Wahle A, Builtjes JH, Oswald H, Fleck E:


Secure Inter-Institutional Image Communication by using DICOM-to-DICOM Gateways.

Computers in Cardiology 1996, Indianapolis IN, IEEE Press

Page 309-312, 1996

Use of the DICOM standard for image communication between different institutions across firewalls, or within heterogeneous networks (Images) (Links)

Abstract: The establishment of the DICOM standard for communication between modalities, image archives, and applications is widely in progress. Since it is very useful to perform communications on a standardized base, we extended the meaning of DICOM communication from a local to an inter-institutional view. DICOM considers a communication between two application entities on a direct association only. Patient related data is protected by special legal restrictions, which may require the introduction of firewalls and gatekeepers by an institution. Direct communication may also be impaired by heterogeneous network designs. To transport images or other data between different networks, especially between different institutions, a number of intermediate gateways must be crossed. Conventional gatekeepers allow access by common TCP/IP protocols like TELNET or FTP only. If institutions agreed about - possibly automized - transfers of images, and both modalities and archives are conformant to DICOM, it would not make sense to transfer data by protocols like FTP. Especially, FTP does not allow proper synchronization and cannot interpret the contents of submitted data. For the purpose of forwarding a dataset from one to another application via an unlimited number of networks, we developed a set of DICOM-to-DICOM gateways. They allow the configuration of transmission paths for each pair of applications A and B. A sends a dataset to the first gateway G(0) that knows the final destination B and the optional next gateway G(1) of the transmission path. Each gateway G(i) knows how to forward a dataset received from A via G(i-1) to B via an optional further gateway G(i+1). The communication is performed by extended C-STORE and C-MOVE DIMSE services, which are confirmed with "success" only if the dataset could be delivered to the final destination. Legal requirements for transmission control are satisfied by access controls on both TCP/IP and DICOM levels, and by logging mechanisms for each request. The transfer of conventional ACR-NEMA 1.0 or 2.0 datasets was included by adding a Private SOP Class that preserves the original dataset format.