A network control and test system for application to data communications networks. In a first mode of operation, the system learns the network configuration automatically and builds a table describing the network configuration. In a second mode of operation, the system automatically monitors the status of the network and each of its component units, periodically polling the network for changes of status and updating the information in the network configuration table to reflect such changes. In a third mode of operation, selective sites in the network may be tested under control of the system at previously selected and entered times of day, at which times previously chosen tests are performed without the need for operator intervention. In a fourth mode, an operator can manually command the system to perform certain tests and control functions. A central site in the network includes the primary components of the system and each remote site includes a remote test module which operates under the control of and in cooperation with the central site equipment. The central site equipment includes a three-tiered, partially distributed data processing system having a semi-autonomous data processing system at each tier. Each of the tiers has predetermined functions and responsibilities.