Chapter Three - Similarity of Private Keyword Search over Encrypted Document Collection

Due to its cost-efficiency, flexibility, and offload of administrative overhead, cloud computing has become a viable option for organizations to outsource their data and services. To protect data confidentiality, sensitive data need to be encrypted before outsourced to a cloud. In such case, the task of query processing over encrypted data becomes not trivial. A typical example is a private keyword search where a collection of encrypted documents is stored on a cloud and a user retrieves a subset of documents from the collection containing a given set of keywords. In the process, the set of keywords and the original documents are never disclosed to the cloud. To solve this problem, many schemes have been proposed to allow users to securely search over encrypted document collection through exact and similarity keyword matching. In this chapter, we provided a comprehensive literature survey on the existing schemes of private keyword search.