Upon receipt of the N-ACTION request, the SCP shall return, via the N-ACTION response primitive, the N-ACTION Response Status Code applicable to the associated request (see Table KK.2.2.3-1). A Success status conveys that the SCP has successfully received the request. A Warning status conveys that the SCP has successfully received the request, but might not process some of the requested parameters. A Failure status conveys that the SCP is not processing the request.

For Action Type "Initiate" (Action Type ID = 11), the SCP shall return a Failure Status Code of 0212H "Mistyped argument" if the SCP does not support all of the character sets identified in Specific Character Set (0008,0005), or all of the matching mechanisms identified in Extended Matching Mechanisms (0008,040F), or the identified Inventory Level (0008,0403); additional explanation may be returned in Error Comment (0000,0902). The SCP shall return a Warning Status Code of B010H "Attribute List warning - One or more of Key Attributes are not supported for matching" if one or more of the Key Attributes specified in the Scope of Inventory Sequence (0008,0400) are not supported for matching, and shall return the list of unsupported Attributes in Attribute Identifier List (0000,1005).

If the SCP conveys a Success or Warning status for Action Type "Initiate" (Action Type ID = 11), it shall initiate production of an Inventory and periodic status reporting in accordance with the parameters of the Scope of Inventory Sequence (0008,0400) and Inventory Level (0008,0403) provided in the N-ACTION request. The Inventory SOP Instance(s) produced to satisfy the N-ACTION request shall include the Transaction UID (0008,1195). The Scope of Inventory in the produced Inventory SOP Instances shall include only those Key Attributes that were supported for matching. Any value provided by the SCU for Inventory Purpose (0008,0401) shall be included in the produced Inventory SOP Instances.

The produced Inventory SOP Instance(s) may include existing Inventory SOP Instances by reference in the Incorporated Inventory Instance Sequence (0008,0422). Existing Inventory SOP Instances that contribute to satisfying the N-ACTION request may be included by reference, but since they were not produced in response to the request, they would not contain its Transaction UID (0008,1195), and may have a different Scope of Inventory, or Inventory Purpose (0008,0401).

The SCP shall produce at least one Inventory SOP Instance (at the root of the tree of referenced SOP Instances) upon reaching the COMPLETE state.

If the SCP encounters a failure when producing the Inventory, it may attempt to complete the encoding into an Inventory SOP Instance of Study records already obtained, and set Inventory Completion Status (0008,0426) in that SOP Instance to "FAILURE".

If the SCP conveys a Success status for Action Type "Request Status" (Action Type ID = 12), it shall initiate sending an N-EVENT-REPORT with Event Type "Inventory Status" (Event Type ID = 12).

If the SCP conveys a Success status for Action Type "Cancel" (Action Type ID = 13), it shall stop production of the Inventory associated with the Transaction UID (0008,1195). If the Cancel request includes Retain Instances (0008,0415) with value "N", the SCP may delete any Inventory SOP Instances associated with the Transaction UID (0008,1195). If the Cancel request includes Retain Instances (0008,0415) with value "Y", the SCP shall complete the encoding into an Inventory SOP Instance of Study records already obtained, and set Inventory Completion Status (0008,0426) to "CANCELED". Some Study records may be only partially complete at the time of the Cancel request, e.g., not all the subsidiary Series and Instance records had been compiled. Whether such partial Study records are completed and included in the Inventory SOP Instance is implementation specific. Partial Study records shall not be included in an Inventory.

If the SCP conveys a Success status for Action Type "Pause" (Action Type ID = 14), it shall pause production of the Inventory associated with the Transaction UID (0008,1195). The SCP may complete any processing necessary to reach a stable state for pausing the Inventory production to allow efficient resumption.

If the SCP conveys a Success status for Action Type "Resume" (Action Type ID = 15), it shall resume production of the Inventory associated with the Transaction UID (0008,1195).