Abstract: A multimedia server retrieves blocks of data from a storage medium and supplies the blocks in the form of data streams to users. The streams include a group of high bit rate streams and a group of low bit rate streams. The system has a reader for in a sweep reading data blocks from the storage medium for a selected group of streams and for storing the data blocks in respective buffers. The system further has a scheduler for determining which of the streams is to be serviced, i.e. for which of the streams a block is to be read, in the next sweep of the reader. The scheduler according to the invention is operative to determine to service a low bit rate stream less often than a high bit rate stream.

Abstract: The invention relates to a storage system (100) such as a video on demand system, comprising a plurality of storage units (110-120) such as disk drives. Each one of the storage units (110-120) has a number of storage zones (121-126) with mutually different expected data retrieval times. Data is stored in data units, with each data unit comprising N blocks, wherein N≧2. The blocks of a data unit are distributed over the storage units (110-120). The blocks comprise redundant information such that any one of a plurality of selections comprising N−K of the N blocks suffices for retrieving the data unit, wherein K≧1. For retrieving a data unit from the storage units (110-120), a reader determines which N−K of the N blocks to retrieve on the basis of a selection procedure. In accordance with the invention, the selection procedure takes into account the expected data retrieval times in order to optimize bandwidth utilization.