RaySync is a very large file transfer acceleration service developed by Shenzhen Yunyu Technology. It is designed to provide big data transfer services for large and medium-sized companies such as Huawei. RaySync's TCP-based transmission is reliable. You only need to install the RaySync cloud server and local client at the same time to achieve high-speed transmission services. I tested it with my own cheap American VPS host ChangeIP and found that the speed-up effect is very obvious.