line capacity; circuit capacity
Technical term in computing and telecommunications referring to the maximum data transmission rate or bandwidth of a communication line or circuit.
With this line capacity, transferring large amounts of data is difficult.
We introduced new equipment to increase the circuit capacity.
帯域幅 (bandwidth) is a more common term for the width of a frequency band, while 回線容量 specifically refers to the capacity of a communication line or circuit.
通信速度 (communication speed) is a broader term for data transfer speed, whereas 回線容量 emphasizes the maximum capacity of the line itself.
Compound of 回線 (circuit, line) and 容量 (capacity). The exact historical derivation is uncertain, but the term is a straightforward technical compound.