====== P4-REQ-21-9-009 ======

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

===== Statement =====

Each QoS profile mapping SHALL identify the expected liveliness or availability behavior.

===== Source =====

Part 4, Section 21.9: QoS Profile Requirements.

===== Rationale =====

Liveliness and availability behavior supports detection of implementation participants that become unavailable, silent, or unable to perform their expected communication responsibilities.

Explicit expectations allow Phase 0 to align participant availability detection with the communication purpose and operational needs of the applicable Runtime Plane.

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

This requirement applies to:

  * QoS profile mappings;
  * DDS publishers;
  * DDS subscribers;
  * implementation participants; and
  * applicable health and operational behavior.

===== Verification =====

Verification SHALL confirm that each QoS profile mapping identifies its expected liveliness or availability behavior.

Verification activities should include review checks confirming that:

  * the expected behavior is stated;
  * applicable participant unavailability can be detected where required;
  * publisher and subscriber settings are compatible; and
  * the selected behavior supports the applicable Runtime Plane purpose.

===== Traceability =====

This requirement establishes the liveliness or availability expectation associated with each Phase 0 QoS profile mapping.

Related requirement identifiers:

  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-9-002]]
  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-9-010]]

Related source section:

  * [[fxdemo:04-part:21-phase-0-implementation-requirements:21-9-qos-profile-requirements:start]]

===== Status =====

Draft

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