D.4 Networking
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## D.4 Networking

### D.4.1 Implementation Model

#### D.4.1.1 Application Data Flow

Figure D.4.1-1. Implementation Model

The application is a single pure Java application that provides both a user interface, internal database and network listener that spawns additional threads as necessary to handle incoming connections, as well as media support.

Conceptually the network services may be modeled as the following separate AEs, though in fact all the AEs share a single (configurable) AE Title:

- ECHO-SCP, which responds to verification requests

- STORAGE-SCP, which receives incoming images and other composite instances

- STORAGE-SCU, which sends outbound images and other composite instances

- FIND-SCU, which queries remote AEs for lists of studies, series and instances

- MOVE-SCU, which retrieves selected studies, series or instances

#### D.4.1.2 Functional Definitions of AEs

##### D.4.1.2.1 ECHO-SCP

ECHO-SCP waits in the background for connections, will accept associations with Presentation Contexts for SOP Class of the Verification Service Class, and will respond successfully to echo requests.

##### D.4.1.2.2 STORAGE-SCP

STORAGE-SCP waits in the background for connections, will accept associations with Presentation Contexts for SOP Classes of the Storage Service Class, and will store the received instances to the local database where they may subsequently be listed and viewed through the user interface.

##### D.4.1.2.3 STORAGE-SCU

STORAGE-SCU is activated through the user interface when a user selects instances from the local database or a DICOMDIR, or the currently displayed instance, and requests that they be sent to a remote AE (selected from a pre-configured list).

##### D.4.1.2.4 FIND-SCU

FIND-SCU is activated through the user interface when a user selects a remote AE to query (from a pre-configured list), then initiates a query. Queries are performed recursively from the study through the series and instance levels until all matching instances have been listed.

##### D.4.1.2.5 MOVE-SCU

MOVE-SCU is activated through the user interface when a user selects a study, series or instance for retrieval. A connection to the remote AE is established to initiate and monitor the retrieval and the STORAGE-SCP AE receives the retrieved instances.

#### D.4.1.3 Sequencing of Real-World Activities

All SCP activities are performed asynchronously in the background and not dependent on any sequencing.

All SCU activities are sequentially initiated in the user interface, and another activity may not be initiated until the prior activity has completed.

### D.4.2 AE Specifications

#### D.4.2.1 ECHO-SCP

##### D.4.2.1.1 SOP Classes

ECHO-SCP provide Standard Conformance to the following SOP Class(es) :

Table D.4.2-1. SOP Classes Supported By ECHO-SCP

SOP Class Name | SOP Class UID | SCU | SCP
--- | --- | --- | ---
Verification SOP Class | 1.2.840.10008.1.1 | No | Yes

##### D.4.2.1.2 Association Policies

###### D.4.2.1.2.1 General

ECHO-SCP accepts but never initiates associations.

Table D.4.2-2. Maximum PDU Size Received as a SCP for ECHO-SCP

Maximum PDU size received | Unlimited

###### D.4.2.1.2.2 Number of Associations

Table D.4.2-3. Number of Associations as a SCP for ECHO-SCP

Maximum number of simultaneous associations | Unlimited

###### D.4.2.1.2.3 Asynchronous Nature

ECHO-SCP will only allow a single outstanding operation on an Association. Therefore, ECHO-SCP will not perform asynchronous operations window negotiation.

###### D.4.2.1.2.4 Implementation Identifying Information

Table D.4.2-4. DICOM Implementation Class and Version for ECHO-SCP

Implementation Class UID | xxxxxxxxxxx.yy.etc.ad.inf.usw
Implementation Version Name | Viewer1.0

##### D.4.2.1.3 Association Initiation Policy

ECHO-SCP does not initiate associations.

##### D.4.2.1.4 Association Acceptance Policy

When ECHO-SCP accepts an association, it will respond to echo requests. If the Called AE Title does not match the pre-configured AE Title shared by all the SCPs of the application, the association will be rejected.

###### D.4.2.1.4.1 Activity- Receive Echo Request

###### D.4.2.1.4.1.1 Description and Sequencing of Activities

###### D.4.2.1.4.1.2 Accepted Presentation Contexts

Table D.4.2-5. Acceptable Presentation Contexts for ECHO-SCP and Receive Echo Request

Presentation Context Table
Abstract Syntax | Transfer Syntax | Role | Extended Negotiation
--- | --- | --- | ---
Name | UID | Name List | UID List
Verification | 1.2.840.10008.1.1 | Implicit VR Little Endian | 1.2.840.10008.1.2 | SCP | None
Explicit VR Little Endian | 1.2.840.10008.1.2.1
Explicit VR Big Endian | 1.2.840.10008.1.2.2

###### D.4.2.1.4.1.2.1 Extended Negotiation

No extended negotiation is performed.

###### D.4.2.1.4.1.3 SOP Specific Conformance

###### D.4.2.1.4.1.3.1 SOP Specific Conformance to Verification SOP Class

ECHO-SCP provides standard conformance to the Verification Service Class.

###### D.4.2.1.4.1.3.2 Presentation Context Acceptance Criterion

ECHO-SCP will always accept any Presentation Context for the supported SOP Classes with the supported Transfer Syntaxes. More than one proposed Presentation Context will be accepted for the same Abstract Syntax if the Transfer Syntax is supported, whether or not it is the same as another Presentation Context.

