Cryptogram-based safe full-text indexing and retrieval system

Abstract

The invention discloses a cryptogram-based safe full-text indexing and retrieval system. In the system, a cryptogram index library comprises a cryptogram entry reverse index and an internal document object set; a cryptogram document library is responsible for storing and managing an encrypted XML document; a word segmentation encryption server carries out Chinese word segmentation on a plaintext document and encrypts the plaintext document item by item; a cryptogram full-text indexing server standardizes an original plaintext document into an XML document, encrypts and stores the XML document in the cryptogram document library, creates a corresponding internal document object in the cryptogram index library by combining document metamessage, and creates a cryptogram reverse index for the XML document through the cryptogram entry; and a cryptogram full-text retrieval server retrieves the cryptogram index library to obtain the internal document object set through user authority information and the cryptogram entry, obtains a corresponding encrypted XML document result set from the cryptogram document library according to a pointer, decrypts the corresponding encrypted XML document result set, and returns the decrypted corresponding encrypted XML document result set to a user. The Chinese word segmentation method, the safe and high-efficiency indexing structure and the retrieval mechanism of the invention based on the special requirements of cryptogram full-text indexing can realize the cryptogram full-text indexing integrated with an access control strategy. The cryptogram-based safe full-text indexing and retrieval system has the advantages of a safe and high-efficiency indexing process, no decrypted docuterms in the indexing process, a high recall ratio and a high precision ratio in a cryptogram environment, and the like.

Description

technical field

[0001] The invention relates to the technical fields of information retrieval and information security, in particular to a secure full-text index and retrieval system based on ciphertext. Background technique

[0002] The information retrieval technology of full-text retrieval first appeared in the 1950s. In 1959, the Legal Information Retrieval System established by the Health Law Center of the University of Pittsburgh in the United States was the first full-text retrieval system in the world. In 1973, Lexis, a large-scale full-text database mainly including laws, news, business economics, and government publications, was put into use by Meade Corporation of the United States for public inquiries, marking the birth of the field of full-text retrieval. Since the 1980s, English full-text retrieval has developed rapidly and perfected, and now it has become the mainstream of foreign text-based information retrieval.

[0003] In China, the full-text retrieval t...

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