US 12,381,724 B2
Data maximum/minimum value aggregation method and system for privacy protection
Song Han, Hangzhou (CN); Siqi Ren, Hangzhou (CN); Xiaoli Chen, Hangzhou (CN); Zhibo Wang, Hangzhou (CN); Liang Cai, Hangzhou (CN); Minghui Wu, Hangzhou (CN); Jinsong Han, Hangzhou (CN); Jianhong Lin, Hangzhou (CN); Shuai Zhao, Hangzhou (CN); Shudan Jin, Hangzhou (CN); Xuanxuan Xu, Hangzhou (CN); and Shen Wang, Hangzhou (CN)
Assigned to Hangzhou City University, Hangzhou (CN); Zhejiang Ponshine Information Technology Co., Ltd., Hangzhou (CN); ZHEJIANG UNIVERSITY, Hangzhou (CN); Hangzhou Hyperchain Technology Co., Ltd., Hangzhou (CN); and Zhejiang Gongshang University, Hangzhou (CN)
Filed by Hangzhou City University, Hangzhou (CN); Zhejiang Ponshine Information Technology Co., Ltd., Hangzhou (CN); ZHEJIANG UNIVERSITY, Hangzhou (CN); Hangzhou Hyperchain Technology Co., Ltd., Hangzhou (CN); and Zhejiang Gongshang University, Hangzhou (CN)
Filed on Mar. 30, 2023, as Appl. No. 18/128,924.
Claims priority of application No. 202210338016.8 (CN), filed on Mar. 31, 2022.
Prior Publication US 2023/0318822 A1, Oct. 5, 2023
Int. Cl. H04L 9/40 (2022.01); H04L 9/08 (2006.01)
CPC H04L 9/0869 (2013.01) [H04L 9/0825 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A data maximum/minimum value (max/min) aggregation method for privacy protection, comprising:
generating, by a trusted authority, a public key (N, g) and a private key (λ, μ) of a Paillier cryptosystem, exposing the public key (N, g), and sending the private key (λ, μ) to a control center through a secure channel;
encrypting, by a client, health data d of the client by using the public key (N, g), generating a health data report, and uploading the health data report to a fog node, over one or more aggregation periods, wherein in each aggregation period, the client uploads health data reports n times, an ith health data report received for an ith time is health data report ci, and ci=Enc(di);
determining, by the fog node, whether the health data report ci received for the ith time is equal to a health data report c1 received for a first time, wherein
when the health data report c; received for the ith time is equal to the health data report c1 received for the first time, a max/min report M of the health data is the health data report c1 received for the first time;
when the health data report ci received for the ith time is greater than or less than the health data report c1 received for the first time, obtaining, by the fog node, encrypted data Enc(l), and uploading the encrypted data Enc(l) to the control center;
decrypting, by the control center, the encrypted data Enc(l) by using the private key (λ, μ) to obtain decrypted data l, determining a value of a first generation number based on the decrypted data l, and sending the value of the first generation number to the fog node;
when the value of the first generation number is equal to a value of a second generation number, determining, by the fog node, that the max/min report of the health data is the health data report ci received for the ith time, wherein the second generation number is a random number generated when the fog node obtains the encrypted data Enc(l);
when the value of the first generation number is not equal to the value of the second generation number, determining, by the fog node, that the max/min report M of the health data is the health data report c1 received for the first time;
after each aggregation period ends, aggregating, by the fog node, the health data reports, to obtain an aggregated health data report C, and sending the aggregated health data report C and the max/min report M to the control center, wherein C=Πi=1nci, n is a total quantity of times of uploading the health data reports in one aggregation period; and
decrypting, by the control center, the aggregated health data report C and the max/min report M by using the private key (λ, μ), to obtain a time aggregation result and a max/min result of the health data.