Current analysis on Cell Loss Control mechanisms for ATM networks are usually based on aggregate traffic and infinite interval. Since Quality of Service (QOS) may be required for individual connections in finite intervals, the results derived using the above conditions are not adequate to provide this type of QOS guarantee. Transient analysis for individual connections is needed. Our model is built on a common cell loss control mechanism called Partial Buffer Sharing (PBS). Formulae for cell loss rates and queue length distributions have also been derived....[ Read more ]

Current analysis on Cell Loss Control mechanisms for ATM networks are usually based on aggregate traffic and infinite interval. Since Quality of Service (QOS) may be required for individual connections in finite intervals, the results derived using the above conditions are not adequate to provide this type of QOS guarantee. Transient analysis for individual connections is needed. Our model is built on a common cell loss control mechanism called Partial Buffer Sharing (PBS). Formulae for cell loss rates and queue length distributions have also been derived.

A problem with PBS is that while the overall cell loss probability is maintained at an acceptable level, the loss probability of individual classes of cells may be poor. It is useful to constrain the violation probability of each class of cells. A new cell loss control mechanism called Threshold-based Loss Balancing (TLB) will be presented which provides the flexibility of decreasing the violation probability of one class at the expense of another class. As a result, the number of connections that can be accepted for a given total network bandwidth may be increased. PBS is shown to be a special case of TLB. Transient Analysis for individual connections is performed on TLB based on simple Bernoulli arrivals for homogeneous connections. Formulae to calculate the approximate cell loss and queue length distributions have been derived. Comparisons of TLB and PBS on selected operating conditions reveal that TLB will increase the number of connections that can be accepted if some proportion of cells can be discarded.