A Multi-keyword Ciphertext Sorting and Retrieval Method Based on α-Fork Index Tree

Abstract

The invention discloses a multi-keyword ciphertext sorting and retrieval method based on an α-fork index tree. The data owner first vectorizes plaintext documents through a vector space model; then constructs a binary clustering tree through a binary k-means clustering method , traversing its leaf nodes to obtain the clustering document sequence; then constructing the α-fork index tree from the bottom up based on the clustering document sequence; finally, outsource the encrypted document and index tree to the cloud server, and share the key with authorized users; authorized users pass The retrieval trapdoor sends a retrieval request to the cloud server, and the cloud server returns the retrieval result through a greedy depth-first retrieval algorithm, and the authorized user obtains the plaintext retrieval result after decryption. The protocol flow of the invention is simple, high in security, easy to implement, and beneficial to improving the retrieval efficiency of multi-keyword ciphertext sorting retrieval and realizing accurate retrieval.

Description

technical field [0001] The invention belongs to the field of cloud computing security, and in particular relates to a method for sorting and retrieving multi-keyword ciphertexts based on an α-fork index tree. Background technique [0002] In the environment of big data, how to quickly and effectively retrieve the information needed by users from massive data has become an urgent problem to be solved. With its high-quality computing, storage, and application capabilities, cloud computing technology has become a mainstream model in the IT industry. In the cloud environment, users outsource resource data services to the cloud server to minimize expenditure costs, and protecting user privacy, preventing data from being leaked, and ensuring the efficiency and effectiveness of data obtained from the cloud server have also become people's concerns. focus. [0003] The traditional solution to data leakage is to encrypt the original data, but this will make data utilization face se...

AI Technical Summary

Problems solved by technology

These schemes may be able to return sorted documents more accurately, but with the increase of the document cardinality, the space overhead of the index tree is large, and the pruning effect of the retrieval algorithm will also be reduced, resulting in a decrease in retrieval efficiency. Therefore, it is necessary to propose a Safe, efficient and effective multi-keyword ciphertext sorting retrieval method

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