A fixed telephone line (previously called main telephone line in operation) is an active* line connecting the subscriber's terminal equipment to the public switched telephone network (PSTN) and which has a dedicated port in the telephone exchange equipment. This term is synonymous with the terms main station or Direct Exchange Line (DEL) that are commonly used in telecommunication documents. It may not be the same as an access line or a subscriber. This should include the active number of analog fixed telephone lines (112a), ISDN channels (28c), fixed wireless (WLL), public payphones (1112) and VoIP subscriptions (112IP). If not included, specify in a note. *Active lines are those that have registered an activity in the past three months.