An apparatus includes an integrated circuit and a plurality of conducting wires disposed on the integrated circuit. The integrated circuit includes: (i) a signal generation circuit, which is configured to generate random signal and selection signal based on random or pseudo-random numbers, (ii) a transmitting circuit configured to select at least one from among the plurality of conducting wires based on the selection signal and to output the random signal through the at least one conducting wire, and (iii) a receiving circuit configured to detect an invasive attack on the integrated circuit based on signal received through the at least one conducting wire.