Wireless industrial monitoring and control networks: the journey so far and the road ahead

While traditional wired communication technologies have played a crucial role in industrial monitoring and control networks over the past few decades, they are increasingly proving to be inadequate to meet the highly dynamic and stringent demands of today’s industrial applications, primarily due to the very rigid nature of wired infrastructures. Wireless technology, however, through its increased pervasiveness, has the potential to revolutionize the industry, not only by mitigating the problems faced by wired solutions, but also by introducing a completely new class of applications. While present day wireless technologies made some preliminary inroads in the monitoring domain, they still have severe limitations especially when real-time, reliable distributed control operations are concerned. This article provides the reader with an overview of existing wireless technologies commonly used in the monitoring and control industry. It highlights the pros and cons of each technology and assesses the degree to which each technology is able to meet the stringent demands of industrial monitoring and control networks. Additionally, it summarizes mechanisms proposed by academia, especially serving critical applications by addressing the real-time and reliability requirements of industrial process automation. The article also describes certain key research problems from the physical layer communication for sensor networks and the wireless networking perspective that have yet to be addressed to allow the successful use of wireless technologies in industrial monitoring and control networks

Multipath Routing over Wireless Mesh Networks

Master'sMASTER OF SCIENC

Interference-Aware Routing in Wireless Mesh Networks

User demand for seamless connectivity has encouraged the development of alternatives to traditional communications infrastructure networks. Potential solutions have to be low-cost, easily deployable and adaptive to the environment. One approach that has gained tremendous attention over the past few years is the deployment of a backbone of access points wirelessly interconnected, allowing users to access the wired infrastructure via wireless multi-hop communication. Wireless Mesh Networks (WMN) fall into this category and constitute a technology that could revolutionize the way wireless network access is provided. However, limited transfer capacity and interference resulting from the shared nature of the transmission medium will prevent widespread deployment if the network performance does not meet users' expectations. It is therefore imperative to provide efficient mechanisms for such networks. Resource management encompasses a number of different issues, including routing. Although a profusion of routing mechanisms have been proposed for other wireless technologies, the unique characteristics of WMNs (i.e. fixed wireless backbone, with the possibility to embed multiple interfaces) prevent their straight forward adoption in WMNs. Moreover, the severe performance degradations that can result from the interference generated by concurrent data transmissions and environmental noise call for the development of interference-aware routing mechanisms. In this thesis, we investigated the impact of interference on the network performance of wireless mesh networks. We designed algorithms to associate routers to gateways that minimize the interference level in single-channel and multi-channel networks. We then studied the performance of existing routing metrics and their suitability for mesh networks. As a result of this analysis, we designed a novel routing metric and showed its benefits over existing ones. Finally, we provided an analytical evaluation of the probability of finding two non interfering paths given a network topology

Flow Allocation for Maximum Throughput and Bounded Delay on Multiple Disjoint Paths for Random Access Wireless Multihop Networks

In this paper, we consider random access, wireless, multi-hop networks, with multi-packet reception capabilities, where multiple flows are forwarded to the gateways through node disjoint paths. We explore the issue of allocating flow on multiple paths, exhibiting both intra- and inter-path interference, in order to maximize average aggregate flow throughput (AAT) and also provide bounded packet delay. A distributed flow allocation scheme is proposed where allocation of flow on paths is formulated as an optimization problem. Through an illustrative topology it is shown that the corresponding problem is non-convex. Furthermore, a simple, but accurate model is employed for the average aggregate throughput achieved by all flows, that captures both intra- and inter-path interference through the SINR model. The proposed scheme is evaluated through Ns2 simulations of several random wireless scenarios. Simulation results reveal that, the model employed, accurately captures the AAT observed in the simulated scenarios, even when the assumption of saturated queues is removed. Simulation results also show that the proposed scheme achieves significantly higher AAT, for the vast majority of the wireless scenarios explored, than the following flow allocation schemes: one that assigns flows on paths on a round-robin fashion, one that optimally utilizes the best path only, and another one that assigns the maximum possible flow on each path. Finally, a variant of the proposed scheme is explored, where interference for each link is approximated by considering its dominant interfering nodes only.Comment: IEEE Transactions on Vehicular Technolog

AN INNOVATIVE RADIO TRANSMISSION UTILIZING QUEUE OF MULTI-INTERFACES

Within this paper, we advise congestion aware multipath routing protocol known as EAOMDV-LB for multi radio multiple interface wireless mesh systems (WMN). A brand new type of wireless multi-hop network architecture known as Wireless Mesh Network (WMN) has lately attracted much attention. Of these programs, network congestion may be the primary reason behind lower throughput and longer delay. The protocol calculates multiple pathways using suggested airtime congestion aware (ACA) metric and performs load balancing by computing queue usage of multiple connects of the node. Furthermore, the effective load balancing technique keeps data transmission on optimal path by diverting traffic completely through overloaded area. WMNs have lately acquired lots of recognition because of their rapid deployment, instant communication abilities and support for various kinds of application. The simulation results using ns2 demonstrate that our suggested load balancing plan performs much better than AOMDV when it comes to throughput, finish-to finish delay rich in traffic density. The majority of the present routing methods for WMN’s are not shipped to evolve congestion and optimal link quality