====== 7.4 QoS Profiles as Phase 0 Communication Behavior Controls ====== [[fxdemo:04-part:07-phase-0-technology-selection-and-implementation-context:start | Go To Phase 0 Technology Selection and Implementation Context ]] Phase 0 uses Quality of Service (QoS) profiles to control selected communication behaviors for [[dido:99_annexes:annex-b-terms-and-definitions:d:dds|DDS]] Topics, publishers, subscribers, and related implementation participants. Quality of Service (QoS) profiles define implementation-level communication behavior such as reliability, durability, ordering, liveliness, history, resource limits, and related DDS concerns as needed for Phase 0. The QoS profile assigned to a Topic or participant must support the [[dido:99_annexes:annex-b-terms-and-definitions:r:runtime_plane|Runtime Plane]] purpose and interaction expectations associated with the corresponding FX logical [[dido:99_annexes:annex-b-terms-and-definitions:l:logical_communication_endpoint|Communication Endpoint]]. Quality of Service (QoS) profiles do not redefine Runtime Planes or logical interaction patterns. They provide implementation controls that help realize selected logical communication expectations. Phase 0 defines Quality of Service (QoS) profiles only at the level needed for the demonstration baseline. Later development phases may extend, refine, supersede, or replace the Phase 0 Quality of Service (QoS) profiles. ---- © 2026 Dido Solutions, Inc. and Jackrabbit Consulting, Inc.