Efficient transport of stored video using stream scheduling and window-based traffic envelopes

We present efficient scheduling schemes for transporting archived MPEG-coded video over a constant-bit-rate (CBR) channel. A video source is characterized by a time-varying traffic envelope, which constitutes an upper bound on the actual bit rate. To provide a relatively tight bound, window-based envelopes are used in which the bound is based on fixed-length segments of the movie. Using such envelopes, we show that video streams can be scheduled for transmission over the network such that the per-stream allocated bandwidth is significantly less than the source peak rate. In certain cases, a reduction of up to 85% of the source peak rate was achieved. Bandwidth gain is obtained via statistical multiplexing, while providing stringent, deterministic quality of service. Online procedures for bandwidth computation and admission control under the examined scheduling schemes are presented