The term may refer to a connection between a carrier's facilities and the equipment belonging to its customer, or to a connection between two (or more) carriers.
该术语可以是指在某个运营商的设施和属于它的客户的设备之间的一个连接（设备间互联），也可以是两个（或更多）运营商之间的连接（网间互联）。