ALGORITHMS FOR DESIGNING MULTIMEDIA SERVERS

In this paper, we propose a novel adaptive admission control algorithm , in which a client is admitted for service by a multimedia server onl y if the extrapolation from the past measurements of the storage serve r performance characteristics indicates that the service requirements of all the clients can be met satisfactorily. Each client may request the retrieval of a variable bit rate (VBR) encoded media stream, and m ay require a different quality of service. We also present a disk sche duling algorithm that minimizes both seek time and rotational latency incurred while accessing a sequence of media blocks from disk. We exam ine the effects of a finite read-ahead on the quality of service provi ded to each admitted client. The effectiveness of the admission contro l and disk scheduling algorithms is demonstrated through extensive sim ulations.