###### D.4.2.1.4.1.3.3 Transfer Syntax Selection Policies

ECHO-SCP prefers explicit Transfer Syntaxes. If offered a choice of Transfer Syntaxes in a Presentation Context, it will apply the following priority to the choice of Transfer Syntax:

1. first encountered explicit Transfer Syntax,

2. default Transfer Syntax.

ECHO-SCP will accept duplicate Presentation Contexts, that is, if it is offered multiple Presentation Contexts, each of which offers acceptable Transfer Syntaxes, it will accept all Presentation Contexts, applying the same priority for selecting a Transfer Syntax for each.

#### D.4.2.2 STORAGE-SCP

##### D.4.2.2.1 SOP Classes

STORAGE-SCP provide Standard Conformance to the following SOP Class(es) :

Table D.4.2-6. SOP Classes Supported By STORAGE-SCP

SOP Class Name | SOP Class UID | SCU | SCP
--- | --- | --- | ---
Stored Print Storage | 1.2.840.10008.5.1.1.27 | No | Yes
Hardcopy Grayscale Image Storage | 1.2.840.10008.5.1.1.29 | No | Yes
Hardcopy Color Image Storage | 1.2.840.10008.5.1.1.30 | No | Yes
Computed Radiography Image Storage | 1.2.840.10008.5.1.4.1.1.1 | No | Yes
Digital X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.1 | No | Yes
Digital X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.1.1 | No | Yes
Digital Mammography X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.2 | No | Yes
Digital Mammography X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.2.1 | No | Yes
Digital Intra-oral X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.3 | No | Yes
Digital Intra-oral X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.3.1 | No | Yes
CT Image Storage | 1.2.840.10008.5.1.4.1.1.2 | No | Yes
Ultrasound Multi-frame Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.3 | No | Yes
Ultrasound Multi-frame Image Storage | 1.2.840.10008.5.1.4.1.1.3.1 | No | Yes
MR Image Storage | 1.2.840.10008.5.1.4.1.1.4 | No | Yes
Enhanced MR Image Storage | 1.2.840.10008.5.1.4.1.1.4.1 | No | Yes
MR Spectroscopy Storage | 1.2.840.10008.5.1.4.1.1.4.2 | No | Yes
Standalone Modality LUT Storage | 1.2.840.10008.5.1.4.1.1.10 | No | Yes
Standalone VOI LUT Storage | 1.2.840.10008.5.1.4.1.1.11 | No | Yes
Grayscale Softcopy Presentation State Storage | 1.2.840.10008.5.1.4.1.1.11.1 | No | Yes
X-Ray Angiographic Image Storage | 1.2.840.10008.5.1.4.1.1.12.1 | No | Yes
X-Ray Radiofluoroscopic Image Storage | 1.2.840.10008.5.1.4.1.1.12.2 | No | Yes
X-Ray Angiographic Bi-Plane Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.12.3 | No | Yes
Nuclear Medicine Image Storage | 1.2.840.10008.5.1.4.1.1.20 | No | Yes
Raw Data Storage | 1.2.840.10008.5.1.4.1.1.66 | No | Yes
VL Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.77.1 | No | Yes
VL Multi-frame Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.77.2 | No | Yes
VL Endoscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.1 | No | Yes
VL Microscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.2 | No | Yes
VL Slide-Coordinates Microscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.3 | No | Yes
VL Photographic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.4 | No | Yes
Basic Text SR | 1.2.840.10008.5.1.4.1.1.88.11 | No | Yes
Enhanced SR | 1.2.840.10008.5.1.4.1.1.88.22 | No | Yes
Comprehensive SR | 1.2.840.10008.5.1.4.1.1.88.33 | No | Yes
Mammography CAD SR | 1.2.840.10008.5.1.4.1.1.88.50 | No | Yes
Key Object Selection Document | 1.2.840.10008.5.1.4.1.1.88.59 | No | Yes
Positron Emission Tomography Image Storage | 1.2.840.10008.5.1.4.1.1.128 | No | Yes
Standalone PET Curve Storage | 1.2.840.10008.5.1.4.1.1.129 | No | Yes
RT Image Storage | 1.2.840.10008.5.1.4.1.1.481.1 | No | Yes
RT Dose Storage | 1.2.840.10008.5.1.4.1.1.481.2 | No | Yes
RT Structure Set Storage | 1.2.840.10008.5.1.4.1.1.481.3 | No | Yes
RT Beams Treatment Record Storage | 1.2.840.10008.5.1.4.1.1.481.4 | No | Yes
RT Plan Storage | 1.2.840.10008.5.1.4.1.1.481.5 | No | Yes
RT Brachy Treatment Record Storage | 1.2.840.10008.5.1.4.1.1.481.6 | No | Yes
RT Treatment Summary Record Storage | 1.2.840.10008.5.1.4.1.1.481.7 | No | Yes

##### D.4.2.2.2 Association Policies

###### D.4.2.2.2.1 General

STORAGE-SCP accepts but never initiates associations.

Table D.4.2-7. Maximum PDU Size Received as a SCP for STORAGE-SCP

Maximum PDU size received | Unlimited

###### D.4.2.2.2.2 Number of Associations

Table D.4.2-8. Number of Associations as a SCP for STORAGE-SCP

Maximum number of simultaneous associations | Unlimited

###### D.4.2.2.2.3 Asynchronous Nature

STORAGE-SCP will only allow a single outstanding operation on an Association. Therefore, STORAGE-SCP will not perform asynchronous operations window negotiation.

