With the upgrade of the information system confrontation

the cyberspace has developed to a complicated network electricity environment

composed of kinds of interconnected information platforms and control networks. Its security threats has been more complicated. As the security base of the cyberspace

the fault disturbance to the implementation of the cipher

caused by the environment and the malicious attacker

can not be avoided

so the security problem of the cipher will be induced. In this paper

based on the voltage glitch fault injection

the fault generation and the security disturbance mechanism of the block cipher chip

is analyzed. The fluctuant model

used for characterizing the fault propagation probability of the cipher chip

is constructed. Applying the indistinguishable theory

and the statistical distribution of the propagation probability to the active bytes

the metric model of the actual physical security for the block cipher chip

is proposed. It is experimented that

the relevance

between the actual fault propagation probability and the distinguish advantage

can be reflected by the model

so the security of the block cipher

in the scene of the fault attack

can be analyzed objectively.