In contrast to a dial-up line, a leased line is a permanently switched connection between two stations that is available at all times. Leased lines can be rented from network operators.
In the past, leased lines were pure point-to-point connections; today, leased lines can be subjected to dynamic bandwidth management between several subscribers by means of routers. If bandwidth management affects different locations, the cost of leased lines increases considerably.
Leased lines are not scalable, and the bandwidths offered show large jumps in transmission speeds. They are offered as E1 lines with 2.1 Mbit/s, as E3 lines with 34 Mbit/s, DS3 with 45 Mbit/s, STM1 with 155 Mbit/s and STM4 with 622 Mbit/s.