Exploring the Advantages of 200G (8x25G NRZ) Optical Technology in Data Centers

GIGALIGHT, which has focused on optical communication for eight years, directs your attention to the 200G (8x25G NRZ) technology, delving into its advantages such as low power consumption, low latency, and easy deployment. This provides a deeper understanding of cost-effective optical interconnection solutions within data centers.

There are two technological directions for 200G optical modules: one utilizes the QSFP-DD packaging for an economical 8x25G NRZ network, while the other employs QSFP56 packaging for a 4x50G PAM4 network (to be discussed in a subsequent article).

Compared to PAM4 technology, 200G (8x25G NRZ) boasts advantages in low power consumption, low latency, and easy deployment.

Technical details:

QSFP-DD packaging for 8x25G NRZ network: The 200G optical module uses QSFP-DD packaging, transmitting 25G NRZ signals through 8 channels. NRZ, representing non-return-to-zero signals, involves signal switching between high and low levels. Compared to traditional PAM4 signals, NRZ signals are easier to modulate and demodulate.

Low power consumption: Utilizing 25G NRZ optical components, the module’s power consumption is reduced by 2–3W compared to modules based on PAM4 DSP CDR technology. This offers significant advantages for data center operational costs (OPEX) and cooling efficiency.

Low latency: 200G NRZ excels in special application scenarios with stringent network latency requirements, such as high-frequency trading networks. The transmission method of NRZ signals provides an advantage in terms of latency.

Deployment ease:

Mature industry chain: The technology of 25G NRZ optical chips and components is relatively mature, providing a reliable foundation for the production of 200G NRZ. This makes the development of related 200G switch ports and optical module products relatively easy, facilitating rapid commercial deployment.

Low-cost optical interconnection: Due to mature technology and industry chains, 200G NRZ achieves low-cost optical interconnection within data centers. This offers an economically effective solution for the construction and expansion of large-scale data centers.


The 200G QSFP-DD SR8 is a multimode parallel product, utilizing an 8-channel 850nm VCSEL array, compliant with the 100GBASE-SR4 protocol standard. Leveraging the advantages of traditional VCSEL platforms, GIGALIGHT has adopted a simple, efficient, and reliable fiber coupling process. By introducing a 45° prism between the laser and the fiber, along with special material treatment on the fiber surface, the fiber coupling efficiency has been increased to over 80%.


The 200G QSFP-DD PSM8 is a high-speed product utilizing single-mode parallel technology. In comparison to wavelength division multiplexing (WDM) technology, PSM technology offers cost advantages. GIGALIGHT PSM optical module enables error-free long-distance transmission up to 10km, five times the distance achieved by traditional PSM optical modules.


The 200G QSFP-DD LR8 optical module is based on an 8-channel LAN-WDM wavelength division multiplexing design, achieving a 1E-12 bit error rate over a transmission distance of 20km. In the context of high-reliability 5G middle-backhaul transmission systems, the long-term transmission of PAM4 signals may pose challenges such as insufficient bandwidth. The 200G QSFP-DD LR8, however, offers a high-performance, low-latency, and highly reliable channel solution.

GIGALIGHT has recently made significant strides in optical design, particularly achieving notable success in the development of 800G optical modules. The design includes the completion of 800G SR8/DR8. For more details, please refer to here. Moreover, GIGALIGHT has successfully mass-produced and deployed 8-channel optical products in niche markets globally, encompassing various fields such as 200G, 400G, and 800G. Visit our official website for further information.