A Proactive Shredding Approach for Secure Deletion of Content in the Multi-Cloud Environment

Cloud computing has transformed data storage and management, offering scalability, flexibility, and cost-efficiency for applications. However, ensuring data security and maintaining performance in distributed cloud environments remain a significant challenge. Sensitive data stored in the cloud is vulnerable to unauthorized access, raising concerns about confidentiality and integrity. One particular vulnerability is caused by file deletion operations in computer systems, which usually only remove index entries, with the content of the files remaining on the disk. This can pose a potential threat to sensitive information in the cloud storage. This paper addresses the challenge by proposing a shredding-based approach for effective file management. The proposed approach proactively shreds files into independently meaningless shreds when storing a file in the cloud, and then distributes these shreds across multiple cloud sites. When the file is deleted, it is much harder to recover the content of the original file. A mathematical model is developed to perform shredding and reconstruction efficiently. It is further enhanced by randomizing the shredding process and adding modifiers to improve security. The method addresses the security problem of files stored in the cloud from a different perspective, compared to traditional encryption-based methods. Performance evaluation demonstrated that the proposed method achieves a balance between security and efficiency. The method is further evaluated using FABRIC infrastructure, and the results show that the shredding overhead is insignificant, and the approach can be used in practical cloud-based systems.