China Achieves 51 Tbps Data Transmission Over 206.5 km Hollow-Core Fiber

A new world record has been established with 51.3 terabits per second (Tbps) transmitted across 206.5 kilometers of hollow-core fiber (HCF) without using any signal repeaters. This achievement, by China Telecom, fiber manufacturer YOFC, and Dekoli, represents enough bandwidth to simultaneously stream approximately 6,400 4K videos over a single cable spanning a distance comparable to that between London and Newcastle.

The trial utilized the longest commercial cross-border hollow-core fiber link to date, marking a significant transition from laboratory experimentation to practical deployment. Unlike traditional fiber optic cables that transmit light through a solid glass core, hollow-core fiber replaces the glass with air, allowing photons to travel faster and experience less signal degradation over long distances.

According to the results of the YOFC field trial, this technology reduces latency by about 31% compared to conventional fiber optics. Such a reduction is particularly valuable in sectors like financial trading, cloud computing, and artificial intelligence, where every millisecond impacts performance and cost.

The 206.5 km span was amplified solely using standard Erbium-Doped Fiber Amplifiers (EDFA) positioned at each endpoint, with no intermediate stations involved. This setup implies fewer active components for network operators to maintain, leading to lower operational expenses and reduced failure points along extensive backbone routes.

The Global Competition in Hollow-Core Fiber Deployment

China's progress in hollow-core fiber technology is part of a broader global effort. Microsoft, for instance, has already implemented 1,280 km of HCF within its Azure infrastructure without any reported field failures. The company aims to expand this network to 15,000 km by the end of 2026 through partnerships with Corning and Heraeus, which handle production in the United States and Europe respectively.

This expansion is expected to enhance data center interconnections, particularly benefiting cloud hubs in the UK and US by providing lower-latency backbone routes within the coming years. The China Telecom trial, with its achievement of 1.2 Tbps per wavelength across 43 channels without repeaters, intensifies competition and may accelerate procurement decisions industry-wide.

High-frequency trading routes connecting exchanges and colocation centers, such as the Shenzhen-to-Hong Kong corridor, are identified as the most immediate commercial applications for this technology.

Challenges Remaining for Hollow-Core Fiber Adoption

Despite its advantages, hollow-core fiber is not yet a straightforward replacement. The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) is still reviewing the technical standards for HCF, which means carriers cannot yet purchase standardized components. Additionally, splicing hollow-core fiber requires specialized tools and trained personnel.

While manufacturing capacity is increasing, lead times remain lengthy. For network operators in the US and UK, the technology's viability at scale is now established; however, the primary limitation lies in the supply chain rather than the underlying physics.