Fuzzy matching: multi-authority attribute searchable encryption without central authority

Abstract

Attribute-based keyword search (ABKS) supports the access control on the search result based upon fuzzy identity over encrypted data, when the search operation is performed over outsourced encrypted data in cloud. However, almost ABKS schemes trust a single authority to monitor the attribute key for users. In practice, we usually have different entities responsible for monitoring different attribute keys to a user. Thus, it is not realistic to trust a single authority to monitor all attributes keys for ABKS scheme in practical situation. Although a large body of ABKS schemes have been proposed, few works have been done on multi-authority attribute searchable encryption. We propose a multi-authority attribute searchable encryption without central authority in this paper. Comparing previous ABKS schemes, we extend the single-authority ABKS scheme to multi-authority ABKS scheme and remove the central authority in multi-authority ABKS scheme. We analyze our scheme in terms of security and efficiency.