###### D.4.2.2.2.4 Implementation Identifying Information

Table D.4.2-9. DICOM Implementation Class and Version for STORAGE-SCP

Implementation Class UID | xxxxxxxxxxx.yy.etc.ad.inf.usw
Implementation Version Name | Viewer1.0

##### D.4.2.2.3 Association Initiation Policy

STORAGE-SCP does not initiate associations.

##### D.4.2.2.4 Association Acceptance Policy

When STORAGE-SCP accepts an association, it will respond to storage requests. If the Called AE Title does not match the pre-configured AE Title shared by all the SCPs of the application, the association will be rejected.

###### D.4.2.2.4.1 Activity - Receive Storage Request

###### D.4.2.2.4.1.1 Description and Sequencing of Activities

As instances are received they are copied to the local file system and a record inserted into the local database. If the received instance is a duplicate of a previously received instance, the old file and database record will be overwritten with the new one.

###### D.4.2.2.4.1.2 Accepted Presentation Contexts

Table D.4.2-10. Acceptable Presentation Contexts for STORAGE-SCP and Receive Storage Request

Presentation Context Table
Abstract Syntax | Transfer Syntax | Role | Extended Negotiation
--- | --- | --- | ---
Name | UID | Name List | UID List
See Table D.4.2-6 | See Table D.4.2-6 | Implicit VR Little Endian | 1.2.840.10008.1.2 | SCP | None
Explicit VR Little Endian | 1.2.840.10008.1.2.1
Explicit VR Big Endian | 1.2.840.10008.1.2.2

###### D.4.2.2.4.1.2.1 Extended Negotiation

No extended negotiation is performed, though STORAGE-SCP:

- is a Level 2 Storage SCP (Full - does not discard any data elements)

- does not support digital signatures

- does not coerce any received data elements

###### D.4.2.2.4.1.3 SOP Specific Conformance

###### D.4.2.2.4.1.3.1 SOP Specific Conformance to Storage SOP Classes

STORAGE-SCP provides standard conformance to the Storage Service Class.

When displaying an image in the viewing application, the newest Grayscale Softcopy Presentation State containing references to the image will be automatically applied and the GSPS Presentation Label and Presentation description will be displayed. The user has the option to select any other Presentation States that also references the image. If no Presentation State references the image then no Presentation State will be applied by default.

The Mask Subtraction transformation is not supported by this implementation. It is not possible display Presentation States containing the Mask Subtraction Sequence (0028,6100).

All of the Image Storage SOP Classes listed in Table D.4.2-6 are supported as references from instances of the Grayscale Softcopy Presentation State Storage SOP Class.

###### D.4.2.2.4.1.3.2 Presentation Context Acceptance Criterion

STORAGE-SCP will always accept any Presentation Context for the supported SOP Classes with the supported Transfer Syntaxes. More than one proposed Presentation Context will be accepted for the same Abstract Syntax if the Transfer Syntax is supported, whether or not it is the same as another Presentation Context.

###### D.4.2.2.4.1.3.3 Transfer Syntax Selection Policies

STORAGE-SCP prefers explicit Transfer Syntaxes. If offered a choice of Transfer Syntaxes in a Presentation Context, it will apply the following priority to the choice of Transfer Syntax:

1. first encountered explicit Transfer Syntax,

2. default Transfer Syntax.

STORAGE-SCP will accept duplicate Presentation Contexts, that is, if it is offered multiple Presentation Contexts, each of which offers acceptable Transfer Syntaxes, it will accept all Presentation Contexts, applying the same priority for selecting a Transfer Syntax for each.

###### D.4.2.2.4.1.3.4 Response Status

STORAGE-SCP will behave as described in the Table below when generating the C-STORE response command message.

Table D.4.2-11. Response Status for STORAGE-SCP and Receive Storage Request

Service Status | Further Meaning | Status Codes | Reason
--- | --- | --- | ---
Refused | Out of Resources | A7xx | Never sent
Error | Data Set does not match SOP Class | A9xx | Never sent - data set is not checked prior to storage
| Cannot understand | Cxxx | Never sent
Warning | Coercion of Data Elements | B000 | Never sent - no coercion is ever performed
| Data Set does not match SOP Class | B007 | Never sent - data set is not checked prior to storage
| Elements Discarded | B006 | Never sent - all elements are always stored
Success |  | 0000 |

#### D.4.2.3 STORAGE-SCU

##### D.4.2.3.1 SOP Classes

STORAGE-SCU provide Standard Conformance to the following SOP Class(es) :

