Predictive QoS-based admission control for multiclass traffic in cellular wireless networks

Abstract

We develop the notion of quality of service (QoS) for multimedia traffic in terms of maximum call dropping probabilities independent of system load and a predefined call blocking probability profile for the different traffic classes for wireless networks of arbitrary shape and dimension. We describe two distributed predictive admission control algorithms, independent multiclass one-step prediction (IMOSP-CS and IMOSP-RES), which provide each traffic class with a given call dropping probability and a desired call blocking probability profile. Both algorithms may be seen as extensions of the multimedia one-step prediction (MMOSPRED) algorithm previously reported, which uses prediction of the overload probability in the home and neighbor cells in deciding whether to admit new users into a multiclass cellular system. The two algorithms differ in their approach to handoff call admission. The first algorithm completely shares the bandwidth among the entering handoff users while the second implements a partition-based reservation scheme. In this paper, we additionally impose a call blocking criterion that ensures a system-imposed call priority independent of the traffic in the system and which adapts to changes in the offered load. In comparing these algorithms to each other, we focus on system throughput and class independence. Both algorithms provide appropriate throughput under both homogeneous and heterogeneous traffic loading conditions while maintaining steady call dropping probabilities for each traffic class.