DIFFERENTIATED QOS BASED ON CROSS-LAYER OPTIMIZATION IN WIRELESS AD HOC NETWORKS

Abstract

Generally, real time applications needs different levels of the Quality of Service (QoS) which must be guaranteed by the underlying network infrastructure. Wireless Ad Hoc networks introduce many technological challenges in guaranteeing these stringent QoS requirements which must be addressed. Many optimization theoretic based bandwidth allocation strategies have been developed for guaranteeing some levels of QoS for some classes of competing real-time users in wireless ad hoc networks. The rapid increase in the development of different real-time applications with stringent maximum packet loss requirements in such environments and the existence of difficulties in satisfying the pre-specified QoS limits, is a great motivation for designing some type of differentiated QoS guaranteeing mechanisms that can satisfy the demands of this class of the real-time traffics. In the current work, a cross-layer optimization framework is being developed in which, based on the packet loss information from the lower layers, optimal bandwidths are assigned to the real-time applications which need some levels of the maximum packet loss guaranties. As, each real-time application needs a different level of maximum packet loss guarantee, a weighted aggregate packet loss objective function is being introduced. The weights are proportional with the importance of the packet loss mitigation for a specific application and may be associated with some negotiated Service Level Agreement (SLA). The simulation results verify the claims.