Email Us
+86 027-87887588
+86 18971538004

Introduction to 100G QSFP28 Optical Transceiver


In today's landscape, the demand for 100G Ethernet networks is on a steady rise and has become virtually unavoidable. Consequently, there is a growing need for 100G modules. Among the array of 100G optical transceivers available, the QSFP28 100G optical transceiver stands out as the top choice due to its compact size and lower power consumption. In this article, we will provide you with a comprehensive overview of QSFP28 100G transceivers, covering everything you need to know.

100G QSFP28 Definition

A 100G QSFP28, or 100 Gigabit Quad Small Form-Factor Pluggable 28, is a high-speed optical transceiver module designed for data communication and networking applications.

The full name of QSFP28 is Quad Small Form-factor Pluggable Plus 28, which means four-channel small pluggable. The rate of each channel is up to 28Gpbs. These transceivers are widely used in data centers, telecommunications networks, and other high-bandwidth environments to support the rapid exchange of large volumes of data over short and long distances. The QSFP28 form factor ensures compatibility with a wide range of network equipment, making it a popular choice for network administrators and operators aiming to meet the demands of modern, high-performance networks.

QSFP28 100G Module Standards

The standards for the 100G QSFP28 optical module are primarily defined by two key organizations, the IEEE and Multi-Source Agreement (MSA). WHGEARLINK is a professional 100g qsfp28 supplier. The IEEE defines the specifications for the QSFP28 SR4, QSFP28 LR4, and QSFP28 ER4. To clarify these three items from their names, "QSFP" refers to the form factor, "28" indicates a maximum transmission rate of 28Gbps per lane, "SR" stands for short reach with a transmission distance of 100m, "LR" represents long reach with a distance of 10km, and "ER" signifies extended reach with a distance of 40km. The number "4" of ER4 indicates that the module has four lanes. For instance, the QSFP28 LR4 is a long-reach 100G module that can transmit 100G signals over four wavelengths with a transmission distance of 10km.

The most commonly used 100G optical transceiver defined by the IEEE are 100GBASE-SR4 and 100GBASE-LR4. However, the QSFP28 SR4 has a limited transmission distance that might not meet all interconnection requirements, while the cost of the QSFP28 LR4 module is high for large data centers. Therefore, MSA introduced a solution for mid-range connectivity and defined the standards for QSFP28 PSM4 and CWDM4 modules. Although the QSFP28 100G LR4 module can cover the capabilities of QSFP28 CWDM4, the QSFP 100G CWDM4 solution is more cost-effective and competitive for transmission distances of 2km.

QSFP 100G Laser Types

Laser technology is crucial in the functionality of 100G QSFP28 optical transceivers, which are available in five primary types: VCSEL, FP, DFB, DML, and EML. These laser variations exhibit distinct characteristics concerning their operating wavelengths, modes, and suitable usage environments.

Laser TypeWavelengthTransmission Distance
GNQ1M0C85QSFP28 100G 850nm 100m MPO
(100G SR4)
GNQ3L0C31QSFP28 100G 1310nm 10km LC
(100G LR4)
(100G CWDM4)
GNQ5L0C31QSFP28 100G 1310nm 30km LC
(100G ER4)
GNQ2M0C31QSFP28 100G 1310nm 2km MPO
(100G PSM4 2KM)
(100G ZR4 80KM)

100G QSFP28 Transmission Media & Transmission Distances

The 100G QSFP28 optical transceivers come with either LC duplex connectors or MTP/MPO-12 connectors. Their transmission ranges span from 70 meters to 40 kilometers. These transmission capabilities determine the specific use cases for QSFP28 optics. These 100G QSFP28 transceivers are versatile and can be used for direct connections as well as for linking devices within enterprise and data center networks.

QSFP28 100G Transceiver Applications

QSFP28 100G transceivers find a wide range of applications in high-speed data communication networks. Here are some common applications:

Data Centers: QSFP28 transceivers are frequently used in data centers to handle the high-speed connectivity demands of modern cloud computing, storage, and virtualization environments. They are employed for interconnecting switches, routers, and servers within the data center.

Enterprise Networks: These transceivers are suitable for enterprise networks, enabling high-speed data transmission and supporting tasks such as network aggregation, data backup, and interconnecting various network devices.

Telecommunications: In the telecommunications industry, QSFP28 transceivers are used for high-capacity connections, both for short-range and long-range transmission, making them essential for the deployment of 100G networks.

Service Providers: Service providers use QSFP28 transceivers to meet the growing demand for high-bandwidth services, such as 100G Ethernet, in their networks. These transceivers can be used in metro and long-haul networks.

High-Performance Computing (HPC): HPC clusters and supercomputers require high-speed data links to process complex calculations. QSFP28 transceivers provide the necessary bandwidth for fast data transfer within HPC environments.

How to Select the Best 100G QSFP28 Optics?

For distances spanning 5 to 100 meters, you have the option of selecting the QSFP28 SR4 optical transceiver module. It can effectively transmit data up to 70 meters when employing OM3 fibers or extend to 100 meters with the use of OM4 fibers.

If your transmission needs fall within the range of 100 meters to 2 kilometers, it's advisable to consider the suitability of either the QSFP28 100G PSM4 or the QSFP28 CWDM4 modules. It's important to note that while the QSFP28 CWDM4 is notably more expensive than the QSFP28 PSM4, it offers the advantage of utilizing just two single-mode fibers for two-way transmission, which is considerably fewer than the eight single-mode fibers required by the QSFP28 PSM4. Consequently, the total cost of implementing the QSFP28 100G PSM4 can rise significantly. Practical application decisions regarding whether to opt for QSFP28 PSM4 or QSFP28 CWDM4 should be based on the specific interconnection distance.

For transmission distances ranging from 10 to 40 kilometers, you can explore the use of QSFP28 100G LR4, which boasts a maximum transmission range of up to 10 kilometers. Alternatively, china 100g QSFP28 ER4 transceivers can achieve even greater distances, with a maximum transmission capability extending to 40 kilometers.


Can the 100G QSFP28 module be connected downward?

Yes, 100G QSFP28 module can be connected with 25G optical module and 10G optical module. For example, 100G to 4*25G optical module, 100G to10*10G optical module. Branch fiber optic cables are used to connect in the middle.

Are 100G QSFP28 modules compatible with various network equipment manufacturers?

In general, 100G QSFP28 modules are designed to adhere to industry standards set by organizations like the IEEE (Institute of Electrical and Electronics Engineers), which ensures a level of compatibility across different network equipment manufacturers. This means that, in theory, 100G QSFP28 modules should be compatible with a wide range of network equipment from various manufacturers.

What are the power consumption considerations for 100G QSFP28 modules?

Power consumption considerations for 100G QSFP28 modules include module type, operating mode, link length, data rate, standby mode, cooling, power budget, data center efficiency, and future-proofing. Efficient management of power is vital to optimize performance and reduce operational costs.

What types of optical connectors are used with 100G QSFP28 modules?

100G QSFP28 modules commonly use LC duplex or MTP/MPO connectors for optical connections. LC duplex connectors are used for single-mode or multi-mode fiber connections, while MTP/MPO connectors are typically employed for high-density multi-mode fiber connections, especially in data center environments. The choice of connector depends on the specific application and cabling infrastructure.

Gearlink Optical Transceiver
Get in touch with WHGearlink Optical Transceiver Experts to get professional support and helps within 24 hours.
Talk to Us
No.1120, Building 12, Changhang Lanjing International, Hongshan district, Wuhan city, Hubei province, China, 430000.
+86 027-87887588