Cryptograph index structure based on blocking organization and management method thereof

Abstract

The invention discloses a cryptograph index structure based on a blocking organization and a management method thereof. Aiming at a blocking cryptograph index structure, an index establishing mode based on combination is firstly adopted to establish a plain text index when the index is established, and then the plain text index is blocked and encrypted in a unitive way. A maintenance mechanism based on a cryptograph index is divided into the addition, the deletion and the modification of a document in the index. The addition of the document is mainly divided into two conditions of batch addition and littleness addition; in the batch addition, a temporary index is established on a disc; and in the littleness addition, an internal memory index is established. In the deletion of the document,a deletion mark is firstly made on the document to be deleted, and the document is deleted in a unitive way until a proper opportunity. In the modification of the index, an original document is firstly deleted, and then a novel document is anew added. In a key management strategy, stratification management is carried out on an index encryption key, and the update of the key is realized by a timestamp mechanism. In an access control strategy based on the index, access control information is integrated into the index, and the access control of document level granularity is realized.

Description

Technical field [0001] The invention relates to the technical field of information retrieval and information security, in particular to a ciphertext index structure based on block organization and a management method thereof. Background technique [0002] Driven by the global informatization tide, information expands uncontrollably. It has become essential to provide efficient retrieval capabilities for the management of large-scale digital information. At the same time, a large number of data collections are maintained in such as enterprise data information centers, and they are stored in a secret form to limit unauthorized access by unauthorized users. , For example, sensitive government confidential documents, company trade secrets, etc. [0003] The key issue is how to protect these encrypted data document sets, and to be able to establish a secret index for retrieval by authorized users. Encryption can be used to protect data from theft or attack, but encryption alone is not...

AI Technical Summary

Problems solved by technology

This invention is a transformation of the full-text retrieval technology, which almost retains most of the full-text retrieval technologies, which is ideal in terms of retrieval efficiency and is easy to implement. Since only the index words of the index file are encrypted, although it can be retrieved in the Data security is protected to a certain extent, but it is difficult to resist common attack methods such as statistical attacks

Chinese invention patent application 200610124691.1 proposes a "ciphertext-based full-text retrieval system". This invention has improved security and usability, but it is still difficult to prevent statistical attacks and other attack methods

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