Cooperating leaky bucket for average rate enforcement of VBR video traffic in ATM networks

Because of the burstiness of video traffic, a very large sampling interval is needed to obtain acceptable cell loss probability. Previous studies reported very high cell loss probabilities for well-behaved sources when using the leaky bucket mechanism (LB) to police VBR video sources. In this paper, a mean rate policing mechanism called cooperating leaky bucket (CLB) is introduced. This mechanism can attain better cell loss probability by sharing the leaky buckets among all sources. In addition, it guarantees that the cell loss probability will never be higher than that obtained by LB. Depending on the number of traffic sources available, the cell loss probability can be significantly reduced when compared to LB. At the same time, the combined traffic entering the network is enforced to below the total negotiated traffic rate. Moreover, the additional overhead due to the implementation of CLB is minimal.