DISK I/O SCHEDULING AND COMMUNICATION I/O SCHEMES FOR MULTIMEDIA SERVER HYPERMS

In step with the trend toward multimedia information services, NEC has developed the HYPERMS multimedia server that can provide/receive to/from users with multimedia information ''on-demand'' requests by means of their terminals. This paper discusses some new technological schemes which have been proposed for multimedia data processing and realized in their design during the development. A multimedia server capable of transmitting multimedia data such as video and audio information must be able to handle a large volume of such data very effectively and efficiently. In a general multimedia server system, a large volume of data is read out through a disk I/O device and is transmitted by means of a communication I/O device. However, conventional devices of this type are not suitable for processing a large volume of the multimedia information effectively and efficiently. In particular, there is a vital technological drawback in scheduling scheme for conventional disk I/O and in memory management scheme for communication I/O. The authors have studied the most appropriate form for the disk I/O scheduling scheme and a communication I/O scheme of a multimedia server. They have established and would like to propose a new disk I/O scheduling scheme and the memory management scheme of a communication I/O which are optimal with regard to the operation of a multimedia server.