Abstract
With the rapid advances on information appliance technologies, some powerful client devices, e.g., set top box and digital video recorder, are commonly used to enhance digital TV broadcasting services nowadays. In this thesis, we propose a virtual channel platform by organizing these client devices to virtually support each user a dedicated channel according to her/his demand. In the proposed platform, a peer-to-peer video delivery architecture is introduced to improve the availability of each video by means of sharing the cache buffers and network bandwidth of these client devices. In addition, each video is partitioned into many small segments before it is shared in this peer-to-peer network, because different parts of the video could have different popularities. Therefore, a virtual channel can be constructed by retrieving these video segments and composing them into a long video playout sequence. However, to retrieve these small segments over a large scale peer-to-peer overlay network could cause relatively large query overhead. To reduce the query overhead, we propose a virtual stream mechanism by aggregating popular adjacent video segments to logically form a long video object. Thus, the number of video objects in a virtual channel can be decreased, implying that the total number of queries is also reduced. Through some simulation results, the proposed virtual channel platform exhibits that it can improve the service performance.