• فهرست مقالات backup node

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        1 - Improving the Mean Time to Failure of the System with the New Architecture of the Main Node with the Replacement Node of Industrial Wireless Sensor Networks for Monitoring and Control using Markov Model
        Ahmadreza Zamani Mohammad Ali Pourmina Ramin Shaghaghi Kandovan
        Industrial and physical site information is sent to the monitoring center by sensors in wireless sensor networks so that they can easily control the process of a company in order to improve the optimal performance of the system until the failure occurs to monitor and co چکیده کامل
        Industrial and physical site information is sent to the monitoring center by sensors in wireless sensor networks so that they can easily control the process of a company in order to improve the optimal performance of the system until the failure occurs to monitor and control in wireless sensor networks. Sensors are exposed to a wide range of failures, possible hardware and software problems in normal conditions, extreme weather conditions or other conditions caused by harsh physical environment in the field of sensors. Therefore, there is a possibility of unpredictable failure for all types of sensors and with Industrial process monitoring, preventive status monitoring, prevented error and fault and failures. The focus of this article is to present a new architecture in improving the correct performance of the system, the replacement rate of more damaged nodes and timely replacement, at the time of the starting point of the failure, the main sensor with spare ones or healthy sensors with faulty ones. The proposed network structure is such that the spare node is placed in parallel with the main node; this method makes it possible for the spare node to be replaced in case of failure of the main node, and the failed node can be quickly repaired and put in a standby mode. Our proposed model is analyzed in terms of the average time of correct system operation until failure known as mean time to failure. In this article is presented and studied and evaluated, a new architecture to improve network performance against failure using Markov model and state probability, and mean failure rate for node fault tolerance, before failure with timely replacement in wireless sensor network. In the proposed architecture, the results show a better improvement of the system's correct performance in order to reduce the adverse effects of errors and failures and improve fault tolerance. The simulation results show that the advantage of using this method reduces the adverse effects of errors and failures and improves the optimal performance of the system in the industrial site. پرونده مقاله
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        2 - An Efficient Fault-Tolerance Routing Algorithm for Mobile Ad-hoc Networks
        Fatemeh Tavakoli Meisam Kamarei Gholam Reza Asgari
        In this paper, an efficient fault-tolerant routing algorithm for Mobile Ad-hoc Networks (MANETs) is presented. The proposed algorithm increases the network fault-tolerance using natural redundancy of Ad-hoc networks. This algorithm is carried out in two stages; 1) the s چکیده کامل
        In this paper, an efficient fault-tolerant routing algorithm for Mobile Ad-hoc Networks (MANETs) is presented. The proposed algorithm increases the network fault-tolerance using natural redundancy of Ad-hoc networks. This algorithm is carried out in two stages; 1) the selection of backup nodes 2) the selection of backup route(s). In the first stage, the proposed algorithm chooses nodes with the same path as backup nodes. Prediction and diagnosis of nodes` paths is performed through backup tables. Since the selection of backup nodes is fulfilled, the proposed algorithm begins fault-tolerance routing. For this purpose, initially the proposed algorithm provides the main route between each pair of source & destination nodes based on DSR routing algorithm. Then, from a destination node towards a source node, the backup route(s) is established between the chosen backup nodes in the first stage. Experimental results taken from NS-2 simulator demonstrate that in comparison with previous methods the proposed increases; 1) 10% the package delivery ratio against the percentages of faulty nodes and, 2) 22% package delivery ratio against the pause time of various mobile nodes. پرونده مقاله
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        3 - Fault-tolerance Enhancement in Mobile Ad-hoc Networks Using Backup Nodes
        Fatemeh Tavakoli Meisam Kamarei Gholam Reza Asgari
        Due to limitations in computing resources of mobile nodes, Mobile Ad-hoc Networks (MANETs) are very fault-prone. So far, redundancy at different levels of the network has been considered an efficient strategy to enhance the fault-tolerance of networks. Indeed, ad-hoc ne چکیده کامل
        Due to limitations in computing resources of mobile nodes, Mobile Ad-hoc Networks (MANETs) are very fault-prone. So far, redundancy at different levels of the network has been considered an efficient strategy to enhance the fault-tolerance of networks. Indeed, ad-hoc networks are extremely redundant; therefore, natural redundancy to fault tolerance enhancement has a great impact on the network performance. In this paper, a fault tolerant algorithm for MANETs has been proposed that by assigning backup node(s) to each node tries to increase in fault-tolerance. For this reason, the proposed algorithm chooses the backup nodes from among those nodes having the same movement route. The nodes movement route can be determined or predicted through the backup nodes table. Choosing backup nodes is done based on the time of nodes adjacency. Experimental results taken from NS-2 simulator indicated that in comparison to other algorithms, the proposed algorithm increases by 1) the package delivery rate in relation to the percentage of fault, and 2) the package delivery rate in relation to various mobile nodes` pause time. پرونده مقاله