100G QSFP28 DCO Market Outlook: Trends, Applications, and the Evolution of 800G DCO

1. Introduction

Driven by the rapid growth of AI foundation model training, cloud computing, hyperscale data centers, and carrier backbone networks, network bandwidth is evolving rapidly from 100G to 400G, 800G, and eventually 1.6T. At the same time, increasing demands for higher bandwidth, longer transmission distances, and greater network reliability are accelerating the deployment of Data Center Interconnect (DCI), metropolitan area networks (Metro), and long-haul optical transport networks. As a result, Digital Coherent Optics (DCO) has become one of the most important technologies enabling next-generation high-speed optical transmission.

However, the emergence of 800G DCO does not signal the end of 100G DCO. Instead, these two technologies address different network layers and application requirements. Over the coming years, they will continue to coexist, complement each other, and evolve together to support diverse network architectures.

As a leading provider of high-speed optical networking solutions, C-LIGHT continues to expand its Digital Coherent Optics portfolio. The company now offers comprehensive 100G QSFP28 DCO and 800G DCO product families for carrier networks, Data Center Interconnect (DCI), and AI infrastructure. Available in both QSFP-DD and OSFP form factors, these coherent optical transceivers provide flexible, reliable, and long-distance transmission solutions for networks of every scale.

DCO 800G/400G/200G/100G DWDM Coherent Transceiver丨C-LIGHT

2. What Is Digital Coherent Optics (DCO)?

Digital Coherent Optics (DCO) integrates a high-performance digital signal processor (DSP), a tunable laser, a coherent receiver, and advanced digital compensation algorithms into a standard pluggable optical transceiver. This highly integrated architecture enables high-speed optical transmission over distances ranging from tens to hundreds of kilometers—and even beyond.

Compared with conventional gray optics, Digital Coherent Optics provides several significant advantages:

• Higher spectral efficiency

• Superior chromatic dispersion compensation

• Longer transmission reach

• Enhanced link monitoring and performance visibility

• Lower overall network deployment cost

• Native support for DWDM transmission

These advantages have made DCO the preferred technology for carrier transport networks, Data Center Interconnect (DCI), metropolitan area networks (Metro), and backbone DWDM infrastructures.

The C-LIGHT 100G QSFP28 DCO integrates a high-performance coherent DSP, tunable DWDM laser, and advanced digital signal processing technologies into a compact QSFP28 form factor. Designed for DWDM deployment, it is ideally suited for OTN, Metro, DCI, and carrier metropolitan networks, delivering highly reliable 100G coherent transmission over long distances.

3. Why Does 100G DCO Still Have Strong Market Potential?

Although industry attention is increasingly focused on 800G networking, 100G DCO continues to enjoy stable and growing market demand across many networking scenarios.

3.1 A Massive Installed Base of Existing Networks

A significant portion of carrier infrastructure worldwide is still built upon 100G OTN, 100GbE, and DWDM architectures. Standard 100G QSFP28 optical ports remain widely deployed across carrier switches, enterprise switches, routers, and next-generation FTTH OLT platforms supporting XGS-PON, 25G PON, and 50G PON.

Rather than replacing existing infrastructure overnight, most operators will continue expanding their installed networks over the coming years. Consequently, 100G DCO will remain a critical technology for network expansion and capacity upgrades.

3.2 Mature Technology with Lower Deployment Costs

After years of commercial deployment, 100G QSFP28 DCO has become a highly mature and cost-effective solution, offering:

• Broad compatibility with mainstream switches, routers, and OLT platforms

• Proven and mature coherent DSP technology

• Simplified DWDM network deployment

• Lower procurement costs

• Reduced power consumption

For small- and medium-scale DCI projects, enterprise private networks, and regional interconnection applications, 100G DCO continues to deliver an excellent balance between cost and performance.

3.3 Ideal for Numerous Medium- and Low-Capacity Applications

Not every network requires 800G bandwidth.

Many applications continue to rely on 100G connectivity, including:

• Enterprise leased-line services

• Metro aggregation networks

• Edge data centers

• Financial networks

• Government networks

• Education and research networks

For these scenarios, 100G DCO provides the optimal balance of cost, power efficiency, and transmission performance.

