A novel framework for cross-layer design in wireless ad hoc and sensor networks

In a wireless ad hoc or sensor network, the behavior of any protocol entity and the operations carried out by such entities impact the performance. Separation between the different layers of the OSI model has been a common practice. Nevertheless, it is the unpredictability and unreliability of the underlying wireless medium, the complexity of contention-based medium access, and the dynamic nature of wireless multi-hop networks that account for our anticipation of resorting to cross-layer interactions between the network, upper, and lower layers (application, transport, MAC and PHY) to achieve energy efficiency, reliable packet delivery, and stability, in multi-hop wireless networks. We herein propose a novel framework, namely dynamic multi-attribute cross-layer design (DMA-CLD), in which multiple, and possibly conflicting, (single-layer, cross-layer, nodal, and networking) objectives are met. To our best knowledge, this is the first time that such a multi-objective framework is proposed. More importantly, our framework can be easily extended to accommodate any number of objectives and OSI layers, provided that the proper inter-layer feedback is integrated into DMA-CLD. We study some of the key characteristics of the proposed framework and show that DMA-CLD is an efficient and computationally inexpensive mechanism via which adhering to a predefined, precedence-ordered set of objectives is possible.