An efficient attribute-based hierarchical data access control scheme in cloud computing

Nowadays, data outsourcing in the cloud is used widely and popularly by people. It also arises several security problems. To control access of outsourced data with different priority becomes an important research issue. Recently, Chen et al. proposed the first hierarchical access control scheme in cloud computing. However, they did not concern with the time-bound property. In some applications such as Pay-TV, the time-bound property is necessary because subscriber may subscribe some channels during one month. In this paper, we propose the first time-bound hierarchical key management scheme in cloud computing without tamper-resistant devices. The security analysis demonstrates that the proposed scheme is provably secure against outsider and insider attacks.

In order to protect user privacy, save storage overhead and implement flexible and fine-grained access control, a multi-authority CP-ABE access control scheme with hidden policy and constant length ciphertext is proposed, and the scheme proves to be CPA-secure under the security model. The user's private key is generated by multiple authorities to alleviate damage of broken authorities to the system. The central authority publishes public parameters, and generates signature tags for users and authorities. However, it does not participate in the generation of any master key or attribute private key, thus avoiding the key escrow problem. The access structure is hidden within the ciphertext, so that malicious users are unable to obtain sensitive information through the access structure, which effectively protects user privacy. In addition, this scheme realizes constant length ciphertext. The number of exponentiation operation for encryption and bilinear pairing operation for decryption are fixed. Finally, theoretical analysis and experimental results show that the performance of our scheme is significantly superior to that of comparable schemes.

Data stored in the Internet of Vehicles (IoV) face problems with ease of tampering, easy disclosure and single access control. Based on this problem, we propose an access control scheme for the IoV based on blockchain, trust values and weighted attribute-based encryption, called the Blockchain Trust and Weighted Attribute-Based Access Control Strategy (BTWACS). First, we utilize both local and global blockchains to jointly maintain the generation, verification and storage of blocks, achieving distributed data storage and ensuring that data cannot arbitrarily be tampered with. Local blockchain mainly uses Road Side Unit (RSU) technology to calculate trust values, while global blockchain is mainly responsible for data storage and access policy selection. Secondly, we design a blockchain-based trust evaluation scheme called Blockchain-Based Trust Evaluation (BBTE). In this evaluation scheme, the trust value of the vehicle node is based on four factors: initial trust, historical experience trust, recommendation trust and RSU observation trust. CRITIC is used to determine the optimal weights of four factors to obtain the trust value. Then, we use the Network Simulator version 3 (NS3) to verify the security and accuracy of BBTE, improving the recognition accuracy and detection rate of malicious vehicle nodes. Finally, by mining the association relationships between attribute permissions among various roles, we construct a hierarchical access control strategy based on weight and trust, and further optimize the access strategy through pruning techniques. The experiment results indicate that this scheme can effectively respond to gray hole attacks, defamation attacks and collusion attacks from other vehicle nodes. This method can effectively reduce the computing and transmission costs of vehicles and meet the access requirements of multiple entities and roles in the IoV.

While providing access control in a hierarchical access structure, a partially ordered set of security classes can be used to depict an access hierarchy. Data accessible to descendants of a particular security class should also be accessible to the users of that security class. Towards this, an access control scheme is proposed for providing dynamic hierarchical access control. In the proposed solution, the storage at the users is constant. The public key storage is equal to the size of the hierarchy. Also, deriving the decryption key of a descendant class involves constant cost at the users in the security class.

As the access control mode of notepad files cannot meet the requirements of risk control for sensitive file hierarchical access, this paper proposes an application classification-based detection method for abnormal access to sensitive files. The application classification and file classification, access control policy mapping, and basic and preset policy detection are designed. Combining the operating system’s identification control of different applications at runtime, we monitor the abnormal access of sensitive files by hierarchical applications. The cross-access experiment of different levels of application to different sensitive files verified the effectiveness and security of hierarchical access control strategy and sensitive file abnormal access detection and reduced the risk of disclosure of sensitive files.

Cloud computing is considered one of the most dominant paradigms in the Information Technology (IT) industry these days. It offers new cost-effective services on-demand such as Software as a Service (SaaS), Infrastructure as a Service (IaaS) and Platform as a Service (PaaS). However, with all of these services promising facilities and benefits, there are still a number of challenges associated with utilizing cloud computing such as data security, abuse of cloud services, malicious insider and cyber-attacks. Among all security requirements of cloud computing, access control is one of the fundamental requirements in order to avoid unauthorized access to systems and protect organizations assets. Although, various access control models and policies have been developed such as Attribute based Access Control (ABAC) and Role Based Access Control (RBAC) for different environments, these models may not fulfil cloud’s access control requirements. In this paper, an enhanced attribute-based access control based on strategy mechanism is proposed by introducing a strategy for providing access control to the users in the cloud environment.

