Full-Sharing Optimal Scheduling for VOD Service on Broadband Cable Networks

Cable Access Networks (CANs) have become one of the most important forms of broadband services, which significantly improve the bandwidth to home and spur many multimedia applications to real life. However, providing efficient Video-On-Demand (VOD) service on CANs is still a challenging issue due to the lack of effective approaches to exploit the unique characteristics of CANs. In this study, we address the scheduling issue in the VOD service over CANs by fully utilizing the characteristics of CANs, such as subchannel sharing and potential large buffer space at CAN clients. We propose an optimal full-sharing scheduling approach that minimizes the bandwidth consumption of streaming sessions. Through analysis and simulation, we have shown that our approach has remarkable advantages in minimizing the bandwidth consumption of VOD service on CANs, compared with the previous approaches. As a result, our approach can satisfy more simultaneous VOD sessions on a fixed-capacity 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.