Abstract: Ciphertext search can be used to protect user’s privacy when searching in plaintext. However, the index struction of most existing PEKS schemes are based on file keyword pairs, and each search needs to traverse all files, which will make the search efficiency of the scheme low. Moreover, the existing PEKS schemes only support static search operations, and the files in the cloud can not be updated dynamically, which will inevitably lead to waste of resources and inconvenience in using. In view of the existing problems, this paper proposes a more efficient dynamic public key searchable encryption scheme, which has certain performance advantages compared with other schemes, and proves that the scheme has the security under the adaptive dynamic keyword selection attack under the random oracle model, and can resist the keywords guessing attack.

Key words: cloud server, searchable encryption, public key, dynamic, keyword guessing attack