minimum point of entry). This then becomes the responsibility of the end user to extend their service to the CPE location within a facility to provide connectivity for service, requiring a service interface extension, or otherwise called a demarc extension. United Kingdom In the United Kingdom, the demarcation point occurs on the LJU master socket, whose wiring is partly owned by the customer, partly owned by the phone company. Other secondary sockets are the customer's property. Newer NTE-5 master phone sockets have a removable front panel: the front panel and its wiring is the customer's, while the rear wiring is Openreach's. The removable panel allows separation of these two parts and independent maintenance, and access to a test socket to determine whether line faults are in the customer's wiring or Openreach's (formerly BT's) external network. See also 66 block 110 block Carterfone Customer-premises equipment Hush-A-Phone Corp. v. United States Interconnection Main distribution frame Network interface device On-premises wiring Point of appearance Service termination point References External links Demarc extension terminology Part 68 Telecommunications Act of 1996 Local loop Telephony equipment