Computer Networks and Distributed Systems
Asghar Dolatabadi; Hamid Haj Seyyed javadi
Volume 2, Issue 2 , May 2016, , Pages 49-55
Abstract
A sensor node is composed of different parts including processing units, sensor, transmitter, receiver, and security unit. There are many nodes in a sensor unit. These networks can be used for military, industrial, medicine, environmental, house, and many other applications. These nodes may be established ...
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A sensor node is composed of different parts including processing units, sensor, transmitter, receiver, and security unit. There are many nodes in a sensor unit. These networks can be used for military, industrial, medicine, environmental, house, and many other applications. These nodes may be established in the lands of enemies to monitor the relations. Hence, it is important to consider conservation of communications, declaration, and key removal. The locations of nodes are not usually defined in the networks. When a secure connection is required they can be used by symmetrical or asymmetrical encodings. A node can just make secure connection, if they are in same radio range or have a common key. In dynamic wireless sensor networks compared with static networks the sensors are moveable and can be added or removed. This research makes an attempt to investigate the challenges of key management for encoding. It also tries to solve other remained problems in this field. Therefore, distribution and key management schemes supplying security and operational requirements of sensor networks are examined in fuzzy clustering and suitable protocol for key management.
Computer Networks and Distributed Systems
Samaneh Nazari Dastjerdi; Hamid Haj Seyyad Javadi
Volume 1, Issue 2 , May 2015, , Pages 39-44
Abstract
Network sensors consist of sensor nodes in which every node covers a limited area. The most common use ofthese networks is in unreachable fields.Sink is a node that collects data from other nodes.One of the main challenges in these networks is the limitation of nodes battery (power supply). Therefore, ...
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Network sensors consist of sensor nodes in which every node covers a limited area. The most common use ofthese networks is in unreachable fields.Sink is a node that collects data from other nodes.One of the main challenges in these networks is the limitation of nodes battery (power supply). Therefore, the use oftopology control is required to decrease power consumption and increase network accessibility.In this paper, a network is modeled by a graph. Each vertex in the graphindicatesa sensor node and the edges display the communication links between them.Changes in the graph show changes in network topology and a different path to the sink.In this research, “fuzzy logic” is used for topology control. As the fuzzy logic utilizes optimized sensing radius comparing with minimum-maximum sensing radius, we expect less dead nodes, more mean residual energy and relatively more load balance in the network. At first, 2-input fuzzy algorithm was chosen. However 3-input fuzzy algorithm was also observed due to reasons explained in the main text. In both algorithms, we haveload balance in network and prolong network lifetime. Unreachable paths are less encountered with higher rates of packet delivery. The final standard deviation (STD) reaches to its minimum level, while the residual energy in sensors remains close to each other.