Unfortunately, no file transfer protocol built atop ssh (scp, sftp, etc.) can have high throughput rates over high-latency links because ssh has a small, fixed

Unfortunately, no file transfer protocol built atop ssh (scp, sftp, etc.) can have high throughput rates over high-latency links because ssh has a small, fixed TCP window size. There are high performance forks available like HPN-SSH but they are rarely used in practice. Currently, the highest performing remote file transfer that I’m aware of for most situations is HTTPS.