Loop Plant Modeling: Optimal Operating Policies for Serving Areas Using Connect-Through Administration

Connect-Through administration is the policy of leaving the loop from a customer's premises to the central office intact when the customer disconnects from the network. This idle, but reserved, pair is called a connect-through (CT) pair. The savings from avoiding the disconnection operation and from having the pair available for reuse when (and if) a new customer moves into the same location may be counterbalanced by the fact that with fewer spare pairs available for new customers, costly loop network reconfigurations will be required more often. CONNECT-THROUGH ADMINISTRATION 911 Recent emphasis has been placed on understanding the effects of CT administration because of the decision to establish PhoneCenters in the Bell System. In a PhoneCenter environment, a customer may obtain the telephone in a PhoneCenter store. In many cases the customer can also connect the telephone to the network through jacks previously installed in his residence. This eliminates the need for any work inside the residence by the installer. If, in addition, a CT pair to this residence is available, no installer work of any kind is required. The savings from having a CT pair available for reuse are then much greater since the installer trip can be eliminated. Still, the trade-off between reuse savings and loop network reconfiguration costs must be evaluated to determine an optimal policy. A serving area is a geographical entity (200 to 600 living units) served by feeder pairs terminated in a single interface (see Long,1 this issue).