Abstract: Attack process of side channel attacks can be regarded as mutual information gambling process. Both sides of the game were cryptographic equipment designers(defense party) and the attacker. The game goal of defenders is for- mulcted by the defense strategy to reduce local and global risk which caused by the side channels leakage; to attack side, the game target and to the contrary. From make safety strategy,reduce safety risk angle,mutual infom}ation game theory is introduced in the decision-making process of the cryptographic chips designers(defense party) and the attacker,to in- vestigate the attack and design tactics choice to security risks, and combined with the quantitative methods of the mutual information, give the optimization tactics selection method of the both sides of attack and design on Nash equilibrium conditions,give the mutual information benefits of the both sides of attack and design on Nash equilibrium.

Key words: Mutual information game, Sidcchanncl attack, Risk, Risk evaluation