A parametric Linear Programming Model Describing Bandwidth Sharing Policies for ABR Traffic

We consider the fair bandwidth allocation problem of ABR calls by a Connection Admission Controller (CAC) at call setup. Its general solution is given by applying the “max-min fairness allocation policy”. Extensions of this policy take into account the Minimum Cell Rate (MCR) and the Peak Cell Rate (PCR) traffic description parameters, which are essential for ABR. These extensions are distinguished according to the existence or non-existence of weights in the policy. The weights may be defined independent of MCR or dependent on MCR. In this paper firstly we present a linear programming model, which describes in a parametric way both weighted and unweighted bandwidth allocation policies for ABR services. Because of the parametric nature of the LP model, it can be easily extended in order to take into account various bandwidth allocation policies. Secondly, we propose an unweighted fair bandwidth allocation policy in which ABR calls are grouped in categories, according to their traffic description parameters and the max-min fairness allocation policy is applied among the groups while the MCR and PCR can be taken into account for each group. Thirdly we propose a weight-based fair bandwidth allocation policy in which the number of links of an ABR connection stands for the weight.