Performance monitoring system for T1 telephone lines

摘要

A system for monitoring the performance of T1 digital transmission lines by incorporating a common unit interconnected to a plurality of network interface units as well as to a spare transmission line leading to a central office. The common unit is configured to interrogate any or all of the network interface units in order to obtain status information such transmission error rates, and to report such status information via the spare transmission line to the central office. By dedicating a common unit to oversee error detection and/or status reporting, communication between the central office and customer premises equipment need no longer be disrupted while transmission performance is being monitored.