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101.
Mohammed Al‐Hubaishi Celal eken Ali Al‐Shaikhli 《International Journal of Communication Systems》2019,32(17)
Energy consumption is one of the most important design constraints when building a wireless sensor and actuator network since each device in the network has a limited battery capacity, and prolonging the lifetime of the network depends on saving energy. Overcoming this challenge requires a smart and reconfigurable network energy management strategy. The Software‐Defined Networking (SDN) paradigm aims at building a flexible and dynamic network structure, especially in wireless sensor networks. In this study, we propose an SDN‐enabled wireless sensor and actuator network architecture that has a new routing discovery mechanism. To build a flexible and energy‐efficient network structure, a new routing decision approach that uses a fuzzy‐based Dijkstra's algorithm is developed in the study. The proposed architecture can change the existing path during data transmission, which is the key property of our model and is achieved through the adoption of the SDN approach. All the components and algorithms of the proposed system are modeled and simulated using the Riverbed Modeler software for more realistic performance evaluation. The results indicate that the proposed SDN‐enabled structure with fuzzy‐based Dijkstra's algorithm outperforms the one using the regular Dijkstra's and the ZigBee‐based counterpart, in terms of the energy consumption ratio, and the proposed architecture can provide an effective cluster routing while prolonging the network lifetime. 相似文献
102.
Georgios Kioumourtzis Christos Bouras Apostolos Gkamas 《International Journal of Network Management》2012,22(3):216-234
Mobile ad hoc networks (MANETs) are of much interest to both the research community and the military because of the potential to establish a communication network in any situation that involves emergencies. Examples are search‐and‐rescue operations, military deployment in hostile environments, and several types of police operations. One critical open issue is how to route messages considering the characteristics of these networks. The nodes act as routers in an environment without a fixed infrastructure, the nodes are mobile, the wireless medium has its own limitations compared to wired networks, and existing routing protocols cannot be employed, at least without modifications. Over the last few years, a number of routing protocols have been proposed and enhanced to address the issue of routing in MANETs. It is not clear how those different protocols perform under different environments. One protocol may be the best in one network configuration but the worst in another. This article provides an analysis and performance evaluation of those protocols that may be suitable for military communications. The evaluation is conducted in two phases. In the first phase, we compare the protocols based on qualitative metrics to locate those that may fit our evaluation criteria. In the second phase, we evaluate the selected protocols from the first phase based on quantitative metrics in a mobility scenario that reflects tactical military movements. The results disclose that there is no routing protocol in the current stage without modifications that can provide efficient routing to any size of network, regardless of the number of nodes and the network load and mobility. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
103.
Tirthankar?GhoshEmail author Niki?Pissinou Kami?Sam?Makki 《Mobile Networks and Applications》2005,10(6):985-995
Designing a trusted and secure routing solution in an untrustworthy scenario is always a challenging problem. Lack of physical
security and low trust levels among nodes in an ad hoc network demands a secure end-to-end route free of any malicious entity.
This is particularly challenging when malicious nodes collude with one another to disrupt the network operation. In this paper
we have designed a secure routing solution to find an end-to-end route free of malicious nodes with collaborative effort from
the neighbors. We have also extended the solution to secure the network against colluding malicious nodes, which, to the best
of our knowledge, is the first such solution proposed. We have also proposed a framework for computing and distributing trusts
that can be used with out trusted routing protocol. Our proposed framework is unique and different from the other schemes
in that it tries to analyze the psychology of the attacker and quantifies the behavior in the computational model. Extensive
simulation has been carried out to evaluate the design of our protocol.
Partially funded by Department of Defense Award No. H98230-04-C-0460, Department of Transportation Project No. FL-26-7102-00
and National Science Foundation Grant Nos. ANI-0123950 and CCR-0196557.
Tirthankar Ghosh is a PhD candidate in the Telecommunications and Information Technology Institute at Florida International University. His
area of research is routing security and trust computation in wireless ad hoc and sensor networks. He received his Bachelor
of Electrical Engineering from Jadavpur University, India and Masters in Computer Engineering from Florida International University.
Dr. Niki Pissinou received her Ph.D. in Computer Science from the University of Southern California, her M.S. in Computer Science from the
University of California at Riverside, and her B.S.I.S.E. in Industrial and Systems Engineering from The Ohio State University.
