DICOM PS3.4 2024d - Service Class Specifications |
---|
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 Query/Retrieve Service Class, which include query services based on the C-FIND operation, may use SOP Class Extended Negotiation Sub-Item to negotiate options such as Relational-queries and Enhanced Multi-Frame Image Conversion.
SOP Classes of the Query/Retrieve Service Class, which include retrieval services based on the C-MOVE and C-GET operations, may use the SOP Class Extended Negotiation Sub-Item to negotiate relational-retrieval and Enhanced Multi-Frame Image Conversion.
SOP Classes of the Query/Retrieve Service Class, 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.
The following negotiation rules apply to DICOM SOP Classes and Specialized DICOM SOP Classes of the Query/Retrieve Service Class that include the C-FIND operation.
The Association-requestor (query SCU role) shall convey in the A-ASSOCIATE request:
The Association-acceptor (query SCP role) of an A-ASSOCIATE request shall accept:
The SOP Class Extended Negotiation allows, at Association establishment, peer DICOM AEs to exchange application Association information defined by specific SOP Classes. This is achieved by defining the Service-class-application-information field. The Service-class-application-information field is used to define support for relational-queries, combined date time matching, fuzzy semantic matching of person names, timezone query adjustment, Enhanced Multi-Frame Image Conversion, Empty Value Matching, and Multiple Value Matching.
This negotiation is optional. If absent, the default conditions shall be:
The Association-requestor, for each SOP Class, may use one SOP Class Extended Negotiation Sub-Item. The SOP Class is identified by the corresponding Abstract Syntax Name (as defined by PS3.7) followed by the Service-class-application-information field. This field defines one or more sub-fields:
The Association-acceptor shall return a single byte field (single sub-field) if offered a single byte field (single sub-field) by the Association-requestor. The Association-acceptor may return either a single byte field (single sub-field) or a multiple byte field if offered a multiple byte field by the Association-requestor. A one byte response to a multiple byte request means that the missing sub-fields shall be treated as 0 values.
The restriction to return only a single byte field if that was all that was offered is because the original DICOM Standard only contained one byte and older systems may not be expecting more.
The Association-acceptor, for each sub-field of the SOP Class Extended Negotiation Sub-Item offered, either accepts the Association-requestor proposal by returning the same value (1) or turns down the proposal by returning the value (0).
If the SOP Class Extended Negotiation Sub-Item is not returned by the Association-acceptor then relational-queries are not supported over the Association (default condition).
If the SOP Class Extended Negotiation Sub-Items do not exist in the A-ASSOCIATE indication they shall be omitted in the A-ASSOCIATE response.
The SOP Class Extended Negotiation Sub-Item consists of a sequence of mandatory fields as defined by PS3.7. Table C.5-1 defines the Service-class-application-information field for DICOM Query/Retrieve SOP Classes and Specialized DICOM Query/Retrieve SOP Classes that include the C-FIND operation. This field may be either one or more bytes in length (i.e., item bytes 2 through 7 are optional).
Table C.5-1. SOP Class Extended Negotiation Sub-Item (Service-Class-Application-Information Field) - A-ASSOCIATE-RQ
The SOP Class Extended Negotiation Sub-Item is made of a sequence of mandatory fields as defined by PS3.7. Table C.5-2 defines the Service-class-application-information field for DICOM Query/Retrieve SOP Classes and Specialized DICOM Query/Retrieve SOP Classes that include the C-FIND operation. This field may be either one or more bytes in length (i.e., item bytes 2 through 7 are optional).
Table C.5-2. SOP Class Extended Negotiation Sub-Item (Service-Class-Application-Information Field) - A-ASSOCIATE-AC
DICOM PS3.4 2024d - Service Class Specifications |
---|