Towards adaptive, robust and self-organizing multi-hop wireless networks.

摘要

The growing deployment of wireless technology and infrastructure is enabling a variety of new applications in many different areas. These applications necessitate a new set of requirements for network support. While progress has enabled numerous applications over the Internet, less is known about how to support these applications in wireless networks due to the unique characteristics of wireless communications and the demanding application requirements. Solutions should be able to adapt to the highly variable nature of wireless channels. They also should provide robust support to meet the desired quality of service in resource-limited wireless networks. As both the number of devices and the network size increase, it is also important that network support be scalable and self-organizing.; This dissertation addresses the problem of providing network support for emerging media-rich applications in the future wireless Internet. The topic is addressed using a systems approach at multiple protocol layers as well as utilizing cross-layer interactions. Methods for enabling adaptive, robust, and self-organizing wireless network support are presented. We derive network and application characteristics from testbed experiments and evaluate our solutions through realistic simulations.; Our MAC scheduling algorithm and heterogeneous routing protocol allow differentiated service for different traffic classes to help meet the stringent quality constraints of media-rich traffic delivery. The differentiation mechanisms are designed so that channel condition and network heterogeneity are taken into account, thereby providing network adaptations and channel efficiency improvement.; The model-based service quality prediction mechanism accurately estimates channel utilization and predicts flow service quality, both of which are essential for multimedia delivery. The admission control mechanism, based on accurate service quality prediction, further enables robust application support by ensuring satisfactory service quality and preventing waste of network resources.; The dynamic addressing mechanism uses a scalable self-organizing protocol and provides fundamental services to enable upper layer applications. The application-oriented routing algorithm provides a viable solution to connect independent wireless networks to the current Internet infrastructure, a mechanism we foresee will be an important component of the future wireless Internet.