Secure Cloud Storage Research Articles

Dynamic multiple copies adaptive audit scheme based on DITS

Multi-copy storage can effectively improve the security of cloud storage. To resolve the problem of dynamic security audit of multi-copy data in cloud, this paper proposes a dynamic multi-copy adaptive audit scheme (DMCAA) based on dynamic index table structure (DITS). In order to achieve the correctness and completeness detection of multiple copies, the data blocks and the corresponding location index information are connected to generate a duplicate file. The audit process is divided into two parts, one is the third-party audits and the other is client audits. When auditing, in order to prevent collusion attacks as well as to improve the audit accuracy, the third-party auditors apply the challenge-response mode to detect the data block labels, and the client auditor applies the adaptive audit algorithm to retrieve the index information of the data blocks. Finally, to prevent replacement and replay attacks, the version number and block number of the file information are added to the block label. Through theoretical analysis and experimental comparison, the scheme is more secure in verifying the integrity of dynamic data and the correctness of the multi-copy data, which can effectively prevent the existing data threats.

A Secure Enhanced Key-Policy Attribute-Based Temporary Keyword Search Scheme in the Cloud

Attribute-based keyword search (ABKS), as an important type of searchable encryption, has been widely utilized for secure cloud storage. In a key-policy attribute-based temporary keyword search (KP-ABTKS) scheme, a private key is associated with an access policy that controls the search ability of the user, while a search token is associated with a time interval that controls the search time of the cloud server. However, after a careful study, we uncover that the only existing KP-ABTKS construction [1] is not secure. Through two carefully designed attacks, we first show that the cloud server can search the ciphertext in any time. As a result, their scheme cannot support temporary keyword search. To address this problem, we present an enhanced KP-ABTKS scheme and prove that it is selectively secure against chosen-keyword attack in the random oracle model. The proposed scheme achieves both fine-grained search control and temporary keyword search simultaneously. In addition, the performance evaluation indicates that our scheme is practical.

Providing a Public Auditing Cryptographic Approach in Cloud Computing

Cloud computing provides data storage facility to its users in cloud storage servers based on the required payment. Using public auditability, we can check the behaviour of data in the cloud. The auditing protocol must measure less communication cost incurred by the auditor and the cloud server. Third party auditor is responsible for the authentication of secret files in cloud system on behalf of the data owner. This paper describes an auditing system for secure cloud storage systems using privacy preservation scheme. The data auditability technique allows the user to make the data integrity check using a third party. The public auditability system permits the TPA to check the cloud information without downloading the original data from the user. This process involves profiling the data and evaluating the impact of inadequate quality data which results in the performance of the organisation.

Secure Content-Based Image Retrieval in the Cloud With Key Confidentiality

Owing to the rapid development of cloud services and personal privacy demand, secure cloud storage services and search over encrypted datasets have become an important issue. Recently, the leaking of images such as identification and driver's licenses catches much attention. The trend towards secure computation has been widely discussed, especially asymmetric scalar-product-preserving encryption (ASPE) and homomorphic encryption (HE). Although ASPE have ability to encrypt and determine the similarity between ciphertexts efficiently, it is not a practical methodology due to its assumption that the users are fully trusted in real world and it also may have key leakage problem. Contrary to ASPE, HE can execute addition and multiplication in the encrypted domain and solve key leakage problem. Hence, in this paper, we combine the opinions of HE and ASPE to propose new privacy-preserving content-based image retrieval with key confidentiality scheme against the attacks from data owner, cloud server and users. Our privacy preserving image retrieval scheme is developed under strong threat model that is close to real world. Furthermore, to the best of our knowledge, our work is the first one that developing scheme under the assumption that all the entities involved in privacy-preserving image retrieval system are semi-trusted. Our scheme ensures the confidentiality of key and privacy of query information at the same time. In addition, we provide a lightweight verification to check whether the search query is fake or not. Finally, the experiment results show that the computation overheads and search precision are acceptable at the same time.

Data access control algorithm based on fine-grained cloud storage

In order to ensure the cloud storage security and achieve fine-grained data access control, a new fine-grained data access control algorithm is established based on CP-ABE algorithm. The basic theory of CP-ABE algorithm is studied in depth, and then the fine-grained cloud storage controlling scheme based on digital envelope is put forward. The new scheme construction process is given, and then the corresponding algorithm is designed. Simulation analysis is carried out, results show that the proposed data access control algorithm can effectively improve the searching efficiency of cipher text, and achieve fine-grained access under cloud storage environment.

