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Han-xing Wang Xi Hu Qin Zhang 《应用数学学报(英文版)》2007,23(2):235-244
In this paper,we present a random graph model with spatial reuse for a mobile ad hoc network(MANET) based on the dynamic source routing protocol.Many important performance parameters of theMANET are obtained,such as the average flooding distance (AFD),the probability generating function of theflooding distance,and the probability of a flooding route to be symmetric.Compared with the random graphmodel without spatial reuse,this model is much more effective because it has a smaller value of AFD and alarger probability for finding a symmetric valid route. 相似文献
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Huayi Wu Xiaohua Jia Yanxiang He Chuanhe Huang 《International Journal of Communication Systems》2005,18(9):803-816
This paper investigates the issues of QoS routing in CDMA/TDMA ad hoc networks. Since the available bandwidth is very limited in ad hoc networks, a QoS request between two nodes will be blocked if there does not exist a path that can meet the QoS requirements, even though there is enough free bandwidth in the whole system. In this paper, we propose a new scheme of using multiple paths between two nodes as the route for a QoS call. The aggregate bandwidth of the multiple paths can meet the bandwidth requirement of the call and the delays of these paths are within the required bound of the call. We also propose three strategies by which to choose a set of paths as the route, namely, shortest path first (SPF), largest bandwidth first (LBF), and largest hop‐bandwidth first (LHBF). Extensive simulations have been conducted to evaluate the performance of the three strategies in comparison with a traditional single path routing algorithm. The simulation results show that the proposed multiple paths routing scheme significantly reduces the system blocking rates in various network environments, especially when the network load is heavy. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Chenn-Jung Huang Wei-Kuang Lai Sheng-Yu Hsiao Hao-Yu Liu Rui-Lin Luo 《International Journal of Wireless Information Networks》2004,11(3):131-146
In this paper, a routing protocol which utilizes the characteristics of Bluetooth technology is proposed for Bluetooth-based mobile ad hoc networks. The routing tables are maintained in the master devices and the routing zone radius for each table is adjusted dynamically by using evolving fuzzy neural networks. Observing there exists some useless routing packets which are helpless to build the routing path and increase the network loads in the existing ad hoc routing protocols, we selectively use multiple unicasts or one broadcast when the destination device is out of the routing zone radius coverage of the routing table. The simulation results show that the dynamic adjustment of the routing table size in each master device results in much less reply time of routing request, fewer request packets and useless packets compared with two representative protocols, Zone Routing Protocol and Dynamic Source Routing. 相似文献
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The Role of Network Topologies in the Optical Core of IP-over-WDM Networks with Static Wavelength Routing 总被引:3,自引:0,他引:3
Freire Mário M. Rodrigues Joel J.P.C. Coelho Rui M.F. 《Telecommunication Systems》2003,24(2-4):111-122
In this paper, we present a performance analysis of network topologies for the optical core of IP-over-WDM networks with static wavelength routing. The performance analysis is focused on regular degree four topologies, and, for comparison purposes, degree three topologies are also considered. It is shown that the increase of the nodal degree from three (degree three topology with smallest diameter) to four (degree four topology with smallest diameter) improves the network performance if a larger number of wavelengths per link is available. However, the influence of wavelength interchange on the nodal degree gain is small. The performance of regular degree four topologies with smallest diameter is also compared with the performance of mesh–torus topologies (which are also degree four topologies), and it is shown that the blocking probability of degree four topologies with smallest diameter is about two orders of magnitude lower than the blocking probability of mesh–torus topologies. It is also presented a performance comparison of WDM-based networks with nodal degrees ranging from two to five and it is shown that the increase of the nodal degree from two to three leads to high nodal degree gains, while de increase of the nodal degree from four to five leads to low nodal degree gains. These results show that degree three and degree four topologies are very attractive for use in the optical core of IP-over-WDM networks. 相似文献
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Rafael Caballero Mercedes González Flor M Guerrero Julián Molina Concepción Paralera 《European Journal of Operational Research》2007
In this work we present a multiobjective location routing problem and solve it with a multiobjective metaheuristic procedure. In this type of problem, we have to locate some plants within a set of possible locations to meet the demands of a number of clients with multiple objectives. This type of model is used to solve a problem with real data in the region of Andalusia (Spain). Thus, we study the location of two incineration plants for the disposal of solid animal waste from some preestablished locations in Andalusia, and design the routes to serve the different slaughterhouses in this region. This must be done while taking into account certain economic objectives (start-up, maintenance, and transport costs) and social objectives (social rejection by towns on the truck routes, maximum risk as an equity criterion, and the negative implications for towns close to the plant). 相似文献
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首先将无线传感器网络的路由问题转化成求解最小Steiner树问题,然后给出了求解无线传感器网络路由的蚁群优化算法,并对算法的收敛性进行了证明.最后对找到最优解后信息素值的变化进行了分析.即在限制信息素取值的条件下,当迭代次数充分大时,该算法能以任意接近于1的概率找到最优解,并且当最优解找到后,最优树边上的信息素单调增加,而最优解以外边上的信息素在有限步达到最小值. 相似文献