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DICOM Image Communication in DICOM Image Communication in Globus-Based Medical Grids Globus-Based Medical Grids

Michal Vossberg, Thomas Tolxdorff, Associate Member, IEEE,

and Dagmar Krefting

Ting-Wei, Chen

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Outline

Introduction Related Work Methods Results and Discussion Conclusion and Future Work

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Introduction (cont.)

Grid environment (Medical grid) Secure Reliable Highly efficient data transport

Grid Middleware Globus toolkit Lack the integration the world-wide medical

image communication standard Digital Imaging and Communication in Medicine (DICOM)

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Introduction (cont.)

DICOM’s Advantage: Interoperability Asynchronous communication Integrity

From the DICOM protocol to the FTP protocol’s Disadvantage: Reduce most of the advantages and security an

integrated network of DICOM devices offers

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Introduction (cont.)

Problem Incompatible between the different imaging

devices

Solution Adapts the DICOM protocol to the Globus grid

security infrastructure

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Introduction (cont.)

Standardization Ensure compatible Correct representation

Imaging equipment of the different vendors Expect

Healthcare business The way the various healthcare actors interact

with one another

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Introduction (cont.)

Medical grid projects European Enabling Grids for E-Science in

Europe (EGEE) U.S. cancer network caBIG MediGRID

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Related Work (cont.)

Toolkit’s common security infrastructure Encryption and integrity verification of the data Authentication user or host Authorization based on the host

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Related Work (cont.)

Globus components Grid Security Interface (GSI) Grid File Transfer Protocol (Grid-FTP) Grid Services and HTTP DICOM Grid Interface Service (DGIS) Medical Data Manager (MDM) Others: Storage Resource Broker (SRB)

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Methods (cont.)

Grid-DICOM Upper layer messaging protocol for message

and data exchange Allow secure communication through an

encrypted transport protocol TLS/SSL Use a Java implementation of the DICOM

standard Dcm4che2 toolkit

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Methods (cont.)

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Methods (cont.)

Grid-DICOM Router Act a proxy and translates between the plain

and the grid protocol Service class

Verification: Forward a C-ECHO messageStorage: Forward C-STOREQuery: Forward C-FINDRetrieve: Forward C-GET and C-MOVE

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Methods (cont.)

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Methods (cont.)

Keep router mostly independent of the architecture of the hosting system

Design the application according to the Java Management Extensions specification

JBoss JMX Implicit clustering capabilities improve the

scalability and fault tolerance of the router application

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Methods (cont.)

A number of design optimization improve the performance and stabilityOptimal thread reuse and performance

scalabilityMinimize the initial handshakingAll incoming DICOM messages are processed

in buffered memory blocks

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Methods (cont.)

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Methods (cont.)

Test Scenarios Have been tested in a partial environment of the

MediGRID test bed The security level

Full transport level encryptionMutual user/host certificationAuthorization against the gridmap fileFull delegation support of credentials

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Methods (cont.)

Three typical scenarios based on the grid image processing applicationsScenario 1: DistributionScenario 2: StorageScenario 3: Moving

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Methods (cont.)

Scenario 1: Distribution. A user distributes images from a modality. a) Conventional DICOM transferb) Encrypted DICOM Transfer c) GSI-based transferd) GSI-based transfer through a router e) The DGIS imaging solution of the Globus

incubator project MEDICUS

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Methods (cont.)

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Methods (cont.)

Scenario 2: Storage. A user sends images from an imaging device to an off-site image archive (C-STORE)

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Methods (cont.)

Scenario 3: Moving. A user requests the off-site image archive to move images to a different archive

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Methods (cont.)

Three different set:One Magnetic resonance (MR)

5 series of 100 images each (512*512, 16 bit, total 250MB)

One Computed tomography (CT) 50 series of 10 images each (512*512, 16 bit, total

250MB)Ten Computed radiology (CR) chest image

10 series of 1 image each (2140*1760, 16 bit, total approx. 800MB)

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Results and Discussion (cont.)

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Transfer Rates of Scenario 1-3 In MB/s

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Results and Discussion (cont.)

DICOM throughput increases with a lower number of single images (CR > CT = MR)

The transfer rate decreases when engaging the TLS 3des encryption

Engaging the Grid-DICOM transfer results in an almost equal, if not slightly lower transfer rate than plain encryption

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Results and Discussion (cont.)

Connecting devices through a router further reduces the transfer rate through the additional message processing costs, depending on the number of images transferred

The router solution performs in the same range as the DGIS

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Conclusion and Future Work (cont.)

Proposed a solution to integrate legacy DICOM-capable system

Developed an adaptation of the DICOM protocol stack to the GSI

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Conclusion and Future Work (cont.)

Employed a system of routers that transparently convert any traffic from pure DICOM protocol

Show the setup is a promising solution for grids based on the Globus middleware

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Conclusion and Future Work (cont.)

Future work Replace the command line clients by a user

interface Improve the router software in terms of stability

and transaction ratio

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Conclusion and Future Work (cont.)

Add modification chains for the DICOM data when passing the routers

Enhance the system by a Web service for a reliable DICOM transfer

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Thank you for your attention