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

Abstract

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 schemes, 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 do not provide the changing an access tree. In this paper, we propose a Dynamic ABGS scheme that enables an access tree to be changed. Our ABGS is efficient in that re-issuing of the attribute certificate previously issued for each user is not necessary. Moreover, calculations depending on the number of attributes are calculated on the domain of a pairing. Therefore, the number of calculations in a pairing does not depend on the number of attributes associated with a signature. Finally, we discuss how our ABGS can be applied to an anonymous survey for collection of attribute statistics.