A research team involving China Information and Communication Technologies (CICT), Peng Cheng Laboratory and FiberHome Fujikura Fiber Optic Technology Co., Ltd. reported 3.2 petabits per second of total, bidirectional, real-time transmission over 10.3 kilometers of experimental 24-core fiber. That is a research demonstration, not a household broadband service or a one-way speed of 3.2 Pb/s.
What the 3.2-Pb/s test measured
The reported rate is the combined capacity of traffic moving in both directions across one fiber. The experiment used a 24-core optical fiber, which carries signals through multiple cores within the same fiber, over a 10.3-kilometer link.
That scope matters: a total bidirectional rate does not tell you the rate available in just one direction. The result describes a particular fiber and test distance, rather than a speed consumers can expect from an internet connection.
How the reported fiber system carried data
The system combined S, C and L wavelength bands with wavelength-division and space-division multiplexing. Wavelength-division multiplexing carries separate channels at different wavelengths; space-division multiplexing uses separate paths, including the fiber’s cores, to carry data.
The Paper’s account also reports commercial coherent optical modules, higher-order probabilistic shaping and a core arrangement intended to reduce crosstalk, or signal interference between cores. Commercial modules describe components used in the experiment; they do not make the experimental fiber a commercial service.
A 1,808-kilometer test measured a different reach
The National Institute of Information and Communications Technology (NICT) reported a separate 2025 experiment transmitting 1.02 Pb/s over 1,808 kilometers using coupled 19-core fiber. The Chinese test reported a higher capacity over a much shorter distance, with a different fiber configuration. Those figures describe distinct engineering tests, not a like-for-like ranking.
| Experiment | Reported capacity | Distance | Fiber configuration and focus |
| CICT collaboration | 3.2 Pb/s, total bidirectional real-time transmission | 10.3 km | Experimental 24-core fiber; short-link capacity |
| NICT, 2025 | 1.02 Pb/s | 1,808 km | Coupled 19-core fiber; long-distance transmission |
The 295-EB calculation takes more than eight days
If 295 exabytes is used as an estimate of global storage in 2007, the arithmetic at 3.2 Pb/s is 737,500 seconds, or 8 days, 12 hours, 51 minutes and 40 seconds. In decimal units, 3.2 Pb/s equals 400 terabytes per second, and 295 EB equals 295 million TB.
That is an idealized calculation, not a measured transfer. It also treats the experiment’s entire aggregate bidirectional capacity as if it were available for a one-way transfer, an assumption the reported figure does not establish.
Possible network uses are not a household rollout
The Paper identifies links between large computing centers, backbone networks and future 6G networks as possible uses. The reported result remains a 10.3-kilometer research experiment; it does not describe a home broadband service or a rollout schedule.
