Efficient and flexible attribute policy based key management
Mohamed Nabeel, Elisa Bertino · Annual Information Security Symposium · 2011
Attribute based systems enable fine-grained access control among a group of users each identified by a set of attributes. Broadcast services and secure collaborative applications, such as location based services, cloud storage services, multimedia streaming services and document dissemination, need such flexible attribute based systems for managing and distributing group keys. However, current group key management schemes are not well designed to manage group keys based on the attributes of the group members. Attribute based group membership policies allow to select any sub-group of users from a large group of users. In this poster, we propose novel key management schemes that allow users whose attributes satisfy a certain group membership policy to derive the group key. Our schemes efficiently support rekeying operations when the group changes due to joins or leaves of group members. During a rekey operation, the private information issued to existing members remains unaffected and only the public information is updated to change the group key. Our schemes are expressive and flexible; specifically they are able to support any monotonic group membership policy over a set of attributes. Further, our schemes are resistant to collusion attacks; group members are unable to pool their attributes in a meaningful way and derive the group key which they cannot derive individually.