Loop plant modeling: Optimal operating policies for serving areas using connect-through administration

Connect-Through administration is the policy of leaving the pair from a customer's premises to the central office intact when the customer disconnects from the network. A pair in this idle state is called a connect-through (CT) pair. In a serving area (the geographical entity in which all customers are served through an interface connecting the feeder and distribution parts of the network), growth may lead to the condition where no spares remain in the interface. It then becomes necessary to consider breaking CT pairs or providing additional spare pairs (relief). In this paper, two related operating decisions are examined. First, in order to determine under what conditions relief is more economical than breaking CTs, models are developed to compare the expected operating cost due to breaking CTs with relief costs. Second, when breaking a CT is the preferred procedure, it is shown that the optimal policy is to break the CT with the smallest instantaneous reuse probability, given by the hazard function of the premise vacancy time.