Efficient utilization of buffer storage in conservative staircase broadcasting scheme

The staircase scheme requires minimum buffer storage among all the broadcasting schemes that provides the video services. It however does not always deliver the video data to users in time. This problem has been overcome in the conservative staircase scheme, but the scheme requires more resources especially the buffer storage. In the conservative staircase scheme, the video is divided into segments depending upon the number of video channels allocated to it by the video server. The bandwidth of a video channel is equal to the viewing rate of the video. The segments are further divided into subsegments and the video channels into subchannels in such a way that a subchannel transmits all the subsegments of a single segment. In this paper, we propose a new mechanism for utilizing the buffer storage efficiently in the conservative staircase scheme. In the proposed scheme, the segments transmitted by each of the video channels are arranged in decreasing order of their indices. By doing this, the data of the segments can be delayed without failing their availability to the users in time. By delaying downloading of the data, only that data is stored in the buffer storage at the user´s site that is needed immediately and in very near future. This scheme not only provides the video services using less storage space but also requires less disk transfer rate as compared to the conservative staircase scheme. Furthermore, the complexity of this scheme is much less than that of the conservative staircase scheme because it does not require the segments to be divided into subsegments and the video channels into subchannels¹.