Optimal Scheduling and Adaptation for VOD on Broadband Cable Networks

Broadband Cable Networks (BCNs) is the most important form of broadband service in the US, which significantly improves the bandwidth to home. However, providing efficient Video-On-Demand (VOD) service on BCNs is still a challenging issue due to the lack of effective approaches to exploit the unique characteristics of BCNs. In this study, we address this issue by fully utilizing the characteristics of BCNs, such as subchannel sharing and potential large buffer space at cable modems. We propose an optimal full-sharing scheduling approach that minimizes the bandwidth consumption of video sessions. Through analysis and simulation, we have shown that our approach has remarkable advantages in minimizing the bandwidth consumption, compared with the previous approaches. Therefore, our approach satisfies more simultaneous VOD sessions on a fixedcapacity channel. Furthermore, we design two adaptation algorithms which not only keep bandwidth consumption minimal but also significantly reduce the mean service delay to 30% or less of the mean service delay without adaptation.