01491nas a2200145   4500008004100000245006200041210006200103300001600165520096300181100002101144700002301165700001901188700001601207856012201223       2003                        eng d00aCompetitive Video on Demand Schedulers for Popular Movies0 aCompetitive Video on Demand Schedulers for Popular Movies  aPP. 49 - 613 a<p>In this paper we investigate the online video on demand problem, namely having to accept or reject a request for a movie without knowing the future requests. We present online movie-scheduling schemes that implement the principles of refusal by choice and delayed noti- 4cation. A novel way to schedule movies that exploits the knowledge of the distribution of the preference of requests for movies, is shown to have a competitive ratio that outperforms all the previously knownschemes inpractical situations. Infact, our scheduler has a competitive ratio bounded above by a constant, independent of the number of the users, channels, or movies, in the case that a large fraction of the requests tends to concentrate in a small number of movies. We extend our approach by presenting an “adaptive” randomized scheduler which initially is not aware of the movie popularities but it adapts to it, and achieves the same asymptotic competitive ratio.</p>
1 aBouras, Christos1 aKapoulas, Vaggelis1 aSpirakis, Paul1 aPantziou, G  uhttp://telematics.upatras.gr/telematics/publications/competitive-video-demand-schedulers-popular-movies-0?language=el