line speed; connection speed
Technical computing term referring to the data transfer rate of a communication line or network connection.
With this line speed, downloading large files takes time.
I used a site that measures connection speed.
回線速度 refers to the speed of a particular line or circuit, whereas 通信速度 denotes the effective data transfer rate achieved over that line.
Compound of 回線 (line, circuit) and 速度 (speed). A straightforward technical term with no unusual etymology.