New Fiber Promises Lower Latency for AI

Hollow-core fiber inverts traditional fiber design by guiding light through an air-filled central channel instead of a solid glass core. This structure allows light to travel at approximately 99.97% of its speed in a vacuum, significantly faster than the 68% it achieves through solid silica glass. This air-guided transmission results in a latency reduction of about 30% compared to conventional optical fiber. In practical terms, where standard fiber introduces a delay of around 5 microseconds per kilometer, hollow-core fiber cuts that delay to approximately 3.3 to 3.5 microseconds. For AI systems, this latency reduction is most critical for inference workloads, which often require real-time responses for applications like autonomous driving or fraud detection. While AI model training can tolerate longer delays, inference directly impacts user experience and system responsiveness, where even millisecond delays are significant. Yangtze Optical Fibre and Cable (YOFC) has demonstrated a record-low attenuation for HCF at 0.05dB/km, outperforming traditional solid-core fibers. In June 2024, YOFC and China Mobile launched the world's first 800G hollow-core fiber transmission test network, achieving a throughput of 128Tb/s over a 20km link. The hollow-core fiber market includes established players like Corning, Prysmian Group, and OFS (Furukawa), who are also developing solutions. The global market for this technology is projected to grow, driven by demand from telecom operators, cloud providers, and for applications in quantum communication. Early adopters are already deploying this technology for latency-sensitive applications. euNetworks has used hollow-core fiber to connect two data centers in London, and Comcast has tested a 40-kilometer link in Philadelphia, confirming compatibility with existing infrastructure.