Public Auditing Scheme for Integrity Verification in Distributed Cloud Storage System

Cloud storage provides a potential solution replacing physical disk drives in terms of prominent outsourcing services. A threaten from an untrusted server affects the security and integrity of the data. However, the major problem between the data integrity and cost of communication and computation is directly proportional to each other. It is hence necessary to develop a model that provides the trade-off between the data integrity and cost metrics in cloud environment. In this paper, we develop an integrity verification mechanism that enables the utilisation of cryptographic solution with algebraic signature. The model utilises elliptic curve digital signature algorithm (ECDSA) to verify the data outsources. The study further resists the malicious attacks including forgery attacks, replacing attacks and replay attacks. The symmetric encryption guarantees the privacy of the data. The simulation is conducted to test the efficacy of the algorithm in maintaining the data integrity with reduced cost. The performance of the entire model is tested against the existing methods in terms of their communication cost, computation cost, and overhead cost. The results of simulation show that the proposed method obtains reduced computational of 0.25% and communication cost of 0.21% than other public auditing schemes.

Persistent Cohesion with Advanced Ring Signatures for Shared Data in Cloud

Motivated by the exponential growth and the huge success of cloud data services bring the cloud common place for data to be not only stored in the cloud, but also shared across multiple users. Our scheme also has the added feature of access control in which only valid users are able to decrypt the stored information. Unfortunately, the integrity of cloud data is subject to skepticism due to the existence of hardware/software failures and human errors. Several mechanisms have been designed to allow both data owners and public verifiers to efficiently audit cloud data integrity without retrieving the entire data from the cloud server. However, public auditing on the integrity of shared data with these existing mechanisms will inevitably reveal confidential information—identity privacy—to public verifiers. In this paper, we propose a novel privacy-preserving mechanism that supports public auditing on shared data stored in the cloud. In particular, we exploit ring signatures to compute verification metadata needed to audit the correctness of shared data. With our mechanism, the identity of the signer on each block in shared data is kept private from public verifiers, who are able to efficiently verify shared data integrity without retrieving the entire file. In addition, our mechanism is able to perform multiple auditing tasks simultaneously instead of verifying them one by one. Our experimental results demonstrate the effectiveness and efficiency of our mechanism when auditing shared data integrity. Keywords: Public auditing, privacy-preserving, shared data, cloud computing

Public Auditing for Secure Cloud Storage based on DHT

Today cloud computing has been the most popular service enjoyed by people due to the easy maintenance provided by it. Cloud computing is cost-efficient and people pay according to the services they use. Many organizations are using cloud storage and the reason behind it is that the outsourcing services are provided by the cloud computing. Most of people do not trust the legality of the services provided by cloud (CSPs i.e. cloud service providers) because they are afraid of the security breach of their data. The public auditing of the data by their owners is a technique that can maintain the trust of people on cloud services. This research paper is about cloud storage services based on the distributed hash table (DHT).This is required for dynamic auditing of information as this is new two-dimensional data and Third-party Auditor (TPA) is responsible for recording the information to do dynamic auditing and the dimensional data is located at TPA. The computational costs gets reduced when the authorized information is migrated to the two dimensional data and the Cloud service provider shifts it to the TPA DHT has many structural advantages and the services can be updated efficiently. The comparison with the present system is also made and is assured that it is the security system for the cloud storage. To secure the data information by blinding it, random masking is provided as a proof for securing process. The authentication is done via hashing technique and integrity and performance checks are made with this authentication process.

Remote Data Possession Checking Scheme with Supporting Efficient Group User Authority Management for Shared Cloud Data

Under the shared big data environment, most of the existing data auditing schemes rarely consider the authorization management of group users. Meanwhile, how to deal with the shared data integrity is a problem that needs to be pondered. Thus, in this paper, we propose a novel remote data checking possession scheme which achieves group authority management while completing the public auditing. To perform authority management work, we introduce a trusted entity – group manager. We formalize a new algebraic structure operator named authorization invisible authenticator (AIA). Meanwhile, we provide two versions of AIA scheme: basic AIA scheme and standard AIA scheme. The standard AIA scheme is constructed based on the basic AIA scheme and user information table (UIT), with advanced security and wider applicable scenarios. By virtue of standard AIA scheme, the group manager can perfectly and easily carry out authority management, including enrolling, revoking, updating. On the basis of the above, we further design a public auditing scheme for non-revoked users’ shared data. The scheme is based on identity-based encryption (IBE), which greatly reduce the necessary certificate management cost. Furthermore, the detailed security analysis and performance evaluation demonstrate that the scheme is safe and feasible.