Private set intersection

In this scenario, neither party reveals anything to the counterparty except for the elements in the intersection.

[2] For the comparison of data sets by cryptographic hashes on a small or predictable domain, precautions should be taken to prevent dictionary attacks.

In the traditional PSI category, the data owners interact directly with each other and need to have a copy of their set at the time of the computation, e.g.,.

[7] Those that support repeated delegation allow the data owners to upload their (encrypted) data to the server only once, and then re-use it many times for each computation carried out but the server, e.g.,[8] Recently, researchers have proposed a variant of PSI protocol (in both traditional and delegated categories) that support data update, e.g., .

[9][10] This type of PSI protocol lets data owners insert/delete set elements into/from their data with low overheads and in a privacy-preserving manner.