An improvement on efficient anonymous auction protocols

In this paper, we propose an improvement on Chang et al.'s efficient anonymous auction protocols to overcome the security weakness in initiation phase of Chang et al.'s scheme. At first, we formally analyze the initiation phase of Chang et al.'s scheme on the basis of authentication tests to disclose the insecurity of the initiation phase. Then we give our attack to the initiation phase, which can make the following auction phase fail to run. Later, we propose our improvement on the initiation phase. Finally, we formally analyze our improved scheme with authentication tests, and prove the security of our improved scheme. Our improved scheme can preserve the merits of Chang et al.'s scheme and overcome the security weakness in initiation phase of Chang et al.'s scheme.