Cloud computing offers storage, infrastructure, computing, networking, databases, platform, software, and analytics services over the Internet. It provides numerous benefits including scalability, cost management, broad access to resources, elasticity, resource pooling. Though cloud computing is mature and widely adopted computing model in software as well as non-software industries, it has several issues regarding security as it provides most of the cloud services over the public infrastructure. Denial of service (DOS), malware injection, insecure APIs, data loss, data breaches, hypervisor vulnerabilities, VM escape are a few major issues in cloud computing. In this paper, authors tried to provide a comprehensive analysis of critical security issues in cloud computing. Furthermore, this paper critically analyses the existing solutions to the various security issues in the cloud computing model.

In a time-bound cryptographic key assignment scheme, distinct temporal keys for distinct time periods are assigned to the channels in order to encrypt and decrypt the channels for secure broadcasting. It has numerous applications including the Pay-TV systems. In this paper, we aim to propose a novel time-bound hierarchical access control scheme for secure broadcasting, in which each user needs to store a distinct and unique user's private key, and hence each user in a channel group can subscribe for an individual channel. Our scheme reduces significantly the implementation cost and also improves the computational performance along with extra features. Through the informal and formal security analysis, it is shown that our scheme is secure against various known attacks including the collusion attack. As a result, our scheme is more secure and efficient as compared to other related schemes in the literature.

Background/Objectives: The rapid growth of cloud computing has become a remarkable in many sectors including educational sectors. Cloud computing is the essential tool, which can be used to enhance the accessibility of quality education.In realityusers of cloud computing in Saudi Arabia are facing many challenges due to lacks of regulation compliance, security, privacy, and confidentiality. Research in the field of challenges and barriers in cloud computing is very limited; moreover, there is very little information available in this area especially in legal aspects. Methods: This study focuses on the challenges and barriers, which affects cloud computing in higher education in the Kingdom of Saudi Arabia. The study applied a qualitative and quantitative method throughout the discussion and analysis on current issues and challenges in Cloud Computing in educational sectors in Saudi Arabia. Findings: Majority of the respondents agreed that privacy, security and confidentiality are the issues that need immediate attention of lawmaker. These issues and challenges act as a barrier for adoption of cloud computing in education sector in Saudi Arabia. There is no specific privacy protection law in the Kingdom of Saudi Arabia, only effective laws will avoid the challenges and barriers related to the privacy and security issues in cloud computing. Cloud computing provides an opportunity for the educational institutions to share the data with students, professors, and authorized person. Sharing of information needs strict regulations on data confidentiality, security and how well the privacy of the institution is maintained. Application: Different threats are involved when managing the privacy and sharing of data in the cloud. It is significant to determine the causes of issues and carry out a necessary solution to solve the problem. To ensure an appropriate balance between the number and strength of controls and the risks associated with cloud computing solutions, state agencies and organizations should work together. Keywords: Cloud Computing, Confidentially, Educational Sectors, Privacy, Regulations, Security

<p>Cloud computing services enabled through information communication technology delivered to a customer as services over the Internet on a leased basis have the capability to extend up or down their service requirements or needs. In this model, the infrastructure is owned by a third party vendor and the cloud computing services are delivered to the requested customers. Cloud computing model has many advantages including scalability, flexibility, elasticity, efficiency, and supports outsourcing non-core activities of an organization. Cloud computing offers an innovative business concept for organizations to adopt IT enabled services without advance investment. This model enables convenient, on-request network accessibility to a shared pool of IT computing resources like networks, servers, storage, applications, and services. Cloud computing can be quickly provisioned and released with negligible management exertion or service provider interaction. Even though organizations get many benefits of cloud computing services, many organizations are slow in accepting cloud computing service model because of security concerns and challenges associated with management of this technology. Security, being the major issues which hinder the growth of cloud computing service model due to the provision of handling confidential data by the third party is risky such that the consumers need to be more attentive in understanding the risks of data breaches in this new environment. In this paper, we have discussed the security issues, the challenges and the opportunities in the adoption and management of cloud computing services model in an organization.</p>

A major development in the field of access control is the dominant role-based access control (RBAC) scheme. The fascination of RBAC lies in its enhanced security along with the concept of roles. In addition, attribute-based access control (ABAC) is added to the access control models, which is famous for its dynamic behavior. Separation of duty (SOD) is used for enforcing least privilege concept in RBAC and ABAC. Moreover, SOD is a powerful tool that is used to protect an organization from internal security attacks and threats. Different problems have been found in the implementation of SOD at the role level. This paper discusses that the implementation of SOD on the level of roles is not a good option. Therefore, this paper proposes a hybrid access control model to implement SOD on the basis of permissions. The first part of the proposed model is based on the addition of attributes with dynamic characteristics in the RBAC model, whereas the second part of the model implements the permission-based SOD in dynamic RBAC model. Moreover, in comparison with previous models, performance and feature analysis are performed to show the strength of dynamic RBAC model. This model improves the performance of the RBAC model in terms of time, dynamicity, and automatic permissions and roles assignment. At the same time, this model also reduces the administrator’s load and provides a flexible, dynamic, and secure access control model.

