Unicast and multicast combination of unified bandwidth allocation model on cable network

In video-on-demand (VoD) systems, a number of sophisticated architectures have been proposed to provide instantaneous services through the use of unicast and multicast technologies. Most of the architectures adopt a delivery scheme independent of the popularity of the requested video and the current system load, which fails to achieve a better bandwidth utilization ratio. This paper presents a unified bandwidth allocation architecture combining both unicast and multicast. Furthermore, a bandwidth allocation algorithm is proposed to control the way the bandwidth channel is allocated based on the popularity of the requested video and the current request arrival rate. The simulation results show that the proposed architecture and algorithm improve the system throughput at peak time without much influence on most channelspsila interactive ability and increase interactive clients at off-peak time.