DICOM PS3.4 2024b - Service Class Specifications

Z.5 Association Negotiation

Association establishment is the first phase of any instance of communication between peer DICOM AEs. AEs supporting DICOM Query/Retrieve SOP Classes utilize Association establishment negotiation by defining the use of Application Association Information. See PS3.7 for an overview of Association negotiation.

SOP Classes of the Composite Instance Retrieve Without Bulk Data Service, which include retrieval services based on the C-GET operation, use the SCP/SCU Role Selection Sub-Item to identify the SOP Classes that may be used for retrieval.

Z.5.1 Association Negotiation for C-GET SOP Classes

Rules are as specified in Section C.5.3, except that the Extended Negotiation sub-item, if used, shall be used as defined in Section Y.5.1.1.


  1. Though converted images may be specified by their SOP Instance UID in the Request Identifier, which is always at the instance level, there remains a need for Extended Negotiation and specification of the Query/Retrieve View in order to assure that referential integrity is maintained within the returned SOP Instances (e.g., that a reference to a SOP Instance UID is to a converted image or not, as appropriate).

  2. Relational-retrieval is not applicable to this SOP Class, hence the Extended Negotiation Sub-Item does not include the use of that byte.

DICOM PS3.4 2024b - Service Class Specifications