Request based data delivery in video-on-demand services

In unified video-on-demand (UVoD) architecture, the logical channels are classified as multicast and unicast channels. The multicast channels provide services periodically and are independent of the user requests, whereas the unicast channels are used to provide services to the individual users. In that architecture, the optimal number of unicast channels has been reported to be independent of the request arrival rate. This result seems to be less accurate as the number of logical channels is affected by the request arrival rate. In this paper, we propose a more accurate study in which the number of unicast channels is shown to be explicitly dependent on the request arrival rate. In addition, for providing immediate services to the users, the number of unicast channels is much less than that of the UVoD architecture. The other important point of this study is that it can provide services for both less popular and more popular videos. However, for more popular videos all channels should be multicast channels