US Patent 10489604 Searchable encryption processing system and searchable encryption processing method

A searchable encryption processing system includes a server including: a communication device to communicate with another device; a storage device configured to store as search target data, secret data obtained by concealing plaintext data, and a secret index obtained by concealing a plaintext index to classify the plaintext data; and an arithmetic device to execute a process including receiving, from a search client, a secret data query obtained by concealing a plaintext query, and a secret index query obtained by concealing a plaintext index, searching the storage device for a secret index matching the secret index query based on a predetermined searchable encryption technique, searching a secret data group classified by the matching secret index for secret data matching the secret data query, and returning the searched secret data to the search client.