DICOM PS3.4 2019b - Service Class Specifications

J.3.2 Operations

The DICOM AEs that claim conformance to this SOP Class as an SCU shall invoke the N-ACTION operation. The DICOM AEs that claim conformance to this SOP Class as an SCP shall support the N-ACTION operation.

J.3.2.1 Storage Commitment Request

The Storage Commitment Request operation allows an SCU to request an SCP to commit to the safekeeping of a set of SOP Instances. This operation shall be invoked through the N-ACTION primitive.

J.3.2.1.1 Action Information

The DICOM AEs that claim conformance to this SOP Class as an SCU and/or an SCP shall support the Action Types and Action Information as specified in Table J.3-1.

Table J.3-1. Storage Commitment Request - Action Information

Action Type Name

Action Type ID

Attribute Name

Tag

Requirement Type SCU/SCP

Request Storage Commitment

1

Transaction UID

(0008,1195)

1/1

Storage Media File-Set ID

(0088,0130)

3/3

See Section J.3.2.1.1.1.

Storage Media File-Set UID

(0088,0140)

3/3

See Section J.3.2.1.1.1.

Referenced SOP Sequence

(0008,1199)

1/1

>Referenced SOP Class UID

(0008,1150)

1/1

>Referenced SOP Instance UID

(0008,1155)

1/1

See Section J.3.2.1.1.3.

>Storage Media File-Set ID

(0088,0130)

3/3

See Section J.3.2.1.1.1.

>Storage Media File-Set UID

(0088,0140)

3/3

See Section J.3.2.1.1.1.


J.3.2.1.1.1 Storage Media File Set ID Attributes

If present, the Storage Media File-Set ID (0088,0130) and Storage Media File-Set UID (0088,0140) shall appear either outside the Referenced SOP Sequence (0008,1199), or within one or more Items within that sequence, but not both. If they appear outside of the sequence, then all of the SOP Instances within the sequence shall be retrievable from the specified Storage Media File-Set. If they appear within an Item of that sequence, then the SOP Instance referenced to by that Item shall be retrievable from the specified Storage Media File-Set.

J.3.2.1.1.2 Referenced Performed Procedure Step Sequence Attribute (Retired)

Referenced Performed Procedure Step Sequence (0008,1111) was included in earlier versions, but its use here has been retired. See PS 3.4-2001, in which the Attribute was formerly known as Referenced Study Component Sequence.

Note

This section formerly specified a means of referencing a Study Component that has been completed and semantics that the list of images in the commitment request represented a complete set. This section has been retired since the Modality Performed Procedure Step SOP Classes provide the same facility in a more appropriate service.

J.3.2.1.1.3 SOP Instance Reference

A SOP Instance may be referenced only once within the Referenced SOP Sequence (0008,1199).

J.3.2.1.2 Service Class User Behavior

The SCU shall use the N-ACTION primitive to request the SCP the safekeeping of a set of SOP Instances. The SOP Instances are referenced in the Action Information as specified in Table J.3-1. The Action Type ID shall be set to 1 specifying the request for storage commitment.

The SCU shall supply the Transaction UID Attribute (0008,1195) to uniquely identify each Storage Commitment Request. The value of the Transaction UID Attribute will be included by the SCP in the Storage Commitment Result (see Section J.3.3.1). Use of the Transaction UID Attribute allows the SCU to match requests and results that may occur over the same or different Associations.

The N-ACTION primitive shall contain the well-known Storage Commitment Push Model SOP Instance UID (defined in Section J.3.5) in its Requested SOP Instance UID parameter.

Note

In the usage described here, there is no explicit creation of a SOP Instance upon which an N-ACTION primitive may operate. Instead, the N-ACTION primitive operates upon a constant well-known SOP Instance. This SOP Instance is conceptually created during start up of each Storage Commitment Service Class SCP Application.

Upon receipt of a successful N-ACTION Response Status Code from the SCP, the SCU now knows that the SCP has received the N-ACTION request. Upon receipt of any other N-ACTION Response Status Code from the SCP, the SCU now knows that the SCP will not process the request and therefore will not commit to the storage of the SOP Instances referenced by the Storage Commitment Request. The actions taken by the SCU upon receiving the status is beyond the scope of this Standard. Upon receipt of a failure status, the Transaction UID is no longer active and shall not be reused for other transactions.

At any time after receipt of the N-ACTION-Response, the SCU may release the association on which it sent the N-ACTION-Request.

Note

  1. Failure of storage commitment will be signaled via the N-EVENT-REPORT primitive.

  2. In situations where the SOP Instance(s) are transferred via Media Interchange, the Storage Commitment Request may fail because the piece of Media containing the referenced SOP Instance(s) may not yet have been read. Attributes (0088,0130) File-Set ID and (0088,0140) File-Set UID may or may not be present in the case of Media Interchange. They may be provided to facilitate identification of the media containing the transferred SOP Instance(s) by the Storage Commitment SCP.

J.3.2.1.3 Service Class Provider Behavior

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. A success status conveys that the SCP has successfully received the request. A failure status conveys that the SCP is not processing the request.

Note

  1. Failure of storage commitment will be signaled via the N-EVENT-REPORT primitive.

  2. When a Storage Commitment Request is received by an SCP it may immediately assess the list of references for which Storage Commitment is requested and return an N-EVENT-REPORT. In situations where the SOP Instance(s) are transferred via Media Interchange, the N-EVENT-REPORT may fail because the piece of Media containing the referenced SOP Instance(s) may not yet have been read. Attributes (0088,0130) File-Set ID and (0088,0140) File-Set UID may or may not be present in the case of Media Interchange. They may be used to facilitate identification of the media containing the transferred SOP Instance(s) by the Storage Commitment SCP.

J.3.2.1.4 Status Codes

No Service Class specific status values are defined for the N-ACTION Service. See PS3.7 for general response status codes.

DICOM PS3.4 2019b - Service Class Specifications