Attribute Based Group Signature with Revocation

In real life, one requires signatures to be from people who fulfill certain criteria, implying that they should possess specific attributes. For example, Alice might want a signature from an employee in Bobs company who is a member in the IT staff, a senior manager within the biometrics team or at least a junior manager in the cryptography team. In such a case an Attribute Based Group Signature scheme (ABGS) could be applied. Group signature schemes are those where each member of a group can sign on behalf of the others. An ABGS scheme is a type of group signature scheme, where the signing member has to have certain attributes. In [12], the authors introduced the first ABGS but it lacked the ability to revoke. In this paper, we introduce a new scheme that will enable us to remove a member from a group or remove some of his attributes, when needed.