Demarcation Point

The demarcation point is the physical location at which the telephone carrier’s infrastructure ends, and the customer’s infrastructure (CPE) begins, in order to determine whether maintenance of wiring and equipment is the responsibility of the telephone company or the customer.

Prior to deregulation in 1976, by the U.S. Federal Communications Commission (FCC), telephone companied owned and maintained all wiring and equipment on the customer’s premises. The Bell System (AT&T) required all CPE to be isolated from the PSTN by protective couplers, installed and maintained by they company, but paid for, monthly, by the customer.

The FCC order abolished the requirement for the protective coupler and allowed customers to directly connect their own equipment to the telephone network. It also established the use of registered jacks as demarcation points on the customers’ premises.

The demarcation point has changed since its inception in the 1970s. Today, the it is often network interface device (NID) or intelligent network interface device (INID) at the main point of entry (MPOE), either inside the building or in a weather-resistant box on the building exterior.

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Created 2023-03-09 05:57 by Stephen B (Revised 2023-03-11 09:49)

Keywords: Demarc

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