A Cost-Aware Method of Privacy Protection for Multiple Cloud Service Requests

In cloud computing environment, service requests usually carry some sensitive information that will be treated as privacy and cloud service request privacy leakage problem has become a hotspot of cloud security research. Existing studies assumed that potential attackers only collected and dealt with the relevant information of single service request sequence, they did not distinguish the emphasis degree of users for these information. When applying directly to the scenes of multiple cloud service requests privacy protection, their strategies couldn´t meet the needs of protection due to the limitations of their analytical perspective, and their cost would also increase. In this paper, we propose a method of sensitive information relation description and privacy measurement that caters to multiple cloud service requests, and conduct privacy leakage risk assessment under this scenario based on D-S evidence theory, then give the strategy of obfuscation choice and noise generation for multiple cloud service requests, finally build a cost-aware privacy protection framework for them. The simulation and analysis shows that our approach ensures the security of multiple service requests in cloud environment without significantly increasing the system overhead and saves the noise cost.