Signature-Masked Authentication Using the Bilinear Pairings

Many cryptographic schemes based on the bilinear pairings, namely the Weil pairing and the Tate pairing, were proposed recently. In this paper, we show that from these pairing-based cryptographic primitives, signature-masked authentication schemes can be developed. In such a scheme, a legitimate user obtains a signature from a Certificate Authority, and in order to get services from a service provider, he convinces the service provider that he has the signature without transmitting the original signature to the provider. Then no adversary (including the provider), who eavesdrops over the channel between the user and the service provider, can deduce the signature from what he saw over the channel and impersonate the legitimate user to get service from the provider.