Abstract: A computer system comprises a plurality of user computers interconnected through a public-switched telephone network and trunk lines, and also includes a plurality of Remote Data Processing Nodes (RDPNs) similarly connected to each other and to the user computers. A BBS station which is also coupled to the network receives test data from the user computers. Each user computer includes a test unit that includes a digital signal processor and an active control unit. The test unit has a dialing directory for connecting to various BBSs to test out the communication through a modem and the telephone network. Using the dialing directory, the test unit activates the modem to make a predetermined call through the telephone network to several of the RDPNs. The test unit collects survey, snapshot and real-time data packets in a predetermined data file which are communicated to the BBS station for debugging the system and determining the performance of the system.