The Hanging Protocol Query/Retrieve Service Class defines an application-level class-of-service that facilitates access to Hanging Protocol composite objects. It provides query and retrieve/transfer capabilities similar to the Basic Worklist Management Service Class and Query/Retrieve Service Class.
In order to serve as an SCP of the Hanging Protocol Query/Retrieve Service Class, a DICOM AE possesses information about the Attributes of a number of Hanging Protocol composite SOP Instances. The information is organized into a Hanging Protocol Information Model.
Two peer DICOM AEs implement a SOP Class of the Hanging Protocol Query/Retrieve Service Class with one serving in the SCU role and one serving in the SCP role. SOP Classes of the Hanging Protocol Query/Retrieve Service Class are implemented using the DIMSE-C C-FIND, C-MOVE and C-GET services as defined in PS3.7.
The semantics of the C-FIND and C-GET services are the same as those defined in the Service Definition of the Basic Worklist Management Service Class.
The semantics of the C-MOVE service are the same as those defined in the Service Definition of the Query/Retrieve Service Class, with the exception that there is only one level of retrieval.