====== Actor ======

[[dido:99_annexes:annex-b-terms-and-definitions:start|Go up to Terms and Definitions]]

===== Discussion =====

An Actor is an identifiable participant that performs or can perform an action or [[dido:99_annexes:annex-b-terms-and-definitions:r:role|Role]] within a defined context.

An Actor can be:

  * A person
  * A [[dido:99_annexes:annex-b-terms-and-definitions:u:user|User]]
  * An [[dido:99_annexes:annex-b-terms-and-definitions:o:organization|Organization]]
  * An organizational unit
  * A system
  * A service
  * A [[dido:99_annexes:annex-b-terms-and-definitions:n:node|Node]]
  * An automated process
  * An external participant
  * Another identifiable participant capable of performing an action or Role

An Actor can identify:

  * Its identity
  * Its name
  * Its description
  * Its Actor type
  * Its assigned Roles
  * Its responsibilities
  * Its permitted actions
  * Its prohibited actions
  * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:o:organization|Organizations]]
  * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:g:governance_domain|Governance Domains]]
  * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:p:policy|Policies]]
  * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:g:governance_policy|Governance Policies]]
  * Its [[dido:99_annexes:annex-b-terms-and-definitions:p:provenance|Provenance]]
  * Its [[dido:99_annexes:annex-b-terms-and-definitions:t:traceability|Traceability]]

An Actor performs actions through one or more assigned Roles. The applicable Role establishes the responsibilities, permissions, and expected behaviors governing those actions.

===== Definition =====

//identifiable participant that performs or can perform an action or [[dido:99_annexes:annex-b-terms-and-definitions:r:role|Role]] within a defined context//

===== Source =====

Adapted from:

  * [[dido:99_annexes:annex-b-terms-and-definitions:r:role|Role]]
  * DIDO Reference Architecture
  * DIDO Reference Implementation Conceptual Model
  * DIDO-TE draft Requirements Register

===== Note =====

An Actor differs from a [[dido:99_annexes:annex-b-terms-and-definitions:r:role|Role]]:

  * An Actor identifies the participant
  * A Role identifies the responsibilities, permissions, and expected behaviors assignable to the participant

One Actor can perform multiple Roles. Multiple Actors can perform the same Role.

An Actor differs from a [[dido:99_annexes:annex-b-terms-and-definitions:u:user|User]]:

  * An Actor performs an action or Role within a defined context
  * A User interacts with or uses a system, service, or Resource to achieve a purpose

A User is an Actor when the User performs an action or Role. An Actor is not necessarily a User.

An Actor differs from a [[dido:99_annexes:annex-b-terms-and-definitions:n:node|Node]]:

  * An Actor is any identifiable participant that performs an action or Role
  * A Node is an identifiable participant that performs one or more assigned Roles in a distributed system

Every Node can act as an Actor. An Actor is not necessarily a Node.

An Actor does not need to be human. Organizations, systems, services, Nodes, and automated processes can act as Actors.

Identifying an Actor does not establish authority to perform every action. The applicable Role, authorization, Policy, and Governance Policy determine the permitted actions.

===== Example =====

A DIDO-TE validation process involves the following Actors:

  * A User acting in the Test Operator Role
  * A Node acting in the Test Participant Role
  * A service acting in the Evidence Collection Role
  * A User acting in the Evaluator Role
  * An Organization acting as the Governing Authority

Each Actor performs different actions according to its assigned Role and the applicable Governance Policies.

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