Homomorphic Cryptosystems for Data Security in Cloud Storage

Cloud Computing enables users to use remote resources thus reduces the burden on local storage. However, the use of such services gives rise to new set of problems. The users have no control over the data which they have stored on those storages so to achieve data authentication with confidentiality is utmost important. As every user may not have that expertise so they can request for data verification task to Trusted Verifier (TV) which will be an authorized party to check the intactness of outsourced data. Since the data owner stores the data on the cloud in an encrypted format, it becomes difficult to check the integrity of the data without decrypting. But by using homomorphic encryption schemes the integrity checking can be made possible without original copy. In this paper, we have given implementation and performance details of two homomorphic encryption schemes, Rivest Shamir Adleman (RSA) and Paillier. The RSA is multiplicative homomorphic scheme where the Paillier is additive homomorphic scheme. Both the algorithms are partially homomorphic thus limited in their functions. Due to homomorphic property of these algorithms, original contents will not get revealed in the verification process. This framework will achieve authentication of data by maintaining confidentiality.

New public auditing protocol based on homomorphic tags for secure cloud storage

SummaryOutsourcing datum to the cloud servers is more and more popular for most data owners and enterprises. However, how to ensure the outsourced datum to be kept secure is very important. Especially, how to check the outsourced datum's integrity is a very challenge problem. Until now, there are many cryptographic protocols proposed to solve this problem, such as (dynamic) provable data position protocol, (dynamic) proof of retrievability protocol, etc. Recently, Tian et al proposed a dynamic‐hash‐table‐based public auditing scheme for secure cloud storage, which aims at simultaneously supporting secure dynamic data updating and secure public auditing for cloud storage. However, we find a security flaw in this protocol; concretely, the signature algorithm for the data blocks in their protocol is not secure; the cloud servers can easily modify the outsourced data blocks without detecting. Finally, we give a new protocol by using homomorphic tags based on their protocol and roughly analysis its security.

A Secured Public Auditing Protocol with Dynamic Structure for Cloud Data

At present Cloud computing is a very successful paradigm for data computing and storage. It Increases the concerns about data security and privacy in the cloud. Paper covers cloud security and privacy research, while focusing on the works that protect data confidentiality and privacy for sensitive data being stored and queried in the cloud. As Survey enlist all the research carried out related to data security and users privacy preserving techniques in detail. Data sharing can be achieved with sensitive information hiding with remote data integrity auditing, propose a new concept called identity based shared data integrity auditing with sensitive information hiding for secure cloud storage. Initially every data would be outsourced to the cloud only after authorized or activated by the proxy. The key would be generated to the file randomly by the key generation Centre. The transaction details such as key mismatch, file upload and download, hacking details would be shown to the proxy and cloud server. If the match occurs, automatically file would be recovered by the user even if hacker access or tamper the file. The main motive is to ensure that when the cloud properly stores the user’s sanitized data, the proof it generates can pass the verification of the third party auditor. And the paper provides various research work done in the field

Cloud storage security assessment through equilibrium analysis

With ever greater amounts of data stored in cloud servers, data security and privacy issues have become increasingly important. Public cloud storage providers are semi-trustworthy because they may not have adequate security mechanisms to protect user data from being stolen or misused. Therefore, it is crucial for cloud users to evaluate the security of cloud storage providers. However, existing security assessment methods mainly focus on external security risks without considering the trustworthiness of cloud providers. In addition, the widely used third-party mediators are assumed to be trusted and we are not aware of any work that considers the security of these mediators. This study fills these gaps by assessing the security of public cloud storage providers and third-party mediators through equilibrium analysis. More specifically, we conduct evaluations on a series of game models between public cloud storage providers and users to thoroughly analyze the security of different service scenarios. Using our proposed security assessment, users can determine the risk of whether their privacy data is likely to be hacked by the cloud service providers; the cloud service providers can also decide on strategies to make their services more trustworthy. An experimental study of 32 users verified our method and indicated its potential for real service improvement.

