Bandwidth allocation and admission control schemes for the distribution of MPEG streams in VOD systems

Large-scale deployment and successful commercialization of digital video systems will strongly depend on their ability to provide cost-effective services to potential customers. Network bandwidth is one of the major factors that impacts the cost of a video service. In this paper, we investigate efficient bandwidth allocation and call admission control (CAC) strategies for transporting MPEG-compressed video over a wide-area network. These strategies are based on exploiting the periodic nature of MPEG compression for the purpose of reducing the bandwidth requirements while maintaining a high level of quality of service. We derive a theoretical bound on the call blocking probability at the server, and show how this bound can be used in off-line capacity planning and resource dimensioning. For on-line operation, we provide a simple CAC test that can be used in conjunction with the proposed bandwidth allocation and stream scheduling strategies. The effectiveness of our approach is evaluated through simulations of a video distribution network that consists of a server and several switches. Issues related to its practicality and implementation feasibility are discussed.