Abstract: To deal with the existing problems of multi-user searchable encryption schemes in the cloud computing,we firstly proposed a basic multi-user searchable encryption scheme,and then extended this basic scheme to a multi-user searchable encryption scheme with anonymous hierarchical permission management.Compared with existing schemes,our scheme not only achieves privacy preserving in both of the searching content and users’ identities,but also allows the data owner to directly control the dynamic updating of query permission.Additionally,our scheme realizes the hie-rarchical users’ query permission management by adopting a specific query key generation rule.The security of our scheme was illustrated by security analysis.Performance evaluation and experimental result show that our scheme is practical and feasible.

Key words: Encrypted keyword search,Anonymous query,Multi-user searchable encryption,Hierarchical permission management