An overview of techniques to support continuous retrieval of multimedia objects

Multimedia information systems have emerged as an essential component of many application domains ranging from library information systems to entertainment technology. However, most implementations of these systems (based on a workstation) cannot support a continuous display of multimedia objects and suffer from frequent disruptions and delays termed hiccups. This is due to the low I/O bandwidth of the current disk technology, the high bandwidth requirement of multimedia objects, and the large size of these objects which requires them to be almost always disk resident. One approach to resolve this limitation is to decluster a multimedia object across multiple disk drives in order to employ the aggregate bandwidth of several disks to support its continuous retrieval (and display). To support simultaneous display of several multimedia objects for different users, the system can replicate data across multiple groups of disk drives in a virtual manner. This paper provides an overview of: 1) techniques to manage the replicas of objects, and 2) strategies for grouping the disk drives when the database consists of a mix of media types.