An adaptive hybrid technique for video multicast

Periodic broadcast and scheduled multicast have been shown to be very effective in reducing the demand on sen er bandwidth. While periodic broadcast is ideally suited for very popular videos, scheduled multicast is better for less demanded objects. Work has also been dent to show that a hybrid of these techniques offers the best performance. Existing hybrid techniques, however; assume that the workload does not change with rime. This assumption! is not true for many applications, such as movie on demand digital video libraries, or electronic commerce. In this paper, we show evidence that existing scheduled multicast techniques are not suited for hybrid designs. To address this issue, we propose a new scheme, find use it to design an adaptive hybrid strategy which adjusts itself to cope with a changing workload. We provide simulation results to show that the proposed technique is significantly better than the best static approach in terms of service latency throughout, defection rate, and unfairness.