Multiple Authority Based Data Fragmentation Technique for Providing Secure Storage in Cloud

The existing works on security storage in cloud computing cause overhead, data correctness issue, key escrow problem, single point of failure and so on. This develops Multiple Authority based Data Fragmentation Technique for providing Secure Storage in Cloud Computing. It aims to avoid the key escrow and single point of failure issues of secure storage. In this technique, the Cloud Service Provider (CSP) provides multiple services for a client, the trusted and verification authorities are responsible for jointly creating the master key and system parameters and the Cloud Data Owner (CDO) encrypts the documents using CP-ABE. In order to provide data recoverability, a file is divided into blocks and sectors. Probabilistic algorithm checks the integrity of fragmented file. By simulating, the proposed technique reduces the overhead and data failures.

A Provably Secure Distant Data Integrity Checking With Homomorphic Hash Function in Secure Cloud Storage

The cloud storage with user facilities like great data storage quality, higher computing, scalable and flexible has been one of the major application of cloud computing. Large number of data holders is subcontracting the files to the cloud. The cloud server being a public domain is not very reliable thus the data holders are required to find a reliable and trustworthy way to check the ownership of the data files that they subcontract on the cloud server which is present in a remote location. To tackle this drawback number of Distant Data Integrity Checking (DDIC) protocols is in the literature but these protocols have liabilities with respect to the data dynamics and the efficiency. This work recommends a novel DDIC protocol built across homomorphic-hash-function. This system gives a resistance against number of attacks like replay, replaces and falsifications. This work introduces the Operation-record-table(ORT) which is an optimized table resulting in keeping the constant cost for supporting the data variations and keep tracks of blocking the file operations.

Secure Cloud Storage of Text and Image Files by Giving Access Control to Users

Cloud computing is extensively used but it’s not completely trustworthy. It can be in terms of protecting or securing the confidential data from malicious attacks as well as from cloud providers. Also once the data is deployed on cloud, the user has no control over it. So rather than deploying the original text file the user encrypts the file and then uploads on the cloud. When this file needs to be shared with other it can be done using Cipher text Policy Attribute Based Encryption (CP-ABE). This gives the central access to the owner and secures the data from external attacks. Besides, the cloud provider serves both as the payee of resource consumption fee, lacking the transparency to data owners. So to reduce these factors a specific encryption strategy is been used and the time for encryption is also taken into account. The files are also encrypted by the priority that are given by the user during the file uploading section. A text file of size 1GB with the CP-ABE encryption strategy requires 174 seconds whereas encryption done using AES is 473 seconds and that of RSA is 330 seconds. Hence, this dissertation work proposes methodology to secure or protect encrypted cloud storage from Economic Denial of Sustainability attacks and give an efficient time constraint approach.

A Trusted Management Model for Secure Cloud Storage

A Trusted Management Model for Secure Cloud Storage

Reduction of Data Risk in Cloud Computing Through the Front Layer Security Mechanism

Background/objectives: The centralised computing defines cloud computation as centralised model which is responsible to provide the network access on-request basis to a shared pool of interconnected computation resources linked together. The same is done to provision in a quick manner and to be released with the minimal management effort or cloud provider interaction. It is a platform that is built to customer convenient interface with IT framework. The promise made by the cloud computing, especially shared cloud can be decked by security infraction which are indefeasible. Methods/statistical analysis: An encryption and decryption algorithms have been proposed so as to maintain the security of the private data that is being transmitted in the cloud scenario. Findings: The increasing necessity for the secure cloud storage being handled in a centralised fashion and thereby the enticing effects of the cryptography at client side help us in prioritising and combine them together, thereby naming an innovative mechanism for the private data as third-party security and regulation issues. Improvements/applications: The proposed work provides a more secure framework layer as security to the data, but still there are various aspects which need to be addressed in future. Proposed work is suitable only for selected private data rather than a huge data input by user on cloud, we can extend this work for different types of modules with timestamp encryption converted time and efficiency in future. In future, the technique of Each Word Secure Authentication would be added to improve cloud security on behalf of private. Based on the security solutions, we will demonstrate a secure new client-side framework with advanced algorithm implementations in this article.Keywords: Cloud Enhancement, EWSA, Cloud Server, Secure Cloud Platform

