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1.
Recently, wireless networks have become one of the major development trends in computer network technology. Because there is no more need of the wired transmission medium, applications have thus diversified. One such growing field of wireless networks is the mobile ad‐hoc network (MANET). A MANET consists of mobile hosts (such as portable laptops, vehicles, etc.), and no fixed infrastructure is required. MANETs provide ease of self‐configuration and can extend coverage at a low cost. Numerous applications have therefore been proposed under this network environment for daily life use. Because MANETs nodes are capable of moving, MANET network topology changes frequently. Thus, the traditional routing protocols fail to fit such an environment. In this paper, we propose an efficient routing protocol for MANETs, which integrates the mathematical model of profit optimization (the Kelly formula) from the field of economics to cope with the routing problem caused by node mobility. Some numerical simulations have been conducted to evaluate the performance of the proposed method using the network simulator NS‐2. The results show that our proposed method outperforms conventional routing protocols in packet delivery ratio comparisons; and the average end‐to‐end delays are within a tolerable range. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

2.
One of the infrastructure-free networks is mobile ad hoc networks (MANETs) that are built with limited battery life using wireless mobile devices. This restricted battery capability in MANETs creates the necessity of considering the energy-awareness constraint in designing them. As routing protocols, the major aim of MANETs is to create the energy awareness in the network; it improves the network's lifetime through effectively utilizing the available restricted energy. Moreover, it creates some limitations like the mobility constraint, wireless link's sensitivity to environmental impacts, and restricted transmission range and residual energy of nodes that causes rapid modifications in the network topology and frequent link failure. By taking those problems, this paper plans to develop a new multipath routing protocol, where the hybrid optimization algorithm with the integration of cuckoo search optimization (CSO) and butterfly optimization algorithm (BOA) is proposed and named sensory modality-based cuckoo search butterfly optimization (SM-CSBO) for determining the optimal path between the source and destination. The main goal is to select the path with better link quality and more stable links to guarantee reliable data transmission. The multi-objective function is considered with the factors regarding distance, normalized energy, packet delivery ratio, and control overhead to develop an effective routing protocol in MANET. The proposed model of SM-CSBO algorithm has superior than 5.8%, 30.4%, 36.7%, and 39.3%, correspondingly maximized than PSO, SFO, CSO, and SFO algorithms while considering the number of nodes as 150. The simulation outcomes proved that it enhances network performance when compared with the other traditional protocols.  相似文献   

3.
In this paper, we present a new quality of service (QoS) routing protocol for mobile ad hoc networks (MANETs). Most of the existing routing protocols assume homogeneous nodes in MANETs, i.e., all nodes have the same communication capabilities and characteristics. However, in many ad hoc networks, nodes are not the same. Some nodes have longer transmission range, larger transmission bandwidth, and are more reliable and robust than other nodes. We take advantage of the non-homogeneous property to design more efficient QoS routing protocol. And node location information is used to aid routing. We also develop a new algorithm to calculate end-to-end bandwidth for a given path. Our QoS routing protocol contains end-to-end bandwidth calculation and bandwidth reservation. QoS route is discovered and setup only when it is needed. Extensive simulation studies demonstrate the good performance of the QoS routing protocol.  相似文献   

4.
Terrorist attacks have contributed significantly to using wireless technologies to identify concrete destruction survivors. A dynamic ad hoc mobile network (MANET) consists of wireless linked nodes, which route hop-by-hop without the support of a fixed infrastructure acquires information from trapped survivors. The energy efficiency that extends the lifespan of the network is an essential prerequisite of MANET. Researchers have suggested many strategies to accomplish this purpose and a cluster of these techniques in MANETs are used to provide an energy-efficient approach. In this paper we are proposing a red deer multi-objective constraint applied for an energy efficient QoS routing (RD-MOCER) algorithm to the number of clusters in an ad hoc network and the energy dispensing in nodes to provide an energy effective solution and to minimise network traffic. Intracluster and intercluster traffic is handled by the cluster heads in the proposed approach. The algorithm suggested takes account of mobile nodes' node degrees, transmitting capacity and battery power usage. This approach gives a variety of options at a time, the key benefit of which is that the ideal Pareto front results in these solutions. We correlate the findings with two other well-known methods of clustering; MOPSO and MOEAQ-based clustering with different results. We conduct detailed simulations to demonstrate that the solution proposed is an effective and stronger solution to clustering in ad hoc cell networks than the other two techniques.  相似文献   

