A method to reduce waiting time for heterogeneous clients considering division ratios of video data

Due to the recent popularization of digital TV broadcasting systems, continuous media data broadcasting is attracting much attention. In general broadcasting systems, although the server can repetitively broadcast the same data to many clients, they have to wait until they have received all of the data to play them. Many researchers have proposed a division-based broadcasting technique with which the server can reduce the waiting time by dividing the data into several segments and frequently broadcasting precedent segments. In division-based broadcasting, the server makes a broad-cast schedule that sets the division ratio of the video data based on time slots and available bandwidth. However, in heterogeneous client environments, since the available band-width for clients differs and the number of receivable chan-nels for clients depends on their performances, conventional methods cannot effectively reduce the waiting time. In this paper, we propose a scheduling method to reduce the waiting time for heterogeneous clients based on the division ratios of video data. We apply our proposed method to a division-based broadcasting system and evaluate the waiting time by comparing the evaluation results of simulation and computer network environments.