In order to be more effectively resist differential power analysis attacks, the improved fixed value masking algorithm is proposed for resource-constrained smart card based on fixed value masking and random masking. Firstly, a number of random numbers are selected and prestored in on-chip ROM for generating the corresponding byte-substitution table. It does not increase much power and hardware resources because the byte-substitution table is pregenerated. Finally, experiments in terms of the second-order differential power
analysis attacks have been carried out on the improved fixed masking. The experimental results show that the proposed AES
algorithm can be effectively resistant to the side-channel attacks with lower computing expenses and higher security.