Two asymptotic analyses of the queue length distribution at a statistical multiplexer supporting heterogeneous exponential on-off sources are considered. The first analysis is performed by approximating the cell generation rate as a multidimensional Ornstein-Uhlenbeck process and then applying the Benes queueing formula. In the second analysis, we start with a system of linear equations derived from the exact expressions of the dominant eigenvalue of the matrix governing the queue length distribution. Assuming that there are a large number of sources, we obtain asymptotic approximations to the dominant eigenvalue. Based on the analyses, we define a traffic descriptor to include the mean and the variance of the cell generation rate and a burstiness measure. A simple expression for the quality of service (QoS) in cell loss rate is derived in terms of the traffic descriptor parameters and the multiplexer parameters (output link capacity and buffer size). This result is then used to quantify the factors determining the required capacity of a call taking the statistical multiplexing gain into consideration.

Discusses the allocation of the available capacity of a statistical multiplexer to serve a number of heterogeneous on-off sources, with the cell loss rate as the performance criterion. In order to avoid using potentially lengthy simulations, the authors have derived computationally efficient bounds and asymptotic approximations for the cell loss rate. The union of all partitions of the available capacity which satisfies the capacity bound and the performance criterion is defined as the capacity region. Both linear approximation and nonlinear approximation of the capacity region are investigated. It is shown that the linear approximation is reasonably accurate when the activity factors of the sources are not too high (less than 0.8). For the case where the linear approximation appears too optimistic, a simple nonlinear approximation for determining the capacity region is suggested. The accuracy of the method is demonstrated using numerical examples.>

The authors are concerned with the allocation of the available capacity of a statistical multiplexer to serve a number of heterogeneous on-off sources, with the cell loss rate as the performance criterion. In order to avoid using potentially lengthy simulations, they have derived computationally efficient bounds and asymptotic approximations for the cell loss rate. The union of all partitions of the available capacity which satisfies the capacity bound and the performance criterion is defined as the capacity region. Both linear approximation and nonlinear approximation of the capacity region are investigated. It is shown that the linear approximation is reasonably accurate when the activity factors of the sources are not too high (less than 0.8). For the case where the linear approximation appears too optimistic, a simple nonlinear approximation for determining the capacity region is suggested. The accuracy of the method is demonstrated using numerical examples.>

An approximate model is considered for characterizing aggregated cell arrivals from heterogeneous sources which may generate cells in a highly time correlated manner. The model consists of two types of on-off sources and provides enough degrees of freedom to match a number of moments of cell arrival rates as well as the time correlation of the aggregated cell arrivals. Numerical examples are presented to illustrate the accuracy of the queue length distributions obtained using the model compared with the exact results.>

A multiaccess scheme, that is a variation of movable slot time-division multiplexing and p-persistent carrier-sense multiple-access is proposed for voice only or integrated voice and data transmission in a packet radio network. Simulations are performed to examine the performance characteristics of the proposed scheme under various system parameter values. Three different sets of parameters are selected for voice transmission, and a particular set of parameters is used for integrated voice and data transmission.>

A combined random/reservation multiple access (CRRMA) scheme for packet-switched communication over a global beam satellite with on-board processing is proposed and analyzed. Channel time is divided into contiguous slots; each slot containsNminislots for transmission of request packets andN'minislots for data. WithNsubstantially smaller than the number of earth stations, collisions will occur in request packet transmissions. Two channel access algorithms for the CRRMA model are proposed: uncontrolled channel access (UCA) and controlled channel access (CCA). UCA is simpler but has an inherent stability problem particularly when the number of minislotsNis small. The CCA algorithm restricts the transmission of request packets for new arrivals to take place only when the slot is in the FREE state. WithN = 3, the CCA algorithm exhibits good delay-throughput characteristics. AsNincreases, the UCA algorithm offers stable operation. ForN \geq 5the simpler UCA algorithm is preferred over CCA.