An insider threat aware access control for cloud relational databases

The request-response paradigm that consists of policy decision points (PDPs) and policy enforcement points (PEPs) is used for access control in Cloud computing. The model uses PEP-side caching to increase the availability and reduce the processing overhead on PDP. This paper shows that using PEP-side caching can be exploited by insiders to bypass cloud access control mechanisms, which increases insider threat in cloud computing. To overcome this problem, the paper proposes a manageable model that detects and prevents insider threat at PEP side with minimum overhead on the performance of PEP and PDP. The model has been extensively tested and the results show its effectiveness in mitigating insider threat. Moreover, the experiments demonstrate that the overhead posed by the model on PEP and PDP is low. Lemmas, theorems and algorithm have been provided to show the correctness and the applicability of the proposed approach.