Dynamic Searchable Encryption in Very-Large Databases: Data Structures and Implementation

Abstract

We design and implement dynamic symmetric searchable encryption schemes that efficiently and privately search server-held encrypted databases with tens of billions of record-keyword pairs. Our basic theoretical construction supports single-keyword searches and offers asymptotically optimal server index size, fully parallel searching, and minimal leakage. Our implementation effort brought to the fore several factors ignored by earlier coarse-grained theoretical performance analyses, including lowlevel space utilization, I/O parallelism and goodput. We accordingly introduce several optimizations to our theoretically optimal construction that model the prototype's characteristics designed to overcome these factors. All of our schemes and optimizations are proven secure and the information leaked to the untrusted server is precisely quantified. We evaluate the performance of our prototype using two very large datasets: a synthesized census database with 100 million records and hundreds of keywords per record and a multi-million webpage collection that includes Wikipedia as a subset. Moreover, we report on an implementation that uses the dynamic SSE schemes developed here as the basis for supporting recent SSE advances, including complex search queries (e.g., Boolean queries) and richer operational settings (e.g., query delegation), in the above terabyte-scale databases.

Self-Enforcing Access Control for Encrypted RDF

“…Extensive work has been done in basic SSE, which caters for a single keyword [6]. Recent improvements have been proposed to handle conjunctive search over multiple keywords [5], and to optimise the resolution to cater for large scale data in the presence of updates [4,20,30]. However, all of these works focus on keyword-based retrieval, whereas structured querying (such as SPARQL) over encrypted RDF datasets would require (at least) an unrestricted set of triple query patterns.…”

Searchable Data Vault: Encrypted Queries in Secure Distributed Cloud Storage

“…We note that this is similar to a single server SSE scheme, for example, as proposed in [19,23,26]. The only difference is the process of division/combination of documents and distribution over multiple storage servers within each algorithm.…”

“…A scheme achieving sublinear search time using inverted index was also proposed. Most of the subsequent SSE schemes, such as schemes in [5,[20][21][22][23][24][25][26][27] adopted or extended the model proposed by Curtmola et al [19]. All these schemes are based on a single server.…”

Implementation of E-Health Cloud System Using Timing Enabled Proxy Re-encryption function (Re-dtPECK)

“…Cash et al [9] developed Searchable Symmetric Encryption (SSE) which permits a user to store data at an untrusted server and shortly search the information for the respective records which coincides with the given keyword simultaneously maintaining privacy. The issue aroused in this paper as it supports one word searches and provides optimal index server size.…”