A Framework for Protecting Cloud Users from Third Party Auditors

Cloud computing has merged to be a now computing paradigm that lets public to access shared pool of resources without capital investment. The users of cloud need to access resources through Internet in pay per use fashion. Thus there is increased use of storage services of cloud in the real world. This service is known as Infrastructure as a Service (IaaS). However, there are security concerns as this service runs in entrusted environment. To ensure data integrity many public verification or auditing schemes came into existence. Nevertheless, there is a concern when the so called Third Party Auditor (TPA) has malicious intentions. In such cases, protection is required against malicious TPAs. Towards this end, recently, Huang et al. proposed a scheme in which users can directly check the integrity of stored data using a feedback based audit scheme. TPA takes process proof from cloud server and gives feedback to cloud user. The feedback is unforgivable and the TPA cannot make any malicious attacks. Based on this scheme, in this paper, we implemented a prototype application that demonstrates the proof of concept. The empirical results are encouraging. DOI: 10.17762/ijritcc2321-8169.15065

Dynamic Provable Data Possession Protocols with Public Verifiability and Data Privacy

Cloud storage services have become accessible and used by everyone. Nevertheless, stored data are dependable on the behavior of the cloud servers, and losses and damages often occur. One solution is to regularly audit the cloud servers in order to check the integrity of the stored data. The Dynamic Provable Data Possession scheme with Public Verifiability and Data Privacy presented in ACISP'15 is a straightforward design of such solution. However, this scheme is threatened by several attacks. In this paper, we carefully recall the definition of this scheme as well as explain how its security is dramatically menaced. Moreover, we proposed two new constructions for Dynamic Provable Data Possession scheme with Public Verifiability and Data Privacy based on the scheme presented in ACISP'15, one using Index Hash Tables and one based on Merkle Hash Trees. We show that the two schemes are secure and privacy-preserving in the random oracle model.Comment: ISPEC 201

ACTIVE-HASH-TABLE BASED PUBLIC AUDITING FOR SECURE CLOUD STORAGE

Public auditing scheme for secure cloud storage based on dynamic hash table, which is a new two-dimensional data structure located at a third-party auditor (TPA) to record the data property information for dynamic auditing. Differing form the existing works, the proposed scheme migrates the authorized information from the cloud services provider to the TPA and thereby significantly reduces the computational cost and communication overhead. Our scheme can also achieve higher updating efficiency than the state of the art schemes. In addition, we extend our scheme to support privacy preservation by combining the homomorphic authenticator based on the public key with the random masking generated by the TPA and achieve batch auditing by employing the aggregate BLS signature technique. We formally prove the security of the proposed scheme and evaluate the auditing performance by detailed experiments and comparisons with the existing ones. The results demonstrate that the proposed scheme can effectively achieve secure auditing for cloud storage and outperform the previous schemes’ in computation complexity, storage costs, and communication overhead

Identity-based remote data integrity checking with perfect data privacy preserving for cloud storage

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Remote data integrity checking (RDIC) enables a data storage server, such as a cloud server, to prove to a verifier that it is actually storing a data owner’s data honestly. To date, a number of RDIC protocols have been proposed in the literature, but almost all the constructions suffer from the issue of a complex key management, that is, they rely on the expensive public key infrastructure (PKI), which might hinder the deployment of RDIC in practice. In this paper, we propose a new construction of identity-based (ID-based) RDIC protocol by making use of key-homomorphic cryptographic primitive to reduce the system complexity and the cost for establishing and managing the public key authentication framework in PKI based RDIC schemes. We formalize ID-based RDIC and its security model including security against a malicious cloud server and zero knowledge privacy against a third party verifier. We then provide a concrete construction of ID-based RDIC scheme which leaks no information of the stored files to the verifier during the RDIC process. The new construction is proven secure against the malicious server in the generic group model and achieves zero knowledge privacy against a verifier. Extensive security analysis and implementation results demonstrate that the proposed new protocol is provably secure and practical in the real-world applications.This work is supported by the National Natural Science Foundation of China (61501333,61300213,61272436,61472083), Fok Ying Tung Education Foundation (141065), Program for New Century Excellent Talents in Fujian University (JA1406

METHOD TO ACHIEVE SECURITY AND STORAGE SERVICES IN CLOUD COMPUTING

Cloud storage enables users to remotely store their data and enjoy the on-demand high quality cloud applications without the burden of local hardware and software management. Though the benefits are clear, such a service is also relinquishing users ‘physical possession of their outsourced data, which inevitably poses new security risks toward the correctness of the data in cloud. In order to address this new problem and further achieve a secure and dependable cloud storage service, we propose in this paper a flexible distributed storage integrity auditing mechanism, utilizing the homomorphism token and distributed erasure-coded data. The proposed design allows users to audit the cloud storage with very lightweight communication and computation cost. The auditing result not only ensures strong cloud storage correctness guarantee, but also simultaneously achieves fast data error localization, i.e., the identification of misbehaving server. Considering the cloud data are dynamic in nature, the proposed design further supports secure and efficient dynamic operations on outsourced data, including block modification, deletion, and append. Analysis shows the proposed scheme is highly efficient and resilient against Byzantine failure, malicious data modification attack, and even server colluding attacks

