SUMMARYWe describe an efficient and accurate approximation method for calculating the bandwidth that should be allocated on each link along the path of a point-to-point Multiprotocol Label Switching connection, so that the end-to-end delay D is less than or equal to a given value T with a probability γ, that is, P(D ≤ T) = γ. We model a connection by a tandem queuing network of infinite capacity queues. The arrival process of packets to the connection is assumed to be bursty and correlated and it is depicted by a two-stage MarkovModulated Poisson Process. The service times are exponentially distributed. The proposed method uses only the first queue of the tandem queuing network to construct an upper and lower bound of the required bandwidth so that P(D ≤ T) = γ. Subsequently, we estimate the required bandwidth using a simple interpolation function between the two bounds. Extensive comparisons with simulation showed that the results obtained have an average relative error of 1.25%.

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In this paper, we evaluated and compared the QoS behavior of video traffic models for H.264 AVC video. The H.264 AVC models that we evaluated are: the Markov Modulated Gamma (MMG) model, the Discrete Autoregressive (DAR) model, the second order Autoregressive AR(2) model, and a waveletbased model. These models were used to generate synthetic packet traces which were used in a simulation model to estimate the 95th percentile of the end-to-end delay, jitter and packet loss. The QoS metrics of the generated traces are compared with those of the original traces available from the Arizona State University video traces library. We observed that none of the model produces accurate results for every type of video but the MMG model produced the results closest to the actual traces.