5.
Mobile ad hoc networks (MANETs) are characterized by random, multi‐hop topologies that do not have a centralized coordinating entity or a fixed infrastructure that may change rapidly over time. In addition, mobile nodes operate with portable and finite power sources. In this work, we propose an energy‐efficient routing protocol for MANETs to minimize energy consumption and increase the network's consistency. Traditional works mainly focused on the shortest path‐based schemes to minimize energy, which might result into network failure because some nodes might exhaust fast as they are used repetitively, while some other nodes might not be used at all. This can lead to energy imbalance and to network life reduction. We propose an energy‐efficient ad hoc on‐demand routing protocol that balances energy load among nodes so that a minimum energy level is maintained among nodes and the network life increases. We focused on increasing the network longevity by distributing energy consumption in the network. We also compared the simulation results with a popular existing on‐demand routing protocol in this area, AODV, to establish the superiority of our approach. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

6.
LSCR:一种Mobile Ad hoc网络链路状态分组路由算法   总被引:4,自引:0,他引:4       下载免费PDF全文
熊焰  苗付友  王行甫 《电子学报》2003,31(5):645-648
本文提出了一种Mobile Ad hoc网络(Manet)链路状态分组路由算法(Link State-hased Cluster Routing Algo-rithm-LSCR),该算法对Manet节点进行动态分组,每一组选举出一个具有最大度数的头结点(CH-Cluster Header),该cH负责本组信息的管理、组内结点与组外结点之间的通信以及与其他组的CH之间交换链路状态信息等工作.本算法将改进的链路状态协议与分组路由协议有机结合,有效提高了Manet网络的路由效率.分析和实验结果表明,这种算法具有路由收敛速度快、维护成本相对较低,数据包发送成功率高,发送等待时间短等特点。  相似文献   

7.
Mobile ad hoc networks are collections of mobile nodes that can dynamically form temporary networks without the need for pre-existing network infrastructure or centralized administration. These nodes can be arbitrarily located and can move freely at any given time. Hence, the network topology can change rapidly and unpredictably. Because wireless link capacities are usually limited, congestion is possible in MANETs. Hence, balancing the load in a MANET is important since nodes with high loads will deplete their batteries quickly, thereby increasing the probability of disconnecting or partitioning the network. This article discusses the various load metrics and summarizes the principles behind several existing load balanced ad hoc routing protocols. Finally, a qualitative comparison of the various load metrics and load balanced routing protocols is presented.  相似文献   

8.
A novel scheme is presented to integrate mobile ad hoc networks (MANETs) with the lnternet and support mobility across wireless local area networks (WLANs) and MANETs. The mobile nodes, connected as a MANET, employ the optimize d link state routing (OLSR) protocol for routing within the MANET. Mobility management across WLANs and MANETs is achieved through the hierarchical mobile IPv6 (HMIPv6) protocol. The performance is evaluated on a HMIPv6 based test-bed composed of WLANs and MANETs. The efficiency gain obtained from using HMIPv6 in such a hybrid network is investigated. The investigation result shows that the use of HMIPv6 can achieve up to 27% gain on reducing the handoff latency when a mobile roams within a domain. Concerning the reduction of the signaling load on the lnternet, the use of HMIPv6 can achieve at least a 54% gain and converges to 69%.  相似文献   

