Abstract: A system tests a repeating installation having transmitter-receivers (3, 4) and a line controller (2). The system includes the repeating installation to be tested, a first tester (10), a second tester (11), an input unit (12) for entering a first virtual network into the first tester (10), an input unit (13) for entering a second virtual network into the second tester (11), and a line control table which is provided for the transmitter-receiver (3) and into which the destination transmitter-receiver (4) is written according to address information added to the data input to the transmitter-receiver (4). Test data transmitted from the first tester to the virtual network of the second tester is received by the second tester, and the received test data is examined. This greatly reduces facility costs and installation space and realizes performance evaluation of a repeating installation under a large-scale network environment.