关键词: 国际数据加密算法（IDEA）, 差分功耗攻击, 汉明距离, 功耗模型, 旁路攻击

Abstract: By analyzing the features of International Data Encryption Algorithm（IDEA）, this paper presents a Differential Power Analysis（DPA） attacking method on IDEA code system, which is based on Hamming distance. The method is one particularly powerful type of Side Channel Attacks（SCA）. All its theories are based upon the physical characters, power consumption models and data dependent power consumption of CMOS logic gates which form the Integrated Circuits（ICs）. The paper introduces the design and realization of DPA attacks of IDEA. Correct secret key of encryption algorithm is cracked successfully with experiments. It comes gradually and closely into ultimate target of the attack. The result indicates that IDEA encrypted system without some extra protective measures can’t resist the attacks of DPA, because of the leakages from the physical signals and the difference of power consumption while processing the different data of ICs. The results can provide the researchers a useful reference for the safety design.

Key words: International Data Encryption Algorithm（IDEA）, differential power analysis attacks, Hamming distance, power consumption model, side channel attacks