Abstract: In the existing SCF-PEKS scheme architecture, encrypting the server keyword public key depend on the user’s public key, which limit the service only to a certain user. The use of searchable encryption is greatly limited because users without the public key corresponding to the private key cannot search the data. The paper proposes a more efficient SCF-PEKS scheme which allows users to register for use based on composite-order bilinear group. This scheme allows multiple users to search the data without secure channels, users who need data search services finish keyword searches through registration. and the keyword public key encryption of the server no longer depends on the users public key. The scheme is proved to be secure against chosen keyword attack(IND-SCF-CKA) based on the decisional subgroup assumption in the standard model, which has a higher computing efficiency compared with current SCF-PEKS schemes.

Key words: searchable encryption, secure-channel free, composite-order bilinear group, registered users