Abstract: The polling features of a resident hybrid fiber/coax (HFC) network platform are used to poll between a link a hybrid digital terminal (HDT) and a network interface unit (NIU). In the absence of a polling response from the NIU to a polling query from the HDT, the polling is regarded as unsuccessful. Hence, every polling query with no response from the NIU means the polling is unsuccessful and counted as a failed polling. The unsuccessful polling will be the result of an outage causing fault such as a physical break anywhere between the NIU and the HDT. Using an exception report format, only the unsuccessful pollings are reported and the counted. To calculate the unavailability of the link during any period of time, the number of counts within the period is acquired and used in the measurement process. The result is a statistical measure of the link unavailability during a specified time period, which may be one day, one year, or any suitable unit of time.