Table D.4.2-12. SOP Classes Supported By STORAGE-SCU

SOP Class Name | SOP Class UID | SCU | SCP
--- | --- | --- | ---
Stored Print Storage | 1.2.840.10008.5.1.1.27 | Yes | No
Hardcopy Grayscale Image Storage | 1.2.840.10008.5.1.1.29 | Yes | No
Hardcopy Color Image Storage | 1.2.840.10008.5.1.1.30 | Yes | No
Computed Radiography Image Storage | 1.2.840.10008.5.1.4.1.1.1 | Yes | No
Digital X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.1 | Yes | No
Digital X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.1.1 | Yes | No
Digital Mammography X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.2 | Yes | No
Digital Mammography X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.2.1 | Yes | No
Digital Intra-oral X-Ray Image Storage - For Presentation | 1.2.840.10008.5.1.4.1.1.1.3 | Yes | No
Digital Intra-oral X-Ray Image Storage - For Processing | 1.2.840.10008.5.1.4.1.1.1.3.1 | Yes | No
CT Image Storage | 1.2.840.10008.5.1.4.1.1.2 | Yes | No
Ultrasound Multi-frame Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.3 | Yes | No
Ultrasound Multi-frame Image Storage | 1.2.840.10008.5.1.4.1.1.3.1 | Yes | No
MR Image Storage | 1.2.840.10008.5.1.4.1.1.4 | Yes | No
Enhanced MR Image Storage | 1.2.840.10008.5.1.4.1.1.4.1 | Yes | No
MR Spectroscopy Storage | 1.2.840.10008.5.1.4.1.1.4.2 | Yes | No
Standalone Modality LUT Storage | 1.2.840.10008.5.1.4.1.1.10 | Yes | No
Standalone VOI LUT Storage | 1.2.840.10008.5.1.4.1.1.11 | Yes | No
Grayscale Softcopy Presentation State Storage | 1.2.840.10008.5.1.4.1.1.11.1 | Yes | No
X-Ray Angiographic Image Storage | 1.2.840.10008.5.1.4.1.1.12.1 | Yes | No
X-Ray Radiofluoroscopic Image Storage | 1.2.840.10008.5.1.4.1.1.12.2 | Yes | No
X-Ray Angiographic Bi-Plane Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.12.3 | Yes | No
Nuclear Medicine Image Storage | 1.2.840.10008.5.1.4.1.1.20 | Yes | No
Raw Data Storage | 1.2.840.10008.5.1.4.1.1.66 | Yes | No
VL Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.77.1 | Yes | No
VL Multi-frame Image Storage (Retired) | 1.2.840.10008.5.1.4.1.1.77.2 | Yes | No
VL Endoscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.1 | Yes | No
VL Microscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.2 | Yes | No
VL Slide-Coordinates Microscopic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.3 | Yes | No
VL Photographic Image Storage | 1.2.840.10008.5.1.4.1.1.77.1.4 | Yes | No
Basic Text SR | 1.2.840.10008.5.1.4.1.1.88.11 | Yes | No
Enhanced SR | 1.2.840.10008.5.1.4.1.1.88.22 | Yes | No
Comprehensive SR | 1.2.840.10008.5.1.4.1.1.88.33 | Yes | No
Mammography CAD SR | 1.2.840.10008.5.1.4.1.1.88.50 | Yes | No
Key Object Selection Document | 1.2.840.10008.5.1.4.1.1.88.59 | Yes | No
Positron Emission Tomography Image Storage | 1.2.840.10008.5.1.4.1.1.128 | Yes | No
Standalone PET Curve Storage | 1.2.840.10008.5.1.4.1.1.129 | Yes | No
RT Image Storage | 1.2.840.10008.5.1.4.1.1.481.1 | Yes | No
RT Dose Storage | 1.2.840.10008.5.1.4.1.1.481.2 | Yes | No
RT Structure Set Storage | 1.2.840.10008.5.1.4.1.1.481.3 | Yes | No
RT Beams Treatment Record Storage | 1.2.840.10008.5.1.4.1.1.481.4 | Yes | No
RT Plan Storage | 1.2.840.10008.5.1.4.1.1.481.5 | Yes | No
RT Brachy Treatment Record Storage | 1.2.840.10008.5.1.4.1.1.481.6 | Yes | No
RT Treatment Summary Record Storage | 1.2.840.10008.5.1.4.1.1.481.7 | Yes | No

##### D.4.2.3.2 Association Policies

###### D.4.2.3.2.1 General

STORAGE-SCU initiates but never accepts associations.

Table D.4.2-13. Maximum PDU Size Received as a SCP for STORAGE-SCU

Maximum PDU size received | Unlimited

###### D.4.2.3.2.2 Number of Associations

Table D.4.2-14. Number of Associations as a SCP for STORAGE-SCU

Maximum number of simultaneous associations | 1

###### D.4.2.3.2.3 Asynchronous Nature

STORAGE-SCU will only allow a single outstanding operation on an Association. Therefore, STORAGE-SCU will not perform asynchronous operations window negotiation.

###### D.4.2.3.2.4 Implementation Identifying Information

Table D.4.2-15. DICOM Implementation Class and Version for STORAGE-SCU

Implementation Class UID | xxxxxxxxxxx.yy.etc.ad.inf.usw
Implementation Version Name | Viewer1.0

##### D.4.2.3.3 Association Initiation Policy

STORAGE-SCU attempts to initiate a new association for each instance it attempts to transfer.

###### D.4.2.3.3.1 Activity - Send Storage Request

###### D.4.2.3.3.1.1 Description and Sequencing of Activities

For each instance selected from the user interface to be transferred, a single attempt will be made to transmit it to the selected remote AE. If the send fails, for whatever reason, no retry will be performed, and an attempt will be made to send the next instance.

###### D.4.2.3.3.1.2 Proposed Presentation Contexts

Table D.4.2-16. Proposed Presentation Contexts for STORAGE-SCU and Receive Storage Request

Presentation Context Table
Abstract Syntax | Transfer Syntax | Role | Extended Negotiation
--- | --- | --- | ---
Name | UID | Name List | UID List
See Table D.4.2-12 | See Table D.4.2-12 | Implicit VR Little Endian | 1.2.840.10008.1.2 | SCU | None
Explicit VR Little Endian | 1.2.840.10008.1.2.1
Explicit VR Big Endian | 1.2.840.10008.1.2.2

STORAGE-SCU will propose Presentation Contexts only for the SOP Class of the instance that is to be transferred.

