Jin Wang¹, Ying Liu¹, Shuying Rao¹, R. Simon Sherratt², Jinbin Hu^1,*

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 3849-3865, 2023, DOI:10.32604/cmc.2023.037150

Abstract Data security and user privacy have become crucial elements in multi-tenant data centers. Various traffic types in the multi-tenant data center in the cloud environment have their characteristics and requirements. In the data center network (DCN), short and long flows are sensitive to low latency and high throughput, respectively. The traditional security processing approaches, however, neglect these characteristics and requirements. This paper proposes a fine-grained security enhancement mechanism (SEM) to solve the problem of heterogeneous traffic and reduce the traffic completion time (FCT) of short flows while ensuring the security of multi-tenant traffic transmission. Specifically, for short flows in DCN,… More >

Pooja Dhiman¹, Santosh Kumar Henge¹, Sartaj Singh¹, Avinash Kaur², Parminder Singh^2,3, Mustapha Hadabou^3,*

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 3297-3313, 2023, DOI:10.32604/cmc.2023.030558

Abstract This research paper puts emphasis on using cloud computing with Blockchain (BC) to improve the security and privacy in a cloud. The security of data is not guaranteed as there is always a risk of leakage of users’ data. Blockchain can be used in a multi-tenant cloud environment (MTCE) to improve the security of data, as it is a decentralized approach. Data is saved in unaltered form. Also, Blockchain is not owned by a single organization. The encryption process can be done using a Homomorphic encryption (HE) algorithm along with hashing technique, hereby allowing computations on encrypted data without the… More >

Zhengtao Liu^{1, *}, Yun Yang¹, Wen Gu¹, Jinyue Xia²

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 1233-1245, 2020, DOI:10.32604/cmc.2020.010846

Abstract Most cloud services are built with multi-tenancy which enables data and configuration segregation upon shared infrastructures. It offers tremendous advantages for enterprises and service providers. It is anticipated that this situation will evolve to foster cross-tenant collaboration supported by Authorization as a service. To realize access control in a multi-tenant cloud computing environment, this study proposes a multi-tenant cloud computing access control model based on the traditional usage access control model by building trust relations among tenants. The model consists of three submodels, which achieve trust relationships between tenants with different granularities and satisfy the requirements of different application scenarios.… More >

Zhengtao Liu^{1, *}, Yi Ying¹, Yaqin Peng¹, Jinyue Xia²

CMC-Computers, Materials & Continua, Vol.63, No.2, pp. 861-871, 2020, DOI:10.32604/cmc.2020.07142

Abstract Multi-tenant collaboration brings the challenge to access control in cloud computing environment. Based on the multi-tenant role-based access control (MTRBAC) model, a Temporal MT-RBAC (TMT-RBAC) model for collaborative cloud services is proposed. It adds the time constraint between trusted tenants, including usable role time constraint based on both calendar and interval time. Analysis shows that the new model strengthens the presentation ability of MT-RBAC model, achieves the finergrained access control, reduces the management costs and enhances the security of multitenant collaboration in cloud computing environment. More >

Zhengtao Liu^1,*, Jinyue Xia²

CMC-Computers, Materials & Continua, Vol.60, No.1, pp. 395-408, 2019, DOI:10.32604/cmc.2019.05627

Abstract Tenants in the cloud computing environment share various services, including storage, network, computing, and applications. For better use of services in the cloud computing environment, tenants collaborate in tasks, resulting in challenges to the traditional access control. This study proposes a cross-tenant role-based access control (CT-RBAC) model for collaborative cloud services. This model covers the CT-RBAC0, CT-RBAC1, CT-RBAC2, and CT-RBAC3 models. The model not only extends the RBAC model in the multi-tenant cloud computing mode but also includes four types of authorization modes among tenants. Consequently, the role inheritance constraint is increased, and fine-grained authorization access among trusted tenants is… More >