Wireless mesh network

About: Wireless mesh network is a research topic. Over the lifetime, 13600 publications have been published within this topic receiving 221035 citations. The topic is also known as: WMN.

Wireless distributed computing: a survey of research challenges

Abstract: Recent advancements in radio technology provide great flexibility and enhanced capabilities in executing wireless services. One of these capabilities that can provide significant advantages over traditional approaches is the concept of collaborative computing in wireless networks. With collaborative radio nodes, multiple independent radio nodes operate together to form a wireless distributed computing (WDC) network with significantly increased performance, operating efficiency, and abilities over a single node. WDC exploits wireless connectivity to share processing- intensive tasks among multiple devices. The goals are to reduce per-node and network resource requirements, and enable complex applications not otherwise possible, e.g., image processing in a network of small form factor radio nodes. As discussed in this article, WDC research aims to quantify the benefits of distributed processing over local processing, extend traditional distributed computing (DC) approaches to allow operation in dynamic radio environments, and meet design and implementation challenges unique to WDC with the help of recently available enabling technologies, such as software radios and cognitive radios.

A Contention-Aware Routing Metric for Multi-Rate Multi-Radio Mesh Networks

Abstract: We present a new routing metric for multi-rate multi-radio mesh networks, which takes into account both contention for the shared wireless channel and rate diversity in multi-radio multi-channel mesh networks. A key property of the proposed contention-aware transmission time (CATT) metric is that it is isotonic, hence can be applied to link-state routing protocols. We have implemented the CATT metric in the OLSR routing protocol, and evaluate it in a test-bed with mesh nodes each equipped with four radio interfaces. Our experiments show that the proposed routing metric significantly outperforms other metrics that have appeared in the literature, in a number of scenarios that correspond to different mesh network topologies.

A channel and rate assignment algorithm and a layer-2.5 forwarding paradigm for multi-radio wireless mesh networks

Abstract: The availability of cost-effective wireless network interface cards makes it practical to design network devices with multiple radios which can be exploited to simultane-ously transmit/receive over different frequency channels. It has been shown that using multiple radios per node increases the throughput of multi-hop wireless mesh networks. However, multi-radios create several research challenges. A fundamental problem is the joint channel assignment and routing problem, i.e., how the channels can be assigned to radios and how a set of flow rates can be determined for every network link in order to achieve an anticipated objective. This joint problem is NP-com-plete. Thus, an approximate solution is developed by solving the channel assignment and the routing problems separately. The channel assignment problem turns out to be the problem to assign channels such that a given set of flow rates are schedulable and itself is shown to be also NP-complete. This paper shows that not only the channels but also the transmission rates of the links have to be properly selected to make a given set of flow rates schedulable. Thus, a greedy heuristic for the channel and rate assignment problem is developed. Algorithms to schedule the resulting set of flow rates have been proposed in the literature, which require synchronization among nodes and hence modified coordination functions. Unlike previous work, in this paper a forwarding paradigm is developed to achieve the resulting set of flow rates while using a standard MAC. A bi-dimensional Markov chain model of the proposed forwarding paradigm is presented to analyze its behavior. Thorough performance studies are con-ducted to: a) compare the proposed greedy heuristic to other channel assignment algorithms; b) analyze the behavior of the forwarding paradigm through numerical simulations based on the Markov chain model; c) simulate the operations of the forwarding paradigm and evaluate the achieved network throughput.

Distributed ad hoc network protocol using synchronous shared beacon signaling

Abstract: A method for forming a protocol structure for use in an ad hoc, distributed, scaleable wireless sensor node network which enables nodes to join the network autonomously without there being a designated, permanent central time reference and for enabling such nodes to synchronize timing with each other and with other nodes in the network. The method involves discovering the active channel changing sequence used by the network, synchronizing communications of a new node with the remainder of the nodes in the network and scanning communications channels to detect merging clusters of nodes.