Research On Data Integrity Auditing Protocols For Cloud Storage

This is an era both of information and data explosion.The universal popularity of mobile intelligent devices and the emerging Internet of Things technology produce vast amounts of data,the acquisition,storage,management and analysis of which have greatly been beyond the process capability of traditional database.Cloud computing,which is an integration of traditional computer technologies and network technologies,is composed of distributed computing,parallel computing,network storage,virtualization and so on.Moreover,it provides an efficient way to manage and maintain the massive amounts of data.Because of the configurable computing resource sharing pool,ubiquitous access interface and pay-per-use model,cloud computing will definitely develop into the main computing model.However,there is concern for the cloud storage security,which impedes the widely adoption of cloud computing.Software bugs,hardware failures,malicious servers or any other attackers are all likely to corrupt the outsourced data.Therefore,it is necessary to work out a secure and efficient cloud auditing mechanism to authenticate the integrity and availability of the outsourced data.Based on the exisiting cloud auditing mechanisms,we work out two new shcemes,which provide more functionalities.The main constructions of this thesis are as follows:(1)In this thesis,we propose an identity-based proxy-data-outsourcing auditing protocol.The processing of data is mainly occupied by signing data blocks.By leveraging a viarant of IBAS scheme,this protocol can simultaneously realize functionalities of delegating the capability of signing data blocks to proxies and verifying a set of digital signatures in a batch manner.In this work,authorized proxies are able to produce,process and upload data on behalf of data owner.Auditors can authenticate integrity of multiple data blocks by verifying a correspongding aggregate signature.Moreover,proxies encrypt the data before uploading it to the cloud,which prevents the cloud server and the third party auditor from spying into the data.This protocol also supports batch auditing,which means that the data integrity verification for multiple proxies can be perfomed simultaneouosly.The batch auditing mechanism reduces both communication cost on the server side and computational cost on the auditor side.(2)In this thesis,we propose a cloud auditing protocol with multi-keyword search over encrypted data.The integrity,confidentiality and availability of the cloud data are guaranteed by combining cloud auditing mechanisms and keywords search technologies.In this work,we firstly upload data to cloud through a blind storage system to ensure the confidentiality of the data.Then,we build a data auditing mechanism based on PDP model to authenticate the integrity of outsourced data.Nextly,we construct an index for the keywords dictionary in the form of a hash table to achieve efficient keyword search.Eventually,we build a Merkle hash tree and utilize the bilinear mapping accumulator mechanism to verify the search result efficiently.