For that SOP Class, STORAGE-SCU will propose multiple Presentation Contexts, one for each of the supported Transfer Syntaxes, and an additional Presentation Context with all of the supported Transfer Syntaxes, in order to determine which Transfer Syntaxes the remote SCP supports, and which it prefers.

###### D.4.2.3.3.1.2.1 Extended Negotiation

No extended negotiation is performed.

###### D.4.2.3.3.1.3 SOP Specific Conformance

###### D.4.2.3.3.1.3.1 SOP Specific Conformance to Storage SOP Classes

STORAGE-SCU provides standard conformance to the Storage Service Class.

###### D.4.2.3.3.1.3.2 Presentation Context Acceptance Criterion

STORAGE-SCU does not accept associations.

###### D.4.2.3.3.1.3.3 Transfer Syntax Selection Policies

STORAGE-SCU prefers explicit Transfer Syntaxes. If offered a choice of Transfer Syntaxes in the accepted Presentation Contexts, it will apply the following priority to the choice of Presentation Context to use for the C-STORE operation:

1. first encountered explicit Transfer Syntax,

2. default Transfer Syntax.

###### D.4.2.3.3.1.3.4 Response Status

STORAGE-SCU will behave as described in the Table below in response to the status returned in the C-STORE response command message.

Table D.4.2-17. Response Status for STORAGE-SCU and Receive Storage Request

Service Status | Further Meaning | Status Codes | Behavior
--- | --- | --- | ---
Refused | Out of Resources | A7xx | Ignored
Error | Data Set does not match SOP Class | A9xx | Ignored
| Cannot understand | Cxxx | Ignored
Warning | Coercion of Data Elements | B000 | Ignored
| Data Set does not match SOP Class | B007 | Ignored
| Elements Discarded | B006 | Ignored
Success |  | 0000 | Ignored

##### D.4.2.3.4 Association Acceptance Policy

STORAGE-SCU does not accept associations.

#### D.4.2.4 FIND-SCU

##### D.4.2.4.1 SOP Classes

FIND-SCU provide Standard Conformance to the following SOP Class(es) :

Table D.4.2-18. SOP Classes Supported By FIND-SCU

SOP Class Name | SOP Class UID | SCU | SCP
--- | --- | --- | ---
Study Root Query/Retrieve Information Model - FIND | 1.2.840.10008.5.1.4.1.2.2.1 | Yes | No

##### D.4.2.4.2 Association Policies

###### D.4.2.4.2.1 General

FIND-SCU initiates but never accepts associations.

Table D.4.2-19. Maximum PDU Size Received as a SCP for FIND-SCU

Maximum PDU size received | Unlimited

###### D.4.2.4.2.2 Number of Associations

Table D.4.2-20. Number of Associations as a SCP for FIND-SCU

Maximum number of simultaneous associations | 1

###### D.4.2.4.2.3 Asynchronous Nature

FIND-SCU will only allow a single outstanding operation on an Association. Therefore, FIND-SCU will not perform asynchronous operations window negotiation.

###### D.4.2.4.2.4 Implementation Identifying Information

Table D.4.2-21. DICOM Implementation Class and Version for FIND-SCU

Implementation Class UID | xxxxxxxxxxx.yy.etc.ad.inf.usw
Implementation Version Name | Viewer1.0

##### D.4.2.4.3 Association Initiation Policy

FIND-SCU attempts to initiate a new association when the user performs the query action from the user interface. If this involves recursive queries for lower query levels in the hierarchy, these will be performed on the same association.

###### D.4.2.4.3.1 Activity - Query Remote AE

###### D.4.2.4.3.1.1 Description and Sequencing of Activities

A single attempt will be made to query the remote AE. If the query fails, for whatever reason, no retry will be performed.

###### D.4.2.4.3.1.2 Proposed Presentation Contexts

Table D.4.2-22. Proposed Presentation Contexts for FIND-SCU and Query Remote AE

Presentation Context Table
Abstract Syntax | Transfer Syntax | Role | Extended Negotiation
--- | --- | --- | ---
Name | UID | Name | UID
See Table D.4.2-18 | See Table D.4.2-18 | Implicit VR Little Endian | 1.2.840.10008.1.2 | SCU | None
Explicit VR Little Endian | 1.2.840.10008.1.2.1
Explicit VR Big Endian | 1.2.840.10008.1.2.2

FIND-SCU will propose multiple Presentation Contexts, one for each of the supported Transfer Syntaxes, and an additional Presentation Context with all of the supported Transfer Syntaxes, in order to determine which Transfer Syntaxes the remote SCP supports, and which it prefers.

###### D.4.2.4.3.1.2.1 Extended Negotiation

No extended negotiation is performed.

In particular, relational queries are not supported.

###### D.4.2.4.3.1.3 SOP Specific Conformance

###### D.4.2.4.3.1.3.1 SOP Specific Conformance to C-FIND SOP Classes

FIND-SCU provides standard conformance to the supported C-FIND SOP Classes.

Only a single information model, Study Root, is supported.

All queries are initiated at the highest level of the information model (the STUDY level), and then for each response received, recursively repeated at the next lower levels (the SERIES and then IMAGE levels), in order to completely elucidate the "tree" of instances available on the remote AE (from which the user may subsequently request a retrieval at any level).

