Energy Saving Aspects and Services for Cooperative Wireless Networks

Summary. This chapter describes the implementation of wireless cooperative networks. The application was developed to prove energy savings for cooperative mobile devices. 16.1 Motivation As previously introduced, cooperation among mobile devices controlled by a cellular network is a novel wireless architecture capable of overcoming problems and limits encountered by conventional wireless networks. To prove these claims, a very simple application has been implemented to advocate the use of cooperative behavior in wireless networks. Furthermore the application can act in a stand-alone fashion too, without cooperation. Both approaches are compared with each other. The application itself underlies the same concept as BitTorrent in the wired world. In the first step we are not focusing on a commercial application. Larger interest lies in the understanding of the cooperative concepts and its related performance compared to state-of-the-art technologies. In the end of the chapter we will implement the new cooperative concept in the SymTorrent application explained before. Chapter 17; Summary. This chapter provides an introduction to cross-layer protocol design. Cross-layer design is needed in order to enhance data transmission across especially wireless network connections. This enhancement is achievable by being able to optimize certain parameters jointly across multiple layers instead of considering each layer separately. Cross-layer protocol design is a principle that provides the possibility of enhancing the architecture and operation of the layered protocol stack by allowing communication between nonadjacent layers as an extension of what is possible in the OSI model. We briefly summarize the layered network protocol stack concept of the ISO OSI model and explain cross-layer communication in this context. We provide an overview of di.erent categories of exchanging data across layers of the network protocol stack and point out advantages and drawbacks of di.erent approaches. We provide examples from the literature of such approaches. Similarly, we review a number of recent examples from research literature of how cross-layer protocol design is being put to use. The examples provide an overview of which layers are involved in di.erent cross-layer optimization approaches. The examples also provide an overview of which technological areas are currently considered in - and which optimization techniques employ - cross-layer design.