Annex A VERIFICATION SERVICE CLASS (Normative)

A.1 Overview

A.1.1 Scope

The Verification Service Class defines a service which verifies application level communication between peer DICOM AEs. This verification is accomplished on an established Association using the C-ECHO DIMSE-C service.

A.2 SCU/SCP Behavior

A DICOM AE, supporting the Verification SOP Class SCU role, requests verification of communication to a remote DICOM AE. This request is performed using the C-ECHO request primitive. The remote DICOM AE, supporting the Verification SOP Class SCP role, issues an C-ECHO response primitive. Upon receipt of the C-ECHO confirmation, the SCU determines that verification is complete. See PS 3.7 for the specification of the C-ECHO primitives.

A.3 DIMSE-C Service Group

The C-ECHO DIMSE-C service shall be the mechanism used to verify communications between peer DICOM AEs. The C-ECHO service and protocol parameters shall be required as defined in PS 3.7.

A.4 Verification SOP class

The Verification SOP Class consists of the C-ECHO DIMSE-C service. No associated Information Object Definition is defined. The SOP Class UID shall be "1.2.840.10008.1.1".

No Specialized SOP Classes and/or Meta SOP Classes shall be defined for the Verification SOP Class.

A.5 Association negotiation

Association establishment is the first phase of any instance of communication between peer DICOM AEs. The following negotiation rules apply to DICOM AEs which support the Verification SOP Class

— The Association-requester (verification SCU role) in the A-ASSOCIATE request shall convey an Abstract Syntax, in a Presentation Context, for the Verification SOP Class. The Abstract Syntax Name shall be equivalent to the Verification SOP Class UID.

— The Association-acceptor (verification SCP role) in the A-ASSOCIATE response shall accept the Abstract Syntax, in a Presentation Context, for the supported Verification SOP Class.

No Application Association Information specific to the Verification SOP Class shall be used.

A.6 Conformance

A.6.1 Conformance supporting the SCU role

Implementations which conform to the Verification SOP Class SCU role shall meet the:

— C-ECHO service requirements as defined by the DIMSE Service Group, Section A.3

— Association negotiation rules as defined in Section A.5

A.6.2 Conformance Supporting the SCP Role

Implementations which conform to the Verification SOP Class SCP role shall meet the:

— C-ECHO operation rules as defined by the DIMSE Service Group, Section A.3

— Association negotiation rules as defined in Section A.5

A.6.3 Conformance statement

An implementation may conform to the Verification SOP Class as an SCU, SCP, or both. The Conformance Statement shall be in the format defined in PS 3.2.