====== P4-REQ-21-8-004 ======

[[dido:99_annexes:annex-d-requirements:part-04:start| Return to Requirements]]

===== Statement =====

Each interaction realization SHALL identify the DDS Topic or Topics used.

===== Source =====

Part 4, Section 21.8: Interaction Pattern Realization Requirements.

===== Rationale =====

DDS Topics provide the Phase 0 communication mechanism used to realize applicable logical exchanges within an interaction pattern.

Identifying those Topics makes the communication path explicit and allows the interaction realization to be reviewed against the Communication Endpoint mappings defined elsewhere in Part 4.

===== Applies To =====

This requirement applies to:

  * Phase 0 interaction realizations;
  * DDS Topics;
  * publishers and subscribers; and
  * Communication Endpoint mappings.

===== Verification =====

Verification SHALL confirm that each interaction realization identifies the DDS Topic or Topics used.

Verification activities should include review checks confirming that:

  * every required exchange has an identified Topic;
  * Topic mappings agree with applicable Communication Endpoints;
  * publishers and subscribers are compatible; and
  * no ungoverned exchange is introduced.

===== Traceability =====

This requirement connects interaction realizations to the DDS Topic mappings that implement their communication exchanges.

Related requirement identifiers:

  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-8-003]]
  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-8-005]]
  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-5-001]]

Related source section:

  * [[fxdemo:04-part:21-phase-0-implementation-requirements:21-8-interaction-pattern-realization-requirements:start]]

===== Status =====

Draft

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