To address the growing demand for 100G coherent networking, the C-LIGHT 100G QSFP28 DCO features a low-power architecture while maintaining carrier-grade reliability and long-term product availability. It is well suited for enterprise leased lines, regional Data Center Interconnect (DCI), and DWDM network expansion, helping customers maximize transmission performance while minimizing total investment costs.

4. 800G DCO: The New Growth Engine for the AI Era

As AI GPU clusters continue to expand, enormous volumes of training data, model parameters, and inference traffic must be exchanged between geographically distributed data centers.

Compared with 100G solutions, 800G Digital Coherent Optics delivers substantial advantages, including:

• Eight times higher bandwidth

• Greater spectral efficiency

• Lower power consumption per transmitted bit

• Higher port density

• Lower cost per bit

As a result, 800G DCO is becoming a key enabling technology for next-generation AI Data Center Interconnect (AI DCI).

Typical deployment scenarios include:

• AI Data Center Interconnect (AI DCI)

• Hyperscale cloud infrastructure

• Metro backbone upgrades

• Next-generation OTN transport networks

• 800G DWDM systems

Designed for next-generation AI infrastructure, the C-LIGHT 800G DCO QSFP-DD and 800G DCO OSFP product families integrate high-performance coherent DSPs, tunable DWDM lasers, and advanced digital signal processing technologies to meet the demanding requirements of AI data centers, hyperscale cloud networks, and high-capacity DWDM transport systems, delivering exceptional bandwidth, long-distance transmission, and energy efficiency.

5. 100G DCO and 800G DCO Are Complementary Rather Than Competitive

Many people assume that 800G networking will eventually replace 100G entirely. In reality, this assumption overlooks the layered evolution of modern network architectures.

Future networks will continue adopting a hierarchical deployment model, with different coherent transmission technologies serving different network tiers.

In this architecture, 100G DCO provides economical and wide-scale deployment, while 800G DCO delivers ultra-high-capacity transport for next-generation backbone and AI networks. Both technologies will coexist for many years.

For most carriers and enterprise customers, network modernization is typically implemented through a phased migration strategy rather than a complete infrastructure replacement. C-LIGHT recommends a layered deployment approach: continue leveraging the mature and reliable 100G DCO at the edge and access layers while gradually introducing 800G DCO into core data centers, AI computing clusters, and backbone transport networks. This strategy effectively balances investment protection, network performance, and long-term scalability.

6. C-LIGHT Digital Coherent Optics Portfolio

To meet the diverse requirements of carriers, cloud service providers, and enterprise customers, C-LIGHT has developed a comprehensive Digital Coherent Optics portfolio covering multiple transmission rates and deployment scenarios.

C-LIGHT 100G QSFP28 DCO

The C-LIGHT 100G QSFP28 DCO is designed for carrier transport networks, metro aggregation, and Data Center Interconnect (DCI), delivering highly reliable long-distance coherent transmission in a compact QSFP28 form factor.

Key Features

• Standard QSFP28 pluggable form factor

• High-performance coherent DSP

• Tunable DWDM laser

• High optical output power up to +3 dBm

• Optimized for long-reach Metro and DCI applications

• Low-power architecture

• Supports Open Optical Networking

• Carrier-grade reliability for continuous operation

• Customizable CMIS or SFF-8636 management interface

Typical Applications

• Metro Networks

• Data Center Interconnect (DCI)

• OTN Transport Networks

• DWDM Transmission Systems

• Enterprise Private Networks

• Regional Backbone Networks

C-LIGHT 800G DCO

The next-generation C-LIGHT 800G DCO product family, available in QSFP-DD and OSFP form factors, is purpose-built for AI data centers, hyperscale cloud infrastructure, and next-generation carrier optical transport networks.

