METHOD AND SYSTEM FOR SIMILARITY SEARCH OVER ENCRYPTED DATA IN CLOUD COMPUTING

摘要

A similarity search method in a similarity search system for encrypted data in a cloud computing environment including a plurality of user devices, a cloud server, a plurality of data uploader devices, and a trust authority server is disclosed. In the cloud computing environment, the similarity detection method for encrypted data is performed by a trusted authority server. ) As an input value ), Select a random random number ( ), Select the public parameter ( Creating a setup step; The relying authority server takes the number of subfeatures (l) as input and uses l random values for the private key ( Generating a key; The data uploader device uses the secret key (k) of the data uploader device, ), The data to be encrypted (I), and the identifier of the data uploader device ( ) As an input value, the first cipher text ( ) And identifier ( Creating an encryption step; The data uploader device ) And identifier ( Transmitting c) to the cloud server; The user device has a secret key (k ') and public parameters ( ), And the second cipher text ( Trapdoor generation step of generating a); The user device has a second passphrase ( Transmitting c) to the cloud server; And the first cipher text received by the cloud server from the data uploader device and the user device ( ), Identifier ( ), Second pass phrase ( ), And the threshold ( ) As an input value, the first cipher text ( ) And the second pass phrase ( ) Is determined to be similar, the identifier ( ), A search step that returns).