A Seamless Broadcasting Scheme with Live Video Support

Broadcasting schemes, such as the fast broadcasting and harmonic broadcasting schemes, significantly reduce the bandwidth requirement of video-on-demand services. In the real world, some history events are very hot. For example, every year in March, thousands of people connect to Internet to watch the live show of Oscar Night. Such actions easily cause the networks contested. However, the schemes mentioned previously cannot alleviate the problem because they do not support live broadcasting. In this paper, we analyze the requirements for transferring live videos. Based on the requirements, a time skewing approach is proposed to enable the broadcasting schemes to support live broadcasting. However, the improved schemes require extra bandwidth for live broadcasting once the length of live shows exceeds the default. Accordingly, we proposed a scalable binomial broadcasting scheme to transfer live videos using constant bandwidth by increasing clients’ waiting time. When the scheme finds that the length of a video exceeds the default, it doubles the length of to-be-played segments and then its required bandwidth is constant. 1. Introduction With the growth of broadband networks, the video-on-demand (VOD) [1] becomes realistic. Many studies start investigating VOD. One of important areas is to explore how to distribute the top ten or twenty so-called hot videos more efficiently. Broadcasting is one of the promising solutions. It transfers each video according to a fixed schedule and consumes constant bandwidth regardless of the presence or absence of requests for the video. That is, the system’s bandwidth requirement is independent of the number of users watching a given video. A basic broadcasting scheme is the batch scheme [2], which postpones the users’ requests for a certain amount of time and serves these requests in batch so that its bandwidth consumption is reduced. However, the batch scheme still requires quite large bandwidth for a hot video. For example, given a video of 120 minutes, if the maximum clients’ waiting time equals 10 minutes, the required bandwidth is 12 , where is the video playout rate. Many broadcasting schemes were proposed to further reduce the bandwidth requirement by using a set-top box (STB) at the client end. The schemes include the fast broadcasting (FB) [3, 4], pagoda broadcasting (PB) [5], new pagoda broadcasting (NPB) [5], recursive-frequency splitting (RFS) [6], staircase broadcasting (SB) [7], and harmonic broadcasting (HB) [8, 9] schemes, which divide a video into multiple segments and distribute them through several