JOURNAL OF INFORMATION SCIENCE AND ENGINEERING 19, 531-549 (2003) 531 Adaptive Live Broadcasting for Highly-Demand Videos * HUNG-CHANG YANG, HSIANG-FU YU AND LI-MING TSENG Distributed System Laboratory Department of Computer Science and Information Engineering National Central University Chungli, 320 Taiwan E-mail: {cyht; yu}@dslab.csie.ncu.edu.tw E-mail: tsenglm@csie.ncu.edu.tw With the growth of broadband networks, Video-on-Demand (VoD) has become re- alistic. Many significant broadcasting schemes have been proposed to reduce the bandwidth requirements for stored popular videos, but they cannot be used to support live video broadcast perfectly. Herein, we propose a new broadcasting scheme, called the Adaptive Live Broadcasting (ALB) scheme, which supports live video broadcasting and performs well over a wide range of request arrival rates. From our analysis and com- parison, we find that our ALB scheme is suitable for broadcasting live video. It has sev- eral significant advantages: (1) It has the shortest maximum waiting time with fixed channels. (2) It has the lowest maximum I/O transfer requirements with a fixed maxi- mum waiting time at the client end. A simulation is employed to evaluate several live broadcasting schemes: UD, ST, AFB and ALB. The results reveal that our ALB scheme consumes the least server bandwidth. Keywords: adaptive live broadcasting scheme, network bandwidth scheduling, popular video service, video-on-demand (VoD), multimedia systems 1. INTRODUCTION With the growth of broadband networks, Video-on-Demand (VoD) [13] has become realistic. Many studies have investigated VoD. One of the important areas of research is the issue of how to distribute the top ten or twenty so-called “hot” videos more effi- ciently. Broadcasting is a promising solution. It transfers each video according to a fixed schedule and consumes a constant bandwidth regardless of the number of requests for that video. That is, the number of users watching a given video is independent of their bandwidth requirements. A basic broadcasting scheme is the batch scheme [1]. The batch scheme delays the users’ requests for a certain amount of time and serves these requests in a batch so that bandwidth consumption is reduced. However, the batch scheme still requires quite a large bandwidth for a hot video. For example, for a film that lasts 120 minutes, if each request for the film has to be served within 10 minutes, then we need to allocate 12 (120/10) video channels. Suppose a set-top-box (STB) at the client end can buffer portions of the playing video on disk. With the STB, there are many available broadcasting schemes, such as Received May 15, 2002; accepted July 25, 2002. Communicated by Biing-Feng Wang, Stephan Olariu and Gen-Huey Chen. * The work was supported in part by a research grant from the National Science Council of the ROC under contract number NSC 90-2213-E-008-049. A preliminary version of the paper was presented at the 2002 In- ternational Conference on Parallel and Distributed Systems, Chungli, Taiwan.