dido:03-dido-te:99-annexes:annex-c-requirements:03-functional-requirements:03-03-twin-node-requirements:twin-009-control-twin-interaction:twin-009b-specify-twin-interaction-direction

TWIN-009b — Specify Twin Interaction Direction

The DIDO-TE SHALL specify the permitted direction of each interaction identified for a Twin Relationship.

An interaction permitted within a Twin Relationship may be permitted in one direction, the reverse direction, or both directions.

For example, a Twin Realization may receive state information from a Node without permission to modify that Node.

Specified interaction direction prevents bidirectional interaction from being inferred from connectivity, observation capability, DDS publication and subscription relationships, or access to an interface.

Interaction direction remains distinct from interaction permission and authorization. TWIN-009a identifies permitted interactions. TWIN-009b specifies their direction. TWIN-009c establishes authorization requirements for Resource state changes.

Verification confirms that:

  1. Each permitted interaction has a specified direction.
  2. The specified direction identifies the originating and receiving entities.
  3. A unidirectional interaction does not imply permission for the reverse interaction.
  4. A bidirectional interaction is distinguishable from a unidirectional interaction.
  5. Communication connectivity, DDS publication and subscription relationships, interface availability, or Quality of Service compatibility do not override the specified interaction direction.
  6. The specified interaction direction is traceable to the governing Configuration.

Verification includes at least one unidirectional interaction and confirms that the reverse interaction is not treated as permitted.

This requirement establishes the permitted direction of interactions identified under TWIN-009a before evaluation of authorization or execution.

TBD

Draft

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  • dido/03-dido-te/99-annexes/annex-c-requirements/03-functional-requirements/03-03-twin-node-requirements/twin-009-control-twin-interaction/twin-009b-specify-twin-interaction-direction.txt
  • Last modified: 2026/08/22 14:25
  • by nick_dido