An identity-based online/offline secure cloud storage auditing scheme

Cloud storage has significantly reduced data management costs for data owners. However, loss of physical control over the data after outsourcing, triggers some security concerns such as data integrity. Provable Data Possession (PDP) protocols, enable data owners to audit the integrity of their outsourced data without the need to retrieve the file from cloud server. However, most existing PDP schemes require resource-constrained users to perform costly operations for generating metadata on file blocks. In online/offline PDP mechanisms introduced most recently, the user’s computation is divided into online/offline phases, where the costly operations are allowed to be carried out in the offline phase. The users only require to perform lightweight operations in the real-time online phase. In this paper, we propose an identity-based (ID-based) online/offline PDP protocol which not only has lightweight computations at the users side, but also removes the complex certificate management/verification costs caused by expensive Public Key Infrastructure. The proposed scheme is based on an ID-based online/offline signature designed in this paper. The protocol is proven to be secure against a malicious cloud server in the random oracle model. We also prove the privacy preserving property of the protocol in the sense that it leaks no information of the outsourced data to the public verifier during the protocol execution. Moreover, our mechanism supports batch verification of multiple auditing tasks and fully dynamic data operations, efficiently. Experimental results demonstrate fine efficiency of our scheme in comparison to the recent proposals.

Discretized Point Cheval–Stern Cryptosystem based Data Auditing for Secured Cloud Storage

Discretized Point Cheval–Stern Cryptosystem based Data Auditing for Secured Cloud Storage

Data Storage and Retrieval with Deduplication in Secured Cloud Storage

The Cloud Storage can be depicted as a service model where raw or processed data is stored, handled, and backed-up remotely while accessible to multiple users simultaneously over a network. Few of the ideal features of cloud storage is reliability, easy deployment, disaster recovery, security for data, accessibility and on top of that lesser overall storage costs which removes the hindrance of purchasing and maintaining the technologies for cloud storage. In this modern technology world, massive amount of data are produced in day to day life. So, it has become necessary to handle those big data on demand which is a challenging task for current data storage systems. The process of eliminating redundant copies of data thereby reducing the storage overhead is termed as Data Deduplication (DD). One of the ultimate aim of this research is to achieve ideal deduplication on secured data of client side. On the other hand as the client’s data are encrypted with different keys, the cross user deduplication is merely impossible as having a single key encryption among multiple user’s leads to an in secure system resulting in fragile to client’s expectations. The proposed research adapts Message Locked Encryption (MLE) technique that looks for redundant files in cloud before uploading the client’s file which eventually reduces the storage. Since the redundant files are swept, the network bandwidth is considerably reduced with respect to the redundant contents uploaded several times.

A Review: A Survey on Privacy Preserving for Secure Cloud Storage

A Review: A Survey on Privacy Preserving for Secure Cloud Storage

Hash function design for cloud storage data auditing

Cloud based storage is being widely used as a viable solution to the problem of data storage in contexts where financial and practical considerations prohibit the use of locally based hardware and software resources. User reservations and legal constraints however have given rise to questions about the verifiability of the integrity of the stored data, especially in the case of public cloud infrastructure. A new problem has hence arisen, that of auditing stored files in order to obtain Proof of Retrievability. Secure cloud storage systems are limited by the overheads they require in order to provide the required security levels. Combined use of cloud and local computational resources is necessary in order to enable the desirable user experiences. With increasing local processing capacities, the most significant relevance is encountered in the Big Data Processing paradigm. The volumes of data that need to be processed are overwhelming to such an extent that approaches which use unlimited amounts of power, for processing and storage are not feasible. This paper focuses on a recent study of hash function requirements for big data applications and an associated key – based hash function design technique that makes the real – time collection, summarization, analysis and decision making based on streaming data. A file auditing technique is proposed that uses fundamental big data mass processing operations in order to develop an efficient and reliable proof of recoverability algorithm.

A cloud compatible DNA coded security solution for multimedia file sharing & storage

The faster proliferation of software-defined cloud environments across the world for efficiently hosting enterprise-grade applications has led many organisations to embrace the cloud paradigm in a significant way. The cloud storage opportunities and possibilities are consistently expanding, wherein multimedia storage occupies the entire stage in the cloud. An essential emphasis on security owing to the nature of multiuser access to cloud credentials in many situations is necessary. The security and safety of data, while in transit, in rest, and while being used by applications, have to be guaranteed through proven technology solutions. Typically, image encryption is the standard way of securing and safeguarding images. The proposed three-layer image encryption scheme uses DNA coding along with chaotic logistic and tent maps for confusion and diffusion operations. Upon verification of user credentials, the storage of encrypted image is accomplished in Amazon S3 web services. The strength of encryption has been evaluated based on the parameters namely brute force attack, statistical, encryption quality, occlusion attack and computational complexity analyses which have proved the suitability of proposed scheme to secure cloud storage of images.