Abstract: Differential power attack is one of the most effective methods to reveal the key of cryptographic devices. Therefore, an energy trace classification method based on energy model is proposed to locate the significant points that have strong correlation with the key. Two energy models (hamming distance and hamming weight) are used, and a few sampling points near the significant point are intercepted to form the significant interval. The SoC chip with 128-bit AES algorithm under different keys is attacked. The actual test results show that the length of the optimal characteristic interval obtained by hamming distance energy model is short. Finally, the characteristic point location method based on hamming distance energy model has low sample calculation and reduces a large amount of samples.

Key words: differential power attack;system on chip;energy model, significant point;characteristic interval;energy trace