noun
leased line; private circuit; private line
A dedicated telecommunications line rented from a carrier for exclusive use, often for corporate networks. Technical computing term.
本社と支社の間は私設回線で結ばれている。
The head office and the branch office are connected by a leased line.
私設回線はセキュリティ面で有利だ。
A private line is advantageous in terms of security.
専用線 is a broader term for any dedicated line, while 私設回線 specifically refers to a leased line from a carrier.
Compound of 私設 (privately established) and 回線 (circuit/line).