A Dynamic Attribute-Based Group Signature Scheme and its Application in an Anonymous Survey for the Collection of Attribute Statistics

Recently, cryptographic schemes based on the user's attributes have been proposed. An Attribute-Based Group Signature (ABGS) scheme is a kind of group signature scheme, where a user with a set of attributes can prove anonymously whether she has these attributes or not. An access tree is applied to express the relationships among some attributes. However, previous schemes did not provide a way to change an access tree. In this paper, we propose a dynamic ABGS scheme that can change an access tree. Our ABGS is efficient in that re-issuing of the attribute certificate previously issued for each user is not necessary. The number of calculations in a pairing does not depend on the number of attributes in both signing and verifying. Finally, we discuss how our ABGS can be applied to an anonymous survey for collection of attribute statistics