A certificate-free online/offline searchable ciphertext method

Abstract

The invention provides a certificate-free online / offline searchable ciphertext method, which separates a certificate-free searchable encryption process into offline and online phases, wherein the offline phase is independent of keywords, and the online phase requires the participation of keywords. After completing the necessary preparatory work, the data owner generates offline ciphertext and fileciphertext in offline phase, and generates online ciphertext in online phase and sends the offline ciphertext, file ciphertext and online ciphertext to the server. Before the data user retrieves thefile ciphertext, the offline trap gate is generated in the offline phase, the online trap gate is generated in the online phase, and then the offline trap gate and the online trap gate are sent to theserver. After the server passes the authentication, notify the data user to download the file ciphertext, otherwise, terminate the related operation. The invention is very effective for the data owner and the data user when the computing resources or the storage resources are limited, and the off-line stage and the on-line stage are successively carried out, respectively occupying the computing resources or the storage resources, thereby reducing the common occupying trouble.

Description

technical field [0001] The invention belongs to the technical field of network security, in particular to a certificate-free searchable ciphertext method, in particular to a certificate-free online / offline searchable ciphertext method. Background technique [0002] With the development of network technology and computer storage technology, network costs and storage costs have also been greatly reduced. Especially with the current cloud storage technology, more and more users are willing to outsource data, especially those with limited computing and storage resources. Mobile devices. The most important role in data outsourcing is the server, but the server is not safe and often becomes the target of network attacks. In order to protect the privacy and security of user data, the data owner encrypts the data before outsourcing the data, and then uploads the ciphertext to server, but the subsequent search and retrieval of ciphertext becomes troublesome, and searchable encryptio...

AI Technical Summary

Problems solved by technology

[0004] There are some deficiencies in the existing searchable encryption methods without certificates, one of which is that they fail to consider the limited computing or storage resources of users, especially the widespread use of mobile devices today, such as smartphones, if All calculations of searchable encryption are done online, which inevitably leads to low efficiency of searchable encryption due to limited computing or storage resources. There is currently no effective solution to this problem

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