Date Added: Jun 2009
This paper takes a closer look at the security of outsourced databases (aka Database-as-the-Service or DAS), a topic of emerging importance. DAS allows users to store sensitive data on a remote, untrusted server and retrieve desired parts of it on request. At first it focus on basic, exact-match query functionality, and then extend treatment to prefix-matching and, to a more limited extent, range queries as well. It proposes several searchable encryption schemes that are not only practical enough for use in DAS in terms of query-processing efficiency but also provably-provide privacy and authenticity of data under new definitions of security that it introduces.