Research And Improvement About Public Key Encryption With Keyword Search

With the frequent use of cloud storage, people would like to send the encrypted data to the cloud for storage. Searchable encryption ensures comprehensive search in the context that the server does not decrypt data. Thus, searchable encryption is a meaningful research fields. In this paper, all the proposed searchable encryption schemes are based on public key encryption.Based on the bilinear pairing technology, a designated tester Public-key Encryption with Keyword Search (dPEKS) which can resist off-line keyword guessing attacks is proposed. The scheme is proved to be indistinguishable of dPEKS against chosen plaintext attack (IND-dPEKS-CPA) in the random oracle model under 2-BDHI assumption and BDH assumption. Using CDH assumption, the scheme is proved to be trapdoor indistinguishable, which ensures the keyword guessing attacks resistance. During the whole dPEKS, the main amount of the computing is9Te, which makes it more efficient than the other schemes.Combined with lattice theories, a new lattice-based signature scheme for constant-sized message in the standard model is proposed. The scheme is proved to be existentially unforgeable against static chosen message attacks in the standard model under the small integer solution (SIS) assumption. In addition, using the TrapGen algorithm and SampleD algorithm on the ideal lattice, an ideal lattice-based PEKS is proposed. And the scheme is proved to be indistinguishable of PEKS against chosen plaintext attack (IND-PEKS-CPA) in the random oracle model under LWE assumption.