An anti-trojans design approach based on activation probability analysis

Hardware Trojan, realized by malicious modification of design characteristics, has emerged as a major security concern. The recently proposed Trojan detection methods are mainly classified into two categories: side-channel signal analysis and logic testing. Due to the stealthy nature of Trojan circuits, it's difficult to activate Trojans to perform logic testing. In this paper, an activation probability-based approach is proposed. A probability obfuscation scan chain (POSC) is presented aiming at increasing the difficulty of Trojan insertion and increasing the activation probability of the Trojan circuits. It proves to be very effective in detecting the presence of a Trojan in a circuit. Experimental results on ISCAS benchmark circuits show that this approach can effectively increase Trojan activation probability and make the detection of the Trojan more easily.