The Composite Instance Root Retrieve Information Model is identified by the SOP Class negotiated at Association establishment time. The SOP Class is composed of both an Information Model and a DIMSE-C Service Group.
This SOP Class identifies the class of the Composite Instance Root Retrieve Information Model (i.e., not the SOP Class of the stored SOP Instances for which the SCP has information).
Information Model Definitions for standard SOP Classes of the Composite Instance Root Retrieve Service are defined in this Annex. A Composite Instance Root Retrieve Information Model Definition contains:
Entity-Relationship Model Definition
Key Attributes Definition
For any Composite Instance Root Retrieve Information Model, an Entity-Relationship Model defines a hierarchy of entities, with Attributes defined for each level in the hierarchy (e.g., Composite Instance, Frame)..
Attributes and matching shall be as defined in section Section C.2.2