A design methodology for fault-tolerance in a DICOM-compliant data storage grid

With the increasing demand of PAC systems, more and more examinations are acquired by healthcare institutions which results in an enormous amount of image data and metadata information that needs to be archived and retrieved especially during disaster recovery. Last year we presented a Data Storage Grid (DSG) architecture based on the five-layer architecture design for Grid technology that provides 99.999% up time. The proposed solution was implemented as a three-site testbed and was developed using Globus 3.2 Toolkit. A grid architecture built on Globus middleware achieves reliability and availability through the distribution of hardware components and services. However, a DICOM-compliant DSG requires a Metadata Catalog to provide the DICOM header information available to DSG clients. For this reason, this paper describes the continued development of the DSG utilizing DICOM and IHE standards including the development of a fault-tolerant Metadata Catalog for a DICOM-compliant data grid environment.