Access control, as the name indicates is a security measure that regulates access to resources/confidential data by verification of access rights (credentials) of users. This paper is a survey of the existing access control mechanisms that enables a novice reader to understand the existing concepts and models, analyze their usage and limitations in order to develop better mechanism by building up on the existing models that will better adapt to meet the changes/advancements in technology. The study will further enable the development of a strong and attack resilient access models that are eventually the need of the hour.

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Access Control Mandatory Access Control Discretionary Access Control Role-based Access Control Rule-based Access Control Content-based Access Control.