No CANCEL requests are ever issued.

Unexpected attributes returned in a C-FIND response (those not requested) are listed in the browser at the appropriate level if present in the dictionary. Requested return attributes not returned by the SCP are ignored. Non-matching responses returned by the SCP due to unsupported (hopefully optional) matching keys are not filtered locally by the FIND-SCU and thus will still be presented in the browser. No attempt is made to filter out duplicate responses.

Specific Character Set will always be included at every query level. If present in the response, Specific Character Set will be used to identify character sets other than the default character set for display of strings in the browser.

Table D.4.2-23. Study Root Request Identifier for FIND-SCU

Name | Tag | Types of Matching
--- | --- | ---
STUDY Level |  |
Patient's ID | (0010,0020) | S,*,U
Patient's Name | (0010,0010) | S,*,U
Patient's Birth Date | (0010,0030) | S,*,U,R
Patient's Sex | (0010,0040) | S,*,U
Patient's Birth Time | (0010,0032) | S,*,U,R
Other Patient's ID's | (0010,1000) | S,*,U
Other Patient's Names | (0010,1001) | S,*,U
Ethnic Group | (0010,2160) | S,*,U
Patient Comments | (0010,4000) | S,*,U
Study ID | (0020,0010) | S,*,U
Study Description | (0008,1030) | S,*,U
Modalities In Study | (0008,0061) | S,*,U
Study Date | (0008,0020) | S,*,U,R
Study Time | (0008,0030) | S,*,U,R
Referring Physician's Name | (0008,0090) | S,*,U
Accession Number | (0008,0050) | S,*,U
Physician of Record | (0008,1048) | S,*,U
Name of Physician(s) Reading Study | (0008,1060) | S,*,U
Admitting Diagnoses Description | (0008,1080) | S,*,U
Patient's Age | (0010,1010) | S,*,U
Patient's Size | (0010,1020) | S,*,U
Patient's Weight | (0010,1030) | S,*,U
Occupation | (0010,2180) | S,*,U
Additional Patient History | (0010,21B0) | S,*,U
Study Instance UID | (0020,000D) | UNIQUE
SERIES Level |  |
Series Number | (0020,0011) | S,*,U
Series Description | (0008,103E) | S,*,U
Modality | (0008,0060) | S,*,U
Series Date | (0008,0021) | S,*,U
Series Time | (0008,0031) | S,*,U
Performing Physician's Name | (0008,1050) | S,*,U
Protocol Name | (0018,1030) | S,*,U
Operator's Name | (0008,1070) | S,*,U
Laterality | (0020,0060) | S,*,U
Body Part Examined | (0018,0015) | S,*,U
Manufacturer | (0008,0070) | S,*,U
Manufacturer's Model Name | (0008,1090) | S,*,U
Station Name | (0008,1010) | S,*,U
Institution Name | (0008,0080) | S,*,U
Institutional Department Name | (0008,1040) | S,*,U
Series Instance UID | (0020,000E) | UNIQUE
IMAGE Level |  |
Instance Number | (0020,0013) | S,*,U
Image Comments | (0020,4000) | S,*,U
Content Date | (0008,0023) | S,*,U,R
Content Time | (0008,0033) | S,*,U,R
Image Type | (0008,0008) | S,*,U
Acquisition Number | (0020,0012) | S,*,U
Acquisition Date | (0008,0022) | S,*,U,R
Acquisition Time | (0008,0032) | S,*,U,R
Acquisition Date Time | (0008,002A) | S,*,U,R
Derivation Description | (0008,2111) | S,*,U
Contrast/Bolus Agent | (0018,0010) | S,*,U
Quality Control Image | (0028,0300) | S,*,U
Burned In Annotation | (0028,0301) | S,*,U
Lossy Image Compression | (0028,2110) | S,*,U
Lossy Image Compression Ratio | (0028,2112) | S,*,U
Number of Frames | (0028,0008) | S,*,U
SOP Instance UID | (0008,0018) | UNIQUE
SOP Class UID | (0008,0016) | NONE
Common to all query levels |  |
Specific Character Set | (0008,0005) | S,*,U

Types of Matching:

The types of Matching supported by the C-FIND SCU. An "S" indicates the identifier attribute uses Single Value Matching, an "R" indicates Range Matching, a n"*"indicates wild card matching, a 'U' indicates Universal Matching, and an 'L' indicates that UID lists are sent. "NONE" indicates that no matching is supported, but that values for this Element are requested to be returned (i.e., universal matching), and "UNIQUE" indicates that this is the Unique Key for that query level, in which case Universal Matching or Single Value Matching is used depending on the query level.

###### D.4.2.4.3.1.3.2 Presentation Context Acceptance Criterion

FIND-SCU does not accept associations.

###### D.4.2.4.3.1.3.3 Transfer Syntax Selection Policies

FIND-SCU prefers explicit Transfer Syntaxes. If offered a choice of Transfer Syntaxes in the accepted Presentation Contexts, it will apply the following priority to the choice of Presentation Context to use for the C-STORE operation:

1. first encountered explicit Transfer Syntax,

2. default Transfer Syntax.

###### D.4.2.4.3.1.3.4 Response Status

FIND-SCU will behave as described in Table D.4.2-24 in response to the status returned in the C-FIND response command message(s).