Key Features

• 800Gbps coherent transmission

• Standard QSFP-DD and OSFP form factors

• High-performance coherent DSP

• Tunable DWDM laser

• Supports ZR+ and OpenZR+ applications

• Optimized for AI Data Center Interconnect (AI DCI)

• Designed for carrier Metro networks

• Highly integrated architecture

• Optimized thermal management

• Lower power consumption per transmitted bit

Typical Applications

• AI Data Centers

• Cloud Data Center Interconnect

• Metro DWDM Networks

• OTN Backbone Networks

• Regional Backbone Networks

• Open Optical Networks

7. How Should 100G and 800G DCO Be Deployed Together?

Network evolution rarely involves replacing every component simultaneously. Instead, most operators and enterprises adopt a phased migration strategy that protects existing investments while enabling future scalability.

A typical deployment architecture includes:

• Continue using 100G DCO at edge and access nodes.

• Upgrade Metro aggregation networks to 400G DCO where higher capacity is required.

• Deploy 800G DCO in AI core data centers and hyperscale cloud environments.

• Utilize 800G and higher-speed coherent optics for national backbone and long-haul transport networks.

This layered approach enables network operators to maximize the value of existing infrastructure while supporting future traffic growth.

As a result, 100G DCO and 800G DCO will coexist for many years, operating seamlessly within unified OTN and DWDM transport platforms.

C-LIGHT provides both 100G QSFP28 DCO and 800G DCO solutions, allowing customers to deploy the appropriate coherent technology at each network layer while ensuring a smooth migration path toward 400G, 800G, and eventually 1.6T optical networks.

8. Future Market Trends

The Digital Coherent Optics market is expected to continue expanding rapidly over the coming years, driven by AI infrastructure, cloud computing, and carrier network modernization.

Key industry trends include:

• AI infrastructure accelerating adoption of 800G DCO

• Continued demand for 100G DCO in carrier networks

• Edge nodes and OLT uplinks remaining major deployment scenarios

• Further convergence of OTN and IP networking

• Higher integration and lower power consumption in coherent modules

• Commercialization of 1.6T coherent optics

The industry is evolving toward a balanced roadmap characterized by:

• Stable growth of 100G DCO

• Continuous expansion of 400G DCO

• Rapid adoption of 800G DCO

• Emerging commercialization of 1.6T coherent optics

As AI infrastructure continues to evolve, coherent optical technology will become a foundational component of future carrier networks and cloud-scale data centers.

C-LIGHT will continue expanding its coherent optics roadmap with comprehensive 100G, 400G, 800G, and future 1.6T DCO solutions, providing global carriers and cloud service providers with scalable, future-ready optical networking technologies.

9. Why Choose C-LIGHT Digital Coherent Optics?

C-LIGHT is committed to advancing high-speed coherent optical technologies for carrier networks, cloud service providers, internet companies, and AI data centers.

Advantages of C-LIGHT Digital Coherent Optics

• Complete portfolio covering 100G and 800G DCO

• Standard QSFP-DD and OSFP form factors

• Designed for OTN, DWDM, DCI, and AI Data Centers

• Integrated high-performance coherent DSP and tunable laser technology

• Optimized thermal design with low-power architecture

• Support for Open Optical Networking

• Broad compatibility with mainstream switches, routers, and optical transport platforms*

• OEM and ODM customization services

• Professional pre-sales consulting and technical support

*Compatibility may vary depending on the target platform model and software version.

10. Conclusion

Rather than competing technologies, 100G DCO and 800G DCO are complementary solutions designed for different network layers and application requirements.

Over the next decade, 100G DCO will continue serving enterprise networks, metropolitan networks, regional Data Center Interconnect (DCI), and carrier transport infrastructure, while 800G DCO will become the preferred solution for AI data centers, hyperscale cloud computing, and next-generation backbone networks.

By continuously expanding its portfolio of coherent optical products, C-LIGHT is committed to delivering flexible, high-performance, and future-ready Digital Coherent Optics solutions that help carriers, cloud providers, and enterprise customers build scalable, energy-efficient optical transport networks.

Looking ahead, 100G, 400G, 800G, and eventually 1.6T Digital Coherent Optics will evolve together to support the next generation of intelligent optical networking. Leveraging extensive expertise in coherent transmission technologies, C-LIGHT will continue driving innovation across its DCO portfolio, empowering global customers to build higher-bandwidth, lower-power, and future-proof optical infrastructures.

11、C-LIGHT Digital Coherent Optics Portfolio

12、Frequently Asked Questions (FAQ)