Wide-area-distributed storage system for multimedia database

We have developed a wide-area-distributed storage system for multimedia databases that minimizes the possibility of simultaneous failure of multiple disks in the event of a major disaster. It features a RAID system whose member disks are spatially distributed over a wide area Each node has a device that includes the controller of the RAID and the controller of the member disks controlled by other nodes. The devices in the node are connected to a computer using fiber optic cables and communicate using Fibre-Channel technology. Any computer at a node can utilize multiple devices connected by optical fibers as a single "virtual disk". The advantage of this system structure is that devices and fiber optic cables are shared by the computers. In this report, we first describe our proposed system and a prototype we used for testing, Then we discuss its performance, i.e., how the read and write throughputs are affected by data-access delay, the RAID level, and queuing.