Industry Debates CPO Readiness for AI Pipelines at OFC 2026
At OFC 2026, the optical communications industry's premier event, the focus turned to whether co-packaged optics (CPO) is ready to support AI pipelines. Historically, IBM pioneered CPO 16 years ago with its Power 775 system, but modern AI clusters scaling toward 130,000 GPUs are pushing the limits of traditional copper and pluggable optical modules. The workshop gathered key players like Meta, Oracle, NVIDIA, Broadcom, Arista, Cisco, and AMD to discuss front-end silicon photonics yield, back-end cluster total cost of ownership (TCO), and liquid cooling. The event marked a shift from CPO being a technology showcase to volume production, signaling a potential reshaping of the 12.8T-to-51.2T network switching landscape.
Oracle emphasized the reliability benefits of CPO, particularly in its 130,000-GPU AI supercluster. The company advocates for socketed CPO approaches like PPAK to enable a multi-vendor ecosystem and backs Expanded Beam Technology to improve dust immunity and reduce mating force. Meta shared 50 million device-hours of CPO reliability data, showing significant improvements in mean time between failures (MTBF) over pluggable modules. Arista, however, argued that pluggable modules will not die, highlighting its 12.8T liquid-cooled XPO architecture, which offers significant density improvements.
Broadcom showcased its Tomahawk 6 CPO in production, announcing a shift from PAM4 modulation to NRZ encoding combined with WDM to avoid SNR penalties. Cisco offered a cautionary note, warning about yield and physical limits, while NVIDIA revealed commercial breakthroughs with micro-ring modulators (MRM) and TSMC's COUPE technology. AMD emphasized the need for new material processes to overcome modulator bottlenecks and the importance of close collaboration between OSATs and foundries.
The industry reached a consensus on the importance of TCO and RAS (reliability, availability, and serviceability) in AI clusters. There was agreement on the necessity of external laser sources (ELS) to improve reliability and reduce heat. However, strategic divergences emerged on the transition path at the 224G generation and the preference for soldered versus socketed CPO packages.