cooled lasers, resulting in lower module procurement costs. Furthermore, the absence of TEC (Transmission Controlled Electron Device) leads to lower power consumption, reducing data center maintenance burden during large-scale deployments and enabling 100G mid-range interconnection at a lower cost, meeting the needs of traditional data centers.
The QSFP28 100G CWDM4 optical module operates within a temperature range of 0~70℃, with industrial-grade products reaching -40~85℃, meeting the complex environments of traditional data center server rooms. Furthermore, the QSFP28 100G CWDM4 optical module incorporates FEC functionality, ensuring signal integrity during long-distance transmission. The module also supports hot-swapping, enabling plug-and-play operation, facilitating equipment maintenance and upgrades, and minimizing disruption to services.
Currently, mainstream brands of 100G switches, servers, and other equipment support the QSFP28 CWDM4 optical module. In addition, YXFiber products undergo rigorous compatibility testing before leaving the factory to ensure seamless integration with equipment from brands such as Cisco, Juniper, and Arista. Therefore, in actual deployment, simply insert two QSFP28 CWDM4 optical modules into the 100G ports of the two devices at each end, and connect them with single-mode dual-core LC fiber patch cords. No complex configuration is required, reducing deployment difficulty and simplifying later maintenance.
Conclusion: YXFiber's QSFP28 100G CWDM4 optical module 2km transmission solution, with its precise market positioning, excellent technical performance, and superior cost control, has become a benchmark solution for long-distance 100G interconnection scenarios in data centers. In today's data centers that continuously pursue efficiency, economy, and reliability, it solves current transmission challenges. Whether you are a data center operator, enterprise IT manager, or network engineer, you can use this optical module to build a stable and efficient long-distance 100G interconnection network, injecting strong momentum into the rapid development of your business.
