UCON

UCON is an acronym most often associated with Usage Control, a model in information security and access control. It represents a framework for enforcing access decisions not only at the moment of access but continually during a session, and it accommodates dynamic changes in user attributes, resource states, and environmental conditions.

The core idea of UCON is to extend traditional access-control models by incorporating ongoing decision making. It introduces obligations and conditions that must be satisfied for continued access, and it allows access rights to be affected by changes in attributes or context. The UCON model is commonly described with the ABC framework: Authorization, Binding, and Continuation. Authorization refers to the initial decision to grant access; Binding ensures that the decision remains enforceable as the session proceeds; Continuation means that each usage or event can be reevaluated and potentially revoked if requirements change.

Key benefits of UCON include finer-grained control, the ability to revoke or modify permissions during a session, and support for complex constraints such as time limits, usage quotas, or obligations that must be fulfilled by the requester. This makes UCON particularly relevant for environments with dynamic policies, such as cloud computing, mobile devices, and systems requiring adherence to regulatory obligations.

UCON is typically discussed as an evolution of ABAC (attribute-based access control) and related models, emphasizing the lifecycle of a usage decision rather than a single, static grant. While it is a specialized topic within security research, it provides a theoretical foundation for enforcing policies that adapt to changing conditions and user behavior. See also ABAC, RBAC, and policy-based access control.