Progress and prospect of transcontinental high-speed data transmission at the Square Kilometre Array Regional Center in China

The Square Kilometre Array (SKA) is the largest radio telescope, and the data generated from its observations are first transmitted from Australia and South Africa to the scientific data processing center 100 km away, and then distributed to various SKA Regional Centres (SRC) with a distance of tens of thousands of kilometers through a high-speed network. In the SKA Phase 1 (SKA1) stage, 710 PB of data needs to be distributed to each SRC through a network of at least 100 Gbps each year. Such high network bandwidth and data scale bring great challenges to data transmission and distribution. This study analyzes a variety of network protocols, such as TCP/UDP/HTTP, and uses different software in the field of radio astronomy for testing and research. Then, the optimal transmission scheme parameters under the current infrastructure of a 10 Gbps network are obtained. In this study, the factors affecting high-speed transmission are discussed, and the corresponding performance optimization strategies are given. This study provides the technical foundation for China's network construction and layout before the official observation of the first stage of SKA and the technology accumulation of global network operations of the SRC in the future. The technical details and methods described in this study are essential for scientific applications that rely on large data cross-international nodes.