Table D.4.2-24. Response Status for FIND-SCU and Query Remote AE Request

Service Status | Further Meaning | Status Codes | Behavior
--- | --- | --- | ---
Refused | Out of Resources | A700 | Current query is terminated; remaining queries continue
Error | Identifier does not match SOP Class | A900 | Current query is terminated; remaining queries continue
| Unable to process | Cxxx | Current query is terminated; remaining queries continue
Cancel | Matching terminated due to Cancel request | FE00 | Ignored (should never occur, since cancels never issued)
Success | Matching is complete - No final Identifier is supplied | 0000 | Current query is terminated; remaining queries continue
Pending | Matches are continuing - Current Match is supplied and any Optional Keys were supported in the same manner as Required Keys | FF00 | Identifier used to populate browser and trigger recursive lower level queries
| Matches are continuing - Warning that one or more Optional Keys were not supported for existence and/or matching for this Identifier | FF01 | Identifier used to populate browser and trigger recursive lower level queries

##### D.4.2.4.4 Association Acceptance Policy

FIND-SCU does not accept associations.

#### D.4.2.5 MOVE-SCU

##### D.4.2.5.1 SOP Classes

MOVE-SCU provide Standard Conformance to the following SOP Class(es) :

Table D.4.2-25. SOP Classes Supported By MOVE-SCU

SOP Class Name | SOP Class UID | SCU | SCP
--- | --- | --- | ---
Study Root Query/Retrieve Information Model - MOVE | 1.2.840.10008.5.1.4.1.2.2.2 | Yes | No

##### D.4.2.5.2 Association Policies

###### D.4.2.5.2.1 General

MOVE-SCU initiates but never accepts associations.

Table D.4.2-26. Maximum PDU Size Received as a SCP for MOVE-SCU

Maximum PDU size received | Unlimited

###### D.4.2.5.2.2 Number of Associations

Table D.4.2-27. Number of Associations as a SCP for MOVE-SCU

Maximum number of simultaneous associations | 1

###### D.4.2.5.2.3 Asynchronous Nature

MOVE-SCU will only allow a single outstanding operation on an Association. Therefore, MOVE-SCU will not perform asynchronous operations window negotiation.

###### D.4.2.5.2.4 Implementation Identifying Information

Table D.4.2-28. DICOM Implementation Class and Version for MOVE-SCU

Implementation Class UID | xxxxxxxxxxx.yy.etc.ad.inf.usw
Implementation Version Name | Viewer1.0

##### D.4.2.5.3 Association Initiation Policy

MOVE-SCU attempts to initiate a new association when the user performs the retrieve action from the user interface.

###### D.4.2.5.3.1 Activity - Retrieve From Remote AE

###### D.4.2.5.3.1.1 Description and Sequencing of Activities

For the entity (study, series or instance) selected from the user interface to be retrieved, a single attempt will be made to retrieve it from the selected remote AE. If the retrieve fails, for whatever reason, no retry will be performed.

###### D.4.2.5.3.1.2 Proposed Presentation Contexts

Table D.4.2-29. Proposed Presentation Contexts for MOVE-SCU and Retrieve From Remote AE

Presentation Context Table
Abstract Syntax | Transfer Syntax | Role | Extended Negotiation
--- | --- | --- | ---
Name | UID | Name List | UID List
See Table D.4.2-25 | See Table D.4.2-25 | Implicit VR Little Endian | 1.2.840.10008.1.2 | SCP | None
Explicit VR Little Endian | 1.2.840.10008.1.2.1
Explicit VR Big Endian | 1.2.840.10008.1.2.2

MOVE-SCU will propose multiple Presentation Contexts, one for each of the supported Transfer Syntaxes, and an additional Presentation Context with all of the supported Transfer Syntaxes, in order to determine which Transfer Syntaxes the remote SCP supports, and which it prefers.

###### D.4.2.5.3.1.2.1 Extended Negotiation

No extended negotiation is performed.

In particular, relational retrievals are not supported.

###### D.4.2.5.3.1.3 SOP Specific Conformance

###### D.4.2.5.3.1.3.1 SOP Specific Conformance to C-FIND SOP Classes

MOVE-SCU provides standard conformance to the supported C-MOVE SOP Classes.

Only a single information model, Study Root, is supported.

A retrieval will be performed at the STUDY, SERIES or IMAGE level depending on what level of entity has been selected by the user in the browser.

No CANCEL requests are ever issued.

The retrieval is performed from the AE that was specified in the Retrieve AE attribute returned from the query performed by FIND-SCU. The instances are retrieved to the current application's local database by specifying the destination as the AE Title of the STORE-SCP AE of the local application. This implies that the remote C-MOVE SCP must be preconfigured to determine the presentation address corresponding to the STORE-SCP AE. The STORE-SCP AE will accept storage requests addressed to it from anywhere, so no pre-configuration of the local application to accept from the remote AE is necessary (except in so far as it was necessary to configure FIND-SCU).

Table D.4.2-30. Study Root Request Identifier for MOVE-SCU

Name | Tag | Unique, Matching or Return Key
--- | --- | ---
STUDY level
Study Instance UID | (0020,000D) | U
SERIES level
Series Instance UID | (0020,000E) | U
IMAGE level
SOP Instance UID | (0008,0018) | U

###### D.4.2.5.3.1.3.2 Presentation Context Acceptance Criterion

MOVE-SCU does not accept associations.

