DICOM PS3.4 2019a - Service Class Specifications

CC.2.6.2 Service Class User Behavior

The SCU shall specify in the N-SET request primitive the UID of the UPS Instance for which it wants to set Attribute Values. Since all UPSs are created as instances of the UPS Push SOP Class, the Requested SOP Class UID in the N-SET request shall be the UID of the UPS Push SOP Class. See Section CC.3.1 for further details.

To N-SET a UPS instance currently in the SCHEDULED state, the Transaction UID Attribute shall not be present in the request. For a UPS instance in the IN PROGRESS state, the SCU shall provide the current Transaction UID (0008,1195) as an Attribute.

The SCU shall be permitted to set Attribute values as specified in Table CC.2.5-3. The SCU shall specify the list of Attributes for which it wants to set the Attribute Values. The SCU shall provide, with one or more N-SET request primitives, the Attribute values specified in Table CC.2.5-3.

When modifying a sequence, the SCU shall include in the N-SET request all Items in the sequence, not just the Items to be modified.

N-SET requests shall be atomic (indivisible) and idempotent (repeat executions have no additional effect). Since it is possible for an N-GET to occur between two N-SET requests, any given N-SET shall leave the UPS instance in an internally consistent state (i.e., when multiple Attributes need updating as a group, do this as multiple Attributes in a single N-SET request, not as multiple N-SET requests)

The SCU shall not set the value of the Procedure Step State (0074,1000) Attribute using N-SET. Procedure Step State is managed using N-ACTION as described in Section CC.2.1

The SCU shall create or set all Attributes to meet Final State requirements prior to using N-ACTION to set the value of Procedure Step State (0074,1000) to "COMPLETED" or "CANCELED". See Section CC. for further details.

Once the Procedure Step State (0074,1000) has been set to "COMPLETED" or "CANCELED" the SCU shall no longer modify the UPS SOP Instance.


The SCU can only set Attribute Values that have already been created with an N-CREATE request.

DICOM PS3.4 2019a - Service Class Specifications