Agent-based Security And Privacy Cooperative Protection Mechanism In Cloud Computing Environment

In cloud-based storage systems,encryption is a commonly used strategy to protect data privacy,but encryption alone cannot resist all types of attacks.For example,an attacker can infer private information by observing user access patterns to data,Which includes the importance of the data,the relevance of the data,and then analyzes the information to discover more private information of the user,even the content of the encrypted data.Oblivious Random Access Machine(ORAM)is an encryption scheme that can be used to hide the data access mode of IO operations.ORAM obfuscates each access process,making it indistinguishable from random access,obscuring information such as access operations,access locations,and the probability of users accessing data in real access,thereby protecting user privacy from the level of access patterns.In the existing ORAM-based cloud storage system,after each access operation,moving the data blocks does not completely eliminate the privacy leakage caused by the protection access mode,for example,the association between multiple data blocks The read and write operations may leak the correlation between the data blocks.Multiple consecutive read and write operations on the same data block allow the server to observe the importance of the data blocks,which will cause the user's privacy to a certain extent.In response to the security and privacy protection issues in cloud storage systems,the main research work and innovations in this article include the following two points:First,for the privacy leakage caused by the associated read and write operations between multiple data blocks,this paper proposes to use the buffer pool technology and sliding window protocol to solve.Establish a read and write buffer pool for the client's access request sequence,and set a sliding window for the client's read and write operations.According to the number of free positions in the buffer pool,the access request of the user in the scheduling request queue is entered into the buffer,and the user's access sequence is not executed immediately after entering the buffer pool,but is delayed for a certain period of time.After a certain amount,through the sliding window algorithm,for the access within the sliding window,parallel processing is performed in a random order.Secondly,in view of the privacy leakage caused by multiple consecutive reads and writes of the same data block,this article proposes to add some false access to the real access to confuse the server observation.For multiple read \ write operations of the same data block,some random access to other data blocks is added to it.Then,the fixed read and write mode in the original access can be broken,and the security and security of the user access mode can be enhanced.Privacy.Through simulation experiments,it is shown that the storage system based on Agent-ORAM proposed in this paper is gradually increasing with the increase of the number of concurrent clients,and the average response time of the corresponding clients is also gradually decreasing.This article also compares the improved algorithm with the Oblivistore system and Tao Store system.Through comparative analysis,the system in this article can protect the privacy of user access patterns,but there is a certain degree of sacrifice in performance.Therefore,when designing a cloud storage system,you need to Find a balance between the two.