9.
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   

10.
A mobile ad hoc network (MANET) is an autonomous collection of mobile nodes that communicate over relatively bandwidth‐constrained wireless links. MANETs need efficient algorithms to determine network connectivity, link scheduling, and routing. An important issue in network routing for MANETs is to conserve power while still achieve a high packet success rate. Traditional MANET routing protocols do not count for such concern. They all assume working with unlimited power reservoirs. Several ideas have been proposed for adding power‐awareness capabilities to ad hoc networks. Most of these proposals tackle the issue by either proposing new power‐aware routing protocols or modifying existing routing protocols through the deployment of power information as cost functions. None of them deal with counter‐measures that ought to be taken when nodes suffer from low power reserves and are subject to shut down in mid of normal network operations. In this paper, power‐awareness is added to a well‐known traditional routing protocol, the ad hoc on‐demand distance vector (AODV) routing protocol. The original algorithm is modified to deal with situations in which nodes experience low power reserves. Two schemes are proposed and compared with the original protocol using different performance metrics such as average end‐to‐end delays, transmission success rates, and throughputs. These schemes provide capabilities for AODV to deal with situations in which operating nodes have almost consumed their power reserves. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

11.
Mobile ad hoc networks (MANETs) are becoming an emerging technology that offer several advantages to users in terms of cost and ease of use. A MANET is a collection of mobile nodes connected by wireless links that form a temporary network topology that operates without a base station and centralized administration. Routing is a method through which information is forwarded from a transmitter to a specific recipient. Routing is a strategy that guarantees, at any time, the connection between any two nodes in a network. In this work, we propose a novel routing protocol inspired by the cuckoo search method. Our routing protocol is implemented using Network simulator 2. We chose Random WayPoint model as our mobility model. To validate our work, we opted for the comparison with the routing protocol ad hoc on-demand distance vector, destination sequence distance vector and the bio-inspired routing protocol AntHocNet in terms of the quality of service parameters: packet delivery ratio and end-to-end delay (E2ED).  相似文献   

12.
One of the important aspects of a mobile ad hoc network (MANET) is the limitation of the amount of available energy and the network lifetime. The tremendous amount of using mobile nodes in wireless communication medium makes energy efficiency a fundamental requirement for MANETs. In this paper, we propose a novel energy aware clustering algorithm for the optimized link state routing (OLSR) routing protocol. This algorithm takes into account the node density and mobility and gives major improvements regarding the number of elected cluster heads. Our objective is to elect a reasonable number of cluster heads that will serve for hierarchical routing based on OLSR. The proposed algorithm aims to increase the network lifetime by considering the ad hoc residual energy while taking routing decisions. It also optimizes the delay of carried flows by adopting a selective forwarding approach based on a hierarchical routing model.  相似文献   

13.
A new cross-layer routing protocol, named Dynamic Packet Guidance (DPG), is introduced for Mobile Ad hoc Networks (MANETs). Simulation results show that DPG is quite useful for usage in dense networks of mobile nodes, with medium-to-high speeds, and low-to-medium load. In these scenarios, DPG provides a superior performance compared to several well-known ad hoc routing protocols. The low end-to-end delay and smaller overhead that DPG achieves in such scenarios positively impacts the scalability of MANETs and reduces the energy requirements of nodes in such networks. DPG also shows immunity to failing nodes, as it operates consistently almost independently of failing nodes up to a certain ratio.  相似文献   

14.
SMORT: Scalable multipath on-demand routing for mobile ad hoc networks   总被引:3,自引:0,他引:3  
L.  S.V.   《Ad hoc Networks》2007,5(2):162-188
Increasing popularity and availability of portable wireless devices, which constitute mobile ad hoc networks, calls for scalable ad hoc routing protocols. On-demand routing protocols adapt well with dynamic topologies of ad hoc networks, because of their lower control overhead and quick response to route breaks. But, as the size of the network increases, these protocols cease to perform due to large routing overhead generated while repairing route breaks. We propose a multipath on-demand routing protocol (SMORT), which reduces the routing overhead incurred in recovering from route breaks, by using secondary paths. SMORT computes fail-safe multiple paths, which provide all the intermediate nodes on the primary path with multiple routes (if exists) to destination. Exhaustive simulations using GloMoSim with large networks (2000 nodes) confirm that SMORT is scalable, and performs better even at higher mobility and traffic loads, when compared to the disjoint multipath routing protocol (DMRP) and ad hoc on-demand distance vector (AODV) routing protocol.  相似文献   

