Multi-user searchable encryption system with index validation and tracing and method thereof

PURPOSE: A search available password system at multilateral environment capable of the index verification and tracking and a method thereof are provided to verify the index which is produced by each user, in the data based in which a plurality of user uses at the same time, and are provided to track the user who produced the index. CONSTITUTION: A key distribution center (200) distributes a personal secret key to a user (S102). The key distribution center tracks the information about a user who produced the index (S112). A user terminal device (204) produces the index for searching the database by using the personal secret key (S104). A database (DB) server (202) verifies the index which is produced in the user terminal. The DB server searches and provides the data which corresponds to the verified index (S110). [Reference numerals] (200) Key distribution center; (202) Database (DB) server; (204) User terminal device; (AA) System parameter generation; (BB) Public key distribution; (S104) Index generation; (S106) Index verification; (S108) Trap door generation; (S110) Searching; (S112) Tracing