Key dependent operation and algorithm specific complexity of statistical side channel attacks

This paper analyzes the design of cryptographic algorithm and the effect of their vulnerability towards statistical side channel attacks. On the example of the DPA (differential power attack) attack by Kocher the complexity of the statistical side channel attacks and their dependency on algorithmic parameters is shown. In particular key dependent operation are considered and their effect is illustrated on the example of the block cipher algorithm AES and Twofish. It is shown that the careful selection or design of algorithms can increase the security of implementations of algorithms in addition to and independent from conventional DPA attack counter-measures.