A novel scheduling scheme for serving VBR-encoded multimedia streams

We propose a novel scheduling scheme, in which a new user is admitted for service by a multimedia server only if the service requirements of all the existing users and the new user can be satisfied. Each user is assumed to be requesting a variable bit rate (VBR) MPEG2 encoded media stream. The scheduling scheme maximizes the number of streams that can be served concurrently. The quality of service is guaranteed in terms of the fraction of the frames that may be dropped for a user. When a new request arrives, the admission control algorithm estimates the fraction of frames that may have to be dropped for the users assuming that the new request is accepted. If the fraction of frames is more than the drop rate committed to the users, the request is rejected, otherwise it is accepted. Our scheme is much more simpler than the schemes suggested in the literature and results in better utilization of the resources, and at the same time provides guaranteed QoS to the users requesting predictive service. Extensive simulations have been conducted to demonstrate the effectiveness of this scheduling scheme.