Key Technology Research On Side Channel Attack

Security has been widely and deeply studied in the area of networking and general purpose processors.Many of these works have produced essential security algorithms or applications such as DES,AES,SMS4,etc.Recently,security is also becoming an important issue in the embedded system domain.This is due to that many of the current embedded devices are used to manipulate sensitive information such as bank accout information.Further,there has been several security breaches reported in embedded system areas.For example,differential power analysis attacks have been shown to be able to reveal the secreat key stored in smartcard chips,electromagnetic attacks on smartcards,software flaw exploitations,etc.Such vulnerabilities have increased significantly with the proliferation of embedded systems.In this paper,First,we introduce statistical characteristics of power traces.we present statistical models for the individual points of power traces and for power traces as a whole.These models describe power traces in a way that power analysis attacks can be explained and analyzed relatively easily.Second,we introduce principle of differential power analysis,such as classical power analysis,power analysis of hamming weight or hanmming distance model.we also give some explames on block ciphers.In the explames,we give the detail of differential power analysis.Finally,we introduc higher-order Boolean masking schemes for block ciphers.The definitions of higher-order side channel attacks with the related security notions are formalised and certain security weaknesses in recently proposed masking schemes are put forward.The conditions upon which a substitution box in a block cipher can be perfectly masked by Boolean values at a masked S-box output.The consequences of this requirement are studied in two models,namely the Hamming weight and distance model.we also introduce the proof of conditions of perfect masking.