policy decision point (QoS) (PDP)

The Policy Decision Point (PDP) defines the central rules from the Common Open Policy Service( COPS) in a network. It makes authorization decisions for system entities that request such decisions.

If a user attempts to gain access to a file or other resources on a server or network, the Policy Enforcement Point( PEP) informs other entities on the network about the user attributes. The decision is then made by the Policy Decision Point (PDP), which ultimately decides on authorization based on the user attributes. The Policy Enforcement Point then informs the user of the Policy Decision Point's decision.

Policy Decision Point is part of a policy-based access control system RBAC that decides whether to authorize a user's request or not based on the available information(attributes) and the applicable security policies.