Research On Security And Efficient Integrity Auditing Methods In Cloud Environment

In the cloud environment,many enterprises and private users take advantage of reliability,stability,and computing efficiency of the cloud storage,choose to remotely store data to the cloud server.However,the cloud server may occur software or hardware failures and malicious actions by some administrators that may result in data corruption.Therefore,the extremely important security issue for users is how to ensure the integrity of remote outsourced data.At present,most integrity auditing schemes use a fixed auditing secret key to generate authenticators for data and upload them to the cloud server with data.However,these schemes do not take into account the security of the auditing secret key when the user is compromised,on the other hand,these schemes do not take into account the complex key management issues and system performance efficiency issues caused by the large increase of these data sources(users).This thesis addresses the problems mentioned above,and proposes two innovative schemes.The main research contents are as follows:(1)This thesis proposes an intrusion resilient public cloud auditing scheme with authenticator update.This scheme uses the authenticator update technology to periodically update the authenticators of data,ensuring the security of data when the user's auditing secret key is obtained,preventing malicious cloud server administrators from tampering with or even discarding files without being discovered.At the same time,the scheme uses random numbers to periodically update the private keys of users and third party auditor,which effectively protects the security of the auditing secret keys when both are compromised.In addition,the scheme uses random mask technology to protect the user's data privacy.Security analysis and performance analysis show that the performance of the scheme is acceptable.(2)This thesis proposes a multi source data integrity auditing scheme based on cloud fog smart grid system.This scheme combines the advantages of fog computing and cloud computing,and uses tag conversion technology to effectively solve the key management problem that third party auditor in the system need to obtain the public keys of a large number of data sources.At the same time,the scheme uses fog server to authenticate multiple data sources at the same time to implement multi source authentication,and a third party auditor can authenticate the data integrity of multiple data sources simultaneously,and the overall efficiency of the system can be improved.Finally,the scheme protects the identity privacy of each data source.Security analysis and performance analysis prove the security and efficiency of the scheme.