Enabling Differentiated QoS Based on Cross-Layer Optimization in Wireless Ad Hoc Networks

Many optimization theoretic based bandwidth allocation strategies have been developed for guaranteeing some levels of Quality of Service (QoS) for some classes of competing real-time users in wireless ad hoc networks. By considering different objective functions (such as congestion level, constrained delay and so on), the researchers propose some optimization frameworks by which the problem can be solved. 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 technique is being introduced in which, based on the packet loss information from the lower layers, some optimal bandwidth is 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. The simulation results verify the claims.