She is currently a tenured professor and the director of the Telecommunication & Information Technology Institute at FIU.
Previously Dr. Pissinou was a tenured faculty at the Center for Advanced Computer Studies at the University of Louisiana at
Lafayette where she was also the director of the Telecommunication & Information & Technology Laboratory partially funded
by NASA, and the co-director of the NOMAD: A Wireless and Nomadic Laboratory partially funded by NSF, and the Advanced Network
Laboratory. Dr. Pissinou is active in the fields computer networks, information technology and distributed systems.
Dr. Kami (Sam) Makki has earned his Ph.D. in Computer Science from the University of Queensland in Brisbane Australia, his Masters degree in Computer
Science and Engineering from the University of New South Wales in Sydney Australia, and his Bachelor and Masters Degrees in
Civil Engineering from the University of Tehran Iran. Before joining the department of Electrical Engineering and Computer
Science at the University of Toledo he has held a number of academic positions and research appointments at the Queensland
University of Technology in Brisbane, Royal Melbourne Institution of Technology in Melbourne and at The University of Queensland
in Brisbane Australia. He is an active researcher in the fields of distributed systems, databases, mobile and wireless communications,
and has more than 30 publications in peerreviewed journals and international proceedings. He has served as a chair and technical
program committee member and reviewer for a number of IEEE and ACM sponsored technical conferences and has received a number
of achievement awards. 相似文献
104.
当前,基于社区的机会网络研究在模型上还有待完善,在社区间的路由算法没有考虑消息的传输效率,只采用简单的分发等待路由算法,使得路由效率较低。为此,对社区模型进行了改进,加入节点回归因素,并在此模型下提出了新的路由算法NBR。在社区内采用混合路由算法,并加入了正反馈思想重新计算节点活跃度。在社区间采用查询路由表和判断节点回归相结合的方法,利用节点回归的特性提高转发效率。仿真结果表明,在改进后的社区模型下,NBR算法使得社区间和社区内的消息传输成功率得到了提升,有效的降低了网络资源的消耗。 相似文献
105.
Ying‐Dar Lin Te‐Lung Liu Shun‐Hsien Wang Yuan‐Cheng Lai 《International Journal of Communication Systems》2019,32(14)
With the growth of network traffic volume, link congestion cannot be avoided efficiently with conventional routing protocols. By utilizing the single shortest‐path routing algorithm from link state advertisement information, standard routing protocols lack of global awareness and are difficult to be modified in a traditional network environment. Recently, software‐defined network (SDN) provided innovative architecture for researchers to program their own network protocols. With SDN, we can divert heavy traffic to multiple paths in order to resolve link congestion. Furthermore, certain network traffics come in periodic fashion such as peak hours at working days so that we can leverage forecasting for resource management to improve its performance. In this paper, we propose a proactive multipath routing with a predictive mechanism (PMRP) to achieve high‐performance congestion resolution. PMRP has two main concepts: (a) a proactive mechanism where PMRP deploys M/M/1 queue and traffic statistics to simulate weighted delay for possible combinations of multipaths placement of all subnet pairs, and leverage genetic algorithm for accelerating selection of optimized solution, and (b) a predictive mechanism whereby PMRP uses exponential smoothing for demand traffic volumes and variance predictions. Experimental results show a 49% reduction in average delay as compared with single shortest routing, and a 16% reduction in average delay compared with utilization & topology‐aware multipath routing (UTAMP). With the predictive mechanism, PMRP can decrease an additional 20% average delay. Furthermore, PMRP reduces 93% of flow table usage on average as compared with UTAMP. 相似文献
106.
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110.
With the increasing demands for mobile wireless sensor networks in recent years, designing an energy‐efficient clustering and routing protocol has become very important. This paper provides an analytical model to evaluate the power consumption of a mobile sensor node. Based on this, a clustering algorithm is designed to optimize the energy efficiency during cluster head formation. A genetic algorithm technique is employed to find the near‐optimal threshold for residual energy below which a node has to give up its role of being the cluster head. This clustering algorithm along with a hybrid routing concept is applied as the near‐optimal energy‐efficient routing technique to increase the overall efficiency of the network. Compared to the mobile low energy adaptive clustering hierarchy protocol, the simulation studies reveal that the energy‐efficient routing technique produces a longer network lifetime and achieves better energy efficiency. 相似文献