Multi-keyword ranked searchable public-key encryption
Chengyu Hu, Bo Yang, Pengtao Liu · International Journal of Grid and Utility Computing · 2015
Most related works on Public-Key Encryption with Keyword Search scheme (also called Searchable Public-key Encryption) focus on single keyword search. Some works supporting multi-keyword search cannot provide search result ranking. In this paper, we study the problem of multi-keyword ranked search over encrypted data in public-key model. We propose the definition of Multi-Keyword Ranked Searchable Public-key Encryption/Public-Key Encryption with Multi-Keyword Ranked Search. In the definition, we allow the receiver to query any set of keywords. As the query result, the receiver can get the number of queried keywords appearing in the encrypted data, which can be used to evaluate the similarity ranking of the data keywords to the search query in 'as many matches as possible' principle. We put forward a generic construction for public-key encryption with multi-keyword ranked search scheme with sub-linear ciphertext based on any anonymous hierarchical identity-based encryption scheme and provide the security analysis. At last, we present a concrete scheme with sub-linear ciphertext.