###### D.4.2.5.3.1.3.3 Transfer Syntax Selection Policies

MOVE-SCU prefers explicit Transfer Syntaxes. If offered a choice of Transfer Syntaxes in the accepted Presentation Contexts, it will apply the following priority to the choice of Presentation Context to use for the C-STORE operation:

1. first encountered explicit Transfer Syntax,

###### D.4.2.5.3.1.3.4 Response Status

MOVE-SCU will behave as described in the Table below in response to the status returned in the C-MOVE response command message(s).

Table D.4.2-31. Response Status for MOVE-SCU and Retrieve From Remote AE Request

Service Status | Further Meaning | Status Codes | Related Fields | Behavior
--- | --- | --- | --- | ---
Refused | Out of Resources - Unable to calculate number of matches | A701 | (0000,0902) | Retrieval is terminated
| Out of Resources - Unable to perform sub-operations | A702 | (0000,1020) (0000,1021) (0000,1022) (0000,1023) | Retrieval is terminated
| Move Destination unknown | A801 | (0000,0902) | Retrieval is terminated
Failed | Identifier does not match SOP Class | A900 | (0000,0901) (0000,0902) | Retrieval is terminated
| Unable to process | Cxxx | (0000,0901) (0000,0902) | Retrieval is terminated
Cancel | Sub-operations terminated due to Cancel Indication | FE00 | (0000,1020) (0000,1021) (0000,1022) (0000,1023) | Retrieval is terminated (should never occur, since cancels never issued)
Warning | Sub-operations Complete - One or more Failures | B000 | (0000,1020) (0000,1022) (0000,1023) | Retrieval is terminated
Success | Sub-operations Complete - No Failures | 0000 | (0000,1020) (0000,1021) (0000,1022) (0000,1023) | Retrieval is terminated
Pending | Sub-operations are continuing | FF00 | (0000,1020) (0000,1021) (0000,1022) (0000,1023) | Retrieval continues

###### D.4.2.5.3.1.3.5 Sub-Operation Dependent Behavior

Since the C-MOVE operation is dependent on completion of C-STORE sub-operations that are occurring on a separate association, the question of failure of operations on the other association(s) must be considered.

MOVE-SCU completely ignores whatever activities are taking place in relation to the STORAGE-SCP AE that is receiving the retrieved instances. Once the C-MOVE has been initiated it runs to completion (or failure) as described in the C-MOVE response command message(s). There is no attempt by MOVE-SCU to confirm that instances have actually been successfully received or locally stored.

Whether or not completely or partially successfully retrievals are made available in the local database to the user is purely dependent on the success or failure of the C-STORE sub-operations, not on any explicit action by MOVE-SCU.

Whether or not the remote AE attempts to retry any failed C-STORE sub-operations is beyond the control of MOVE-SCU.

If the association on which the C-MOVE was issued is aborted for any reason, whether or not the C-STORE sub-operations continue is dependent on the remote AE; the local STORAGE-SCP will continue to accept associations and storage operations regardless.

##### D.4.2.5.4 Association Acceptance Policy

MOVE-SCU does not accept associations.

### D.4.3 Network Interfaces

#### D.4.3.1 Physical Network Interface

The application is indifferent to the physical medium over which TCP/IP executes, which is dependent on the underlying operating system and hardware.

#### D.4.3.2 Additional Protocols

When host names rather than IP addresses are used in the configuration properties to specify presentation addresses for remote AEs, the application is dependent on the name resolution mechanism of the underlying operating system.

#### D.4.3.3 IPv4 and IPv6 Support

This product supports both IPv4 and IPv6. It does not utilize any of the optional configuration identification or security features of IPv6.

### D.4.4 Configuration

All configuration is performed through the use of Java properties file(s) stored in pre-defined locations that are specific to the underlying operating system. Refer to the Release Notes for specific details.

#### D.4.4.1 AE Title/Presentation Address Mapping

The Calling AE Title of the local application is configurable in the preferences file, and is shared by all of the AEs. The mapping of the logical name by which remote AEs are described in the user interface to Called AE Titles as well as presentation address (hostname or IP address and port number) is configurable in the preferences file.

#### D.4.4.2 Parameters

Table D.4.4-1. Configuration Parameters Table

Parameter | Configurable | Default Value
--- | --- | ---
General Parameters
PDU Size | No | 16kB
Time-out waiting for acceptance or rejection Response to an Association Open Request. (Application Level timeout) | No | None
General DIMSE level time-out values | No | None
Time-out waiting for response to TCP/IP connect() request. (Low-level timeout) | No | None
Time-out waiting for acceptance of a TCP/IP message over the network. (Low-level timeout) | No | None
Time-out for waiting for data between TCP/IP packets. (Low-level timeout) | No | None
Any changes to default TCP/IP settings, such as configurable stack parameters. | No | None
AE Specific Parameters (all AEs)
Size constraint in maximum object size | No | None
Maximum PDU size the AE can receive (see note 1) | No | Unlimited
Maximum PDU size the AE can send | No | Unlimited
AE specific DIMSE level time-out values | No | None
Number of simultaneous Associations by Service and/or SOP Class | No | Unlimited
SOP Class support | No | All supported SOP Classes always proposed and accepted
Transfer Syntax support | No | All supported Transfer Syntaxes always proposed and accepted
Other parameters that are configurable | No | None

### Note

Though the application can support unlimited PDU sizes, it will never offer a Maximum Received PDU Length of zero (unlimited) since this triggers a bug in some older systems.

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