# Symmetric private information retrieval (Single-server) Symmetric private information retrieval is a stronger version of [[Single-Server Private Information Retrieval]] that in addition to protecting the querier's privacy, also protects the data privacy. The multi-server, information-theoretic version was introduced by [[GIKM00 - Protecting Data Privacy in Private Information Retrieval Scheme|GIKM00]], but follow-up works showed how to construct computationally secure versions based on assumptions. ## Definition ### Variations ## Other results - Single-server SPIR is equivalent to $1$-out-of-$n$ [[Oblivious transfer|OT]] with an additional efficiency requirement -