Circuit arrangement, data processing device comprising such circuit arrangement as well as method for identifying an attack on such circuit arrangement

A circuit arrangement, in particular an active shield, comprising

• at least one data signal generating device being designed for generating test data and expected test data,
• at least one group of data lines being designed for carrying data signals, in particular regular data and/or the test data, and
• at least one detector module being designed for identifying at least one attack on the circuit arrangement, the detector module comprising
• at least one transmitting device for transmitting the test data,
• at least one receiving device for receiving the test data having been transmitted from the transmitting device and
• at least one evaluation device for comparing the received test data with the expected test data and for ascertaining or determining any discrepancy between the received test data and the expected test data,
• characterized by
• at least one data line selection device for selecting part of the group of data lines to carry new or most recent test data having been generated by the data signal generating device.