Optimal Hamming Distance Model for Crypto Cores against Side Channel Threats

Microelectronic crypto devices contain intellectual property like secret data to be protected against side channel attack. Scan chain based attacks come under the category of side channel attack where the hackers attack a scan path through observing and comparing the relationship between intermediate hamming distances values for different test vector patterns. Hence our novel hamming model should overcome the scan based attack and should not give any correlation relationship in hamming distance by providing the similar intermediate values for all test vector patterns which are obtained through an optimal way of inserting Optimal Scan Flip Flop (OSFF) randomly to the scan path chain. Implementation of our proposed integrated circuits is written in Verilog and synthesised with XILINX Spartan III FPGA. The report is compared with Robust Scan Flip Flop (RFSS) hamming model to estimate the overhead of component minimized in OSFF.