This paper proposes a hierarchical method for the formal hardware verification of Galois field architecture circuits. The reduced ordered functional decision diagram has been explored. The proposed method has been found to lead to significant gains in time and space, depending on the resources that are available. The theoretical claims that were made have been supported by experiments.

Scan chains are exploited to develop attacks on cryptographic hardware and steal intellectual properties from the chip. This paper proposes a secured strategy to test designs by inserting a certain number of inverters between randomly selected scan cells. The security of the scheme has been analyzed. Two detailed case studies of RC4 stream cipher and AES block cipher have been presented to show that the proposed strategy prevents existing scan-based attacks in the literature. The elegance of the scheme lies in its less hardware overhead.