SECURE DEPENDABLE SELECTIVE STORAGE SERVICES AND SUPPORT FOR DYNAMIC DATA OPERATIONS IN CLOUD COMPUTING

Cloud computing has been envisioned as the next generation architecture of IT enterprise. It moves the application software and databases to the centralized large data centers where management of data and services may not be fully trustworthy. This unique paradigm brings out many new security challenges like, maintaining correctness and integrity of data in cloud. Integrity of cloud data may be lost due to unauthorized access, modification or deletion of data. Lacking of availability of data may be due to the cloud service providers (CSP), in order to increase their margin of profit by reducing the cost, CSP may discard rarely accessed data without detecting in timely fashion. To overcome above issues, flexible distributed storage, token utilizing, signature creations used to ensure integrity of data, auditing mechanism used assists in maintaining the correctness of data and also locating, identifying of server where exactly the data has been corrupted and also dependability and availability of data achieved through distributed storage of data in cloud. Further in order to ensure authorized access to cloud data a admin module has been proposed in our previous conference paper, which prevents unauthorized users from accessing data and also selective storage scheme based on different parameters of cloud servers proposed in previous paper, in order to provide efficient storage of data in the cloud. In order to provide more efficiency in this paper dynamic data operations are supported such as updating, deletion and addition of data

ARPA Whitepaper

We propose a secure computation solution for blockchain networks. The correctness of computation is verifiable even under malicious majority condition using information-theoretic Message Authentication Code (MAC), and the privacy is preserved using Secret-Sharing. With state-of-the-art multiparty computation protocol and a layer2 solution, our privacy-preserving computation guarantees data security on blockchain, cryptographically, while reducing the heavy-lifting computation job to a few nodes. This breakthrough has several implications on the future of decentralized networks. First, secure computation can be used to support Private Smart Contracts, where consensus is reached without exposing the information in the public contract. Second, it enables data to be shared and used in trustless network, without disclosing the raw data during data-at-use, where data ownership and data usage is safely separated. Last but not least, computation and verification processes are separated, which can be perceived as computational sharding, this effectively makes the transaction processing speed linear to the number of participating nodes. Our objective is to deploy our secure computation network as an layer2 solution to any blockchain system. Smart Contracts\cite{smartcontract} will be used as bridge to link the blockchain and computation networks. Additionally, they will be used as verifier to ensure that outsourced computation is completed correctly. In order to achieve this, we first develop a general MPC network with advanced features, such as: 1) Secure Computation, 2) Off-chain Computation, 3) Verifiable Computation, and 4)Support dApps' needs like privacy-preserving data exchange

Enhancing Auction Systems with Blockchain Technology

This research paper examines the use of blockchain technology in auction systems. Traditional auction systems face issues related to trust, transparency, and security. Blockchain offers a decentralized and immutable solution that can enhance the efficiency, security, and transparency of auctions. The paper provides an overview of blockchain technology and identifies the challenges in traditional auctions that blockchain can address. It explores existing blockchain-based auction systems and evaluates their effectiveness in mitigating issues such as bid manipulation and fraud. The impact of blockchain on auction participants is also discussed, including benefits like increased trust and reduced transaction costs, as well as challenges related to adoption and scalability. The paper considers both theoretical and practical aspects, analyzing case studies and implementation challenges. It concludes by summarizing the key findings and suggesting future research directions to advance the application of blockchain in auction systems. The auction contract allows users to place bids and determine the highest bidder within a specified time period. The contract also provides functionality for canceling the auction and finalizing it by transferring the funds to the appropriate recipients

Droplet: Decentralized Authorization for IoT Data Streams

This paper presents Droplet, a decentralized data access control service, which operates without intermediate trust entities. Droplet enables data owners to securely and selectively share their encrypted data while guaranteeing data confidentiality against unauthorized parties. Droplet's contribution lies in coupling two key ideas: (i) a new cryptographically-enforced access control scheme for encrypted data streams that enables users to define fine-grained stream-specific access policies, and (ii) a decentralized authorization service that handles user-defined access policies. In this paper, we present Droplet's design, the reference implementation of Droplet, and experimental results of three case-study apps atop of Droplet: Fitbit activity tracker, Ava health tracker, and ECOviz smart meter dashboard