Cloud Computing is a way to deal with fabricate the breaking point or incorporate capacities effectively without placing assets into new system, planning new staff, or approving new programming. They have various potential purposes of intrigue and various attempt applications and data are moving to open or half and half cloud. However, regarding some business-fundamental applications, the affiliations, especially considerable attempts, still wouldn't move them to cloud. The market gauge the Cloud Computing shared is as yet far behind the one expected. From the clients' perspective, Cloud Computing security concerns, especially data security and security confirmation issues, remain the basic inhibitor for gathering of Cloud Computing organizations. In this paper, we present a diagram on data security and security protection issues related with Cloud Computing over all periods of data life cycle. Firstly,, we moreover focus a related works and after that we show unpretentious components of Cloud Computing security issues, and a short time later data security and insurance affirmation issues, and a while later we display some present courses of action in cloud. Finally, we look at future work about data security and security affirmation issues in cloud. Keywords: cloud computing; security deployment; privacy protection infrastructure.

Job scheduling system problem is a core and challenging issue in Cloud Computing. How to use Cloud computing resources efficiently and gain the maximum profits with job scheduling. Job scheduling system is one of the Cloud computing service providers’ ultimate goals. In this paper, firstly, by analysis the differentiated QoS requirements of Cloud computing resources users’ jobs, we build the corresponding non-pre-emptive priority M/G/1 queuing model for the jobs.Then, considering Cloud computing service providers’ destination which is to gain the maximum profits by offering Cloud computing resources, we built the system cost function for this queuing model. After that, based on the queuing model and system cost function, considering the goals of both the Cloud Computing service users and providers, we gave the corresponding strategy and algorithm to get the approximate optimistic value of service for each job in the corresponding no-pre-emptive priority M/G/1 queuing model. Finally, we also provide corresponding simulations and numeral results.Analysis and number results show that our approach for job scheduling system can not only guarantee the QoS requirements of the users’ jobs, but also can make the maximum profits for the Cloud computing service providers.While the economic case for cloud computing is compelling, the security challenges it poses are equally striking. In this work we strive to frame the full space of cloud-computing security issues, attempting to separate justified concerns from possible over-reactions. We examine contemporary and historical perspectives from industry, academia, government, and “black hats”. We argue that few cloud computing security issues are fundamentally new or fundamentally intractable; often what appears “new” is so only relative to “traditional”computing of the past several years. Looking back further to the time-sharing era, many of these problems already received attention. On the other hand, we argue that two facets are to some degree new and fundamental to cloud computing: the complexities of multi-party trust considerations, and the ensuing need for mutual audit ability.

A Virtual Organization (VO) consists of some real organizations with common interests, which aims to provide inter organizational associations to reach some common goals by sharing their resources with each other. Providing security mechanisms, and especially a suitable access control mechanism, which enforces the defined security policy is a necessary requirement in VOs. Since VO is a complex environment with the huge number of users and resources, traditional access control models cannot satisfy VOs security requirements. Most of the current proposals are basically based on the attributes of users and resources. In this paper, we suggest using a combination of the semantic based access control (SBAC) model, and the attribute based access control (ABAC) model with the shared ontology of subjects' attributes in VOs. In this model, each participating organization makes its access control decisions according to an enhanced model of the ABAC model. However, access decision in the VO is made in more abstract level through an enhanced model of theSBACmodel. Using the ontology of users and resources in this model facilitates access control in large scale VOs with numerous organizations. By the combination ofSBACand ABAC, we attain their benefits and eliminate their shortcomings. In order to show the applicability of the proposed model, an access control system, based on the proposed model, has been implemented in Java using available APIs, including Sun's XACML API, Jena, Pellet, and Protege.

Cloud computing is the emerging way of computing that is being used by wide range of users. At present 80 % of workload is on cloud. There are many safety risks in cloud computing, “Cloud Security Alliance” (CSA) listed top 7 security threats as Maltreat and Obnoxious utilization of cloud, Uncertain API, Vicious Infiltrators, Distributed mechanism challenges, Information drop, Unidentified Risk Report and Account, Service and Traffic Hijacking. An IT company spends 42 percent of its funds for the security of cloud and 80 percent of the funds will be bounded to attain the solution to security issues. Researchers have proposed no. of solutions to cloud security. Proposed solutions fall under three primary categories, Cryptographic, data storage and data semantics. In this paper we have reviewed the concerns in cloud computing with some of the subsequent proposed models to tackle the security issues in cloud computing.