====== P4-REQ-21-9-005 ======

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

===== Statement =====

Each QoS profile mapping SHALL identify the expected reliability behavior.

===== Source =====

Part 4, Section 21.9: QoS Profile Requirements.

===== Rationale =====

Reliability behavior determines the expected delivery assurance for communication using the QoS profile.

Making the expectation explicit allows Phase 0 participants to use compatible communication behavior and supports review of whether an exchange requires reliable or other selected delivery semantics.

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

This requirement applies to:

  * QoS profile mappings;
  * DDS publishers;
  * DDS subscribers; and
  * applicable Topic exchanges.

===== Verification =====

Verification SHALL confirm that each QoS profile mapping identifies its expected reliability behavior.

Verification activities should include review checks confirming that:

  * the selected reliability expectation is stated;
  * publisher and subscriber reliability settings are compatible;
  * the selected behavior supports the communication purpose; and
  * deviations require review.

===== Traceability =====

This requirement establishes the reliability expectation associated with each Phase 0 QoS profile mapping.

Related requirement identifiers:

  * [[dido:99_annexes:annex-d-requirements:part-04:p4-req-21-9-004]]
  * [[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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