Starting time selection and scheduling methods for minimum cell loss ratio of superposed VBR MPEG video traffic

The arrangement of the I-picture starting times of multiplexed variable bit rate (VBR) MPEG videos may significantly affect the cell loss ratio (CLR) characteristics of superposed traffic. In this paper, we deal with the problems due to the starting time arrangement of VBR MPEG videos. VBR MPEG video traffic is modeled by a sequence with time-varying and periodic picture-type dependent rate envelopes. From extensive investigations into the relationships between the starting time arrangement and the queueing performance, it is shown that the average power of superposed VBR MPEG video traffic can be a good measure for the burstiness of the traffic. Then, we can derive a starting time selection method for a newly requested VBR MPEG video that can minimize the CLR as well as the peak cell rate of the superposed traffic including the new request itself, and an efficient scheduling method called MC-scheduling is also proposed as an application of the starting time selection method. The exactness and efficiencies of the proposed methods are shown by comparing them with other scheduling methods in terms of the smoothness and the CLR performances.