Blockchain-based Enhancement Mechanism On Data Integrity For Cloud Storage

In recent years,with the development of big data technology,cloud storage technology has been continuously applied and in an increasingly broad direction,leading to an explosive growth in the number of enterprises and individuals who host their data or applications on cloud storage platforms.However,as enterprises and individuals accelerate the transfer of their data to cloud storage data centers,the actual control of cloud storage users over their data is gradually diminishing.In the cloud storage model,once the servers in the cloud storage data center fail in security,users’ data stored in the cloud can also suffer serious threats,with the biggest challenge facing them being ensuring the integrity of their cloud data.When user data is stored in the cloud,data integrity may be compromised due to software failure,hardware damage,or malicious user sabotage,and cloud service providers may conceal these phenomena to maintain their reputation,which may all be fatal threats to user data.For the study of cloud storage data integrity verification mechanism,the mainstream approach adopted by existing cloud storage platforms is to store the data corresponding integrity evidence together with the original data,and then verify the integrity of the data through the integrity evidence before using the data.This approach does not take into account that the data integrity evidence may also change with the change of data,such as malicious users may change the corresponding data integrity evidence at the same time when changing the original data to cover the change,in this case the system can still successfully pass the integrity verification,resulting in the inability to identify the damage to the original data in this way,and the integrity protection mechanism fails.There are also some solutions that use third-party databases to store data integrity evidence,but ordinary third-party databases still face the aforementioned threats,which only increase the difficulty of attack.Inspired by the characteristics of blockchain technology such as non-tamperable,non-deletable and traceable,this thesis introduces blockchain technology into the data integrity verification mechanism of cloud storage,and the core idea is to save the data integrity evidence into the blockchain network to ensure that the data integrity evidence is not tampered with.This approach can ensure that data integrity evidence can be stored securely,and thus ensure the continuous effectiveness of data integrity verification mechanism in cloud storage.In the protection of data integrity,when data integrity is detected to be broken,it means that the data recovery mechanism is activated.Most existing cloud storage platforms use a highly redundancy data multi-copy mechanism.Although this approach can guarantee data recovery when a copy is damaged,it also has a serious problem of extra space occupation,which makes the challenge of high storage cost in actual use.To address these problems,this thesis proposes to use the erasure coding technique instead of the multi-copy mechanism to reduce the storage cost of the cloud storage platform while ensuring data availability.In addition,the erasure code decentralizes the data in the cloud storage in a more fine-grained manner,which reduces the risk of one-time corruption of data in the cloud platform to a certain extent.In summary,this thesis proposes a blockchain-based enhancement mechanism on data integrity for cloud storage,which securely stores data integrity evidence through a blockchain network to ensure the effectiveness of the integrity verification mechanism,divide data into blocks and encodes blocks through the erasure code technology to ensure that data can be effectively recovered after the integrity is broken under the premise of reducing storage cost.At last,combines the advantages of both technologies to achieve the enhancement of data integrity in the cloud storage environment.The main work of this thesis is:1)This thesis proposes a method that combines the blockchain technology with the data integrity detection of cloud storage to realize the safe storage of the data integrity evidence of cloud storage.Based on the characteristics that blockchain can not be deleted and tampered with,this method provides a reliable guarantee for the storage of data integrity evidence and solves the problem of insufficient protection of data integrity evidence.2)Using erasure code technology to fault tolerance of cloud storage data,using reed-solomon code to divide and distributed store data,can provide the same fault tolerance rate as multi copy technology,reduce the storage cost of cloud storage,and also realize the repair and restoration of data after integrity is damaged.3)Combining the above methods,this thesis proposes a method to enhance the data integrity protection in cloud storage.This method is an independent method and has loose coupling with the cloud storage platform itself.Users can adapt different cloud storage platforms according to their requirements.It can also achieve the effect of enhancing the data integrity protection in cloud storage,and has good universality and portability.The method is implemented and applied to HDFS cloud storage system,and used the open source data set to test the function and performance,which proves the effectiveness and feasibility of the method.