Simulation of Nonstop Operation of Archival Server Using Optical Disk Cluster Drive

Abstract

When preserving present culture, degradation of such heritage by the environment is an inevitable issue. Digital archival is the common practice for preserving culture. However, there are problems of media degradation and obsolescence of the system used. Consequently, the data has to be migrated to the next-generation media periodically. Digitized heritage has to be referenced by customers so that enough funds to maintain the system can be obtained. An optical disk cluster drive is realistic candidate for an archival server. The service has to be supplied continuously. When the disks become full, it is possible to remove less frequently accessed data to off-line data shed without stopping the archival server because the cluster drive functions correctly even though one drive is detached [K. Tanaka and F. Ichikawa: Proc. SPIE 4090 (2000) 258]. In order to investigate the performance of such an archival server, a simulator was developed. In this paper, we describe the structure of the archival server simulator and the performance of the archival server. It became clear that optical cluster drives can be used as archival servers.