The Evolution of Fiber Connectivity: From Pluggable Optics to Co-Packaged Optics (CPO)

The Limitations of Pluggable Transceivers

As data centers and high-performance computing environments push the boundaries of network speeds, traditional pluggable transceivers are reaching their physical and electrical limitations. The use of electrical traces on printed circuit boards (PCBs) introduces signal integrity challenges, power consumption concerns, and increased latency. These constraints become more pronounced as transmission speeds climb beyond 800Gbps, prompting the need for new, more efficient optical connectivity solutions.

 

A Gradual Transition: From Pluggable Optics to CPO

The shift from traditional pluggable optics to Co-Packaged Optics (CPO) is not an abrupt leap but a structured and phased progression that enables incremental improvements in bandwidth, power efficiency, and signal integrity. This transition represents a fundamental shift in how fiber is integrated into networking infrastructure, moving ever closer to the chip to enable higher bandwidth, lower latency, and improved efficiency. A key study by Yole Développement (March 2022) maps this shift, showing how power efficiency and system complexity drive the adoption of CPO over time.

At this stage, optical connectivity remains external, with the Multi-Fiber Push-on (MPO) connector embedded inside pluggable transceivers. Electrical traces on PCBs continue to be used for data transmission, from the transceiver through the PCB to the ASIC, contributing to power consumption and latency issues. While pluggable optics remain viable up to 800Gbps, the growing demand for higher speeds necessitates more advanced integration approaches.

 

On-Board Optics for up to 1.6Tbps

To mitigate the limitations of pluggable transceivers, on-board optics move optical transceivers directly onto the PCB. This reduces the length of electrical traces, improving thermal performance and enhancing signal integrity. The MPC PIC now resides directly on the board, allowing for increased density and improved power efficiency. This step lays the foundation for future advancements by minimizing electrical interconnect challenges.

 

Co-Packaged Optics (CPO) on Substrate for 3.2Tbps and Beyond

CPO represents a significant leap forward, integrating optics directly onto the switch substrate. By eliminating nearly all electrical traces, CPO drastically reduces power consumption and latency while enhancing signal integrity. This co-packaged approach allows for higher bandwidth capabilities and paves the way for even greater scalability in next-generation data centers.

 

Direct Optical I/O for 6.4Tbps and Above

The final phase of fiber connectivity evolution introduces direct optical I/O, where optical fibers are directly coupled to the switch chip itself. This removes the need for electrical interconnects altogether, further optimizing power efficiency, bandwidth, and overall system performance. This architecture is critical for meeting the demands of future AI, machine learning (ML), high-performance computing (HPC), and hyperscale data center applications.

Why This Transition Matters

The demand for higher bandwidth, lower power consumption, improved signal integrity, and future-proof scalability is driven by Artificial Intelligence (AI), Large Language Models (LLMs), Machine Learning (ML), High-Performance Computing (HPC), and Hyperscale Data Centers. As workloads become more data-intensive, traditional electrical interconnects struggle to keep up with the required performance. Transitioning from pluggable optics to CPO and eventually to direct optical I/O is essential for supporting the next generation of networking and computing applications. This shift ensures:

• Higher bandwidth to accommodate exponential data growth by reducing the distance signals travel in the electrical domain.
• Lower power consumption by reducing electrical interconnect losses and heat generation.
• Improved signal integrity through direct optical coupling which minimizes signal degradation, boosting efficiency.
• 可扩展性 for future applications requiring even higher data rates with the optical I/O at the chip level.

 

SENKO’s Role in the Future of Optical Connectivity

SENKO is at the forefront of optical connectivity innovation, providing advanced solutions that facilitate the transition from pluggable transceivers to next-generation optical architectures. Their pioneering products include:

• MPC Connectors – Enabling high-density optical connectivity for emerging on-board and co-packaged applications. MPC is designed for direct fiber-to-the-chip coupling, reducing losses and increasing efficiency.
• SN-MT and MPO Bayonet Connectors – Designed for compact, high-performance and high-density interconnects in next-generation data centers, offering superior space saving features.
• ELSFP (Enhanced Large-Scale Form-Factor Pluggable) – A future-ready solution addressing the power and density requirements of next-gen transceivers. ELSFP supports evolving hyperscale data center architectures, providing high bandwidth and low power consumption.
• Advanced Optical Backplane Solutions – SENKO is also pioneering new backplane optical connectivity options, ensuring seamless high-speed data transmission within critical infrastructure environments.

By continuously innovating in optical connectivity, SENKO is helping data centers and high-performance computing environments achieve higher throughput, lower latency, and greater efficiency. As the industry progresses toward higher-speed optical solutions, SENKO’s innovations play a crucial role in ensuring seamless scalability, enhanced performance, and future-proof connectivity for AI-driven and hyperscale environments.

 

结论

The evolution from pluggable optics to CPO and direct optical I/O represents a critical advancement in fiber connectivity. By progressively integrating optics closer to the switching fabric, this transition addresses the growing needs of AI, ML, HPC, and hyperscale data centers. With companies like SENKO leading the charge in optical connectivity solutions, the future of high-speed networking is poised for remarkable breakthroughs that will redefine data center architectures and performance benchmarks.