Optical modules —including SFP, QSFP, and CWDM series —serve as the core components enabling this high-speed, high-bandwidth, and long-distance connectivity. Without them, even the most powerful GPU clusters would be bottlenecked by network limitations. High-Speed Data. Various versions of calculations regarding the ratio of optical modules to GPUs circulate in the market. GPUs such as the A100, H100, and upcoming GH100 require high-speed optical interconnects to link thousands of GPU nodes, enabling large-scale AI model training and inference.