Biblio

Given two strings: pattern p of length m and text t of length n. The string matching problem is to find all (or some) occurrences of the pattern p in the text t. We introduce a new simple data structure, called index arrays, and design fast privacy-preserving matching algorithm for string matching. The motivation behind introducing index arrays is determined by the need for pattern matching on distributed cloud-based datasets with semi-trusted cloud providers. It is intended to use encrypted index arrays both to improve performance and protect confidentiality and privacy of user data.

With the growth of cloud computing, database outsourcing has attracted much interests. Due to the serious privacy threats in cloud computing, databases needs to be encrypted before being outsourced to the cloud. Therefore, various Top-k query processing algorithms have been studied for encrypted databases. However, existing algorithms are either insecure or inefficient. Therefore, in this paper we propose an efficient and secure Top-k query processing algorithm. Our algorithm guarantees the confidentiality of both the data and a user query while hiding data access patterns. Our algorithm also enables the query issuer not to participate in the query processing. To achieve a high level of query processing efficiency, we use new secure protocols using Yao's garbled circuit and a data packing technique. A performance analysis shows that the proposed algorithm outperforms the existing works in terms of query processing costs.