15.
A mobile ad‐hoc network (MANET) is a collection of autonomous nodes that communicate with each other by forming a multi‐hop radio network. Routing protocols in MANETs define how routes between source and destination nodes are established and maintained. Multicast routing provides a bandwidth‐efficient means for supporting group‐oriented applications. The increasing demand for such applications coupled with the inherent characteristics of MANETs (e.g., lack of infrastructure and node mobility) have made secure multicast routing a crucial yet challenging issue. Recently, several multicast routing protocols (MRP) have been proposed in MANETs. Depending on whether security is built‐in or added, MRP can be classified into two types: secure and security‐enhanced routing protocols, respectively. This paper presents a survey on secure and security‐enhanced MRP along with their security techniques and the types of attacks they can confront. A detailed comparison for the capability of the various routing protocols against some known attacks is also presented and analyzed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

16.
Mobile Ad Hoc Networks (MANETs) have evolved in the last years into standards in the communication world. By definition, they do not need any network infrastructure to facilitate communication between participating nodes. Therefore, MANETs are dealing with new challenges in the context of ad hoc routing. Simulation techniques are one of the fundamental methodologies to support the protocol engineering process, especially in the early stages of ad hoc network protocol design. In this paper, we set out common criteria that may serve as guidelines for meaningful simulative evaluations of ad hoc routing protocols. We present typical and necessary measures for ad hoc routing in general and MANET routing in particular. As a case study, we demonstrate a comprehensive performance evaluation of the Dynamic MANET On Demand (DYMO) routing protocol using a model we implemented for the popular OMNeT+ + discrete event simulation environment.  相似文献   

17.
Power-aware routing protocols in ad hoc wireless networks   总被引:5,自引:0,他引:5  
An ad hoc wireless network has no fixed networking infrastructure. It consists of multiple, possibly mobile, nodes that maintain network connectivity through wireless communications. Such a network has practical applications in areas where it may not be economically practical or physically possible to provide a conventional networking infrastructure. The nodes in an ad hoc wireless network are typically powered by batteries with a limited energy supply. One of the most important and challenging issues in ad hoc wireless networks is how to conserve energy, maximizing the lifetime of its nodes and thus of the network itself. Since routing is an essential function in these networks, developing power-aware routing protocols for ad hoc wireless networks has been an intensive research area in recent years. As a result, many power-aware routing protocols have been proposed from a variety of perspectives. This article surveys the current state of power-aware routing protocols in ad hoc wireless networks.  相似文献   

18.
Frequent changes in network topologies caused by mobility in mobile ad hoc networks (MANETs) impose great challenges to designing routing schemes for such networks. Various routing schemes each aiming at particular type of MANET (e.g., flat or clustered MANETs) with different mobility degrees (e.g., low, medium, and high mobility) have been proposed in the literature. However, since a mobile node should not be limited to operate in a particular MANET assumed by a routing scheme, an important issue is how to enable a mobile node to achieve routing performance as high as possible when it roams across different types of MANETs. To handle this issue, a quantity that can predict the link status for a time period in the future with the consideration of mobility is required. In this paper, we discuss such a quantity and investigate how well this quantity can be used by the link caching scheme in the dynamic source routing protocol to provide the adaptability to variable topologies caused by mobility through computer simulation in NS-2.  相似文献   

19.
As mobile ad hoc networks (MANETs) are emerging as important components in critical and large-scale applications, it is crucial to develop MANET routing mechanisms with provably low complexity. In this paper, we give a tutorial overview of the efficient use of elementary node clustering and route request broadcast mechanisms for low-complexity MANET routing. We explain these mechanisms with illustrative examples and discuss their theoretical performance characteristics. We demonstrate that node clustering with constant density and route request broadcasting with a doubling radius technique over the network of cluster leaders can be employed for MANET routing with theoretically proven low complexity. Moreover, we contrast these efficient elementary clustering and route request broadcast mechanisms with clustering and route information accumulation mechanisms in the widely studied AODV and DSR routing protocols and discuss the implications of these various mechanisms for scalable MANET routing.  相似文献   

20.
Adhoc是一组无线移动主机组成的一个无需基础设施或集中管理设备的临时网络。网络拓扑易变、带宽、能源有限是其主要特点。文章主要介绍Adhoc网络和组网关键技术——路由协议,并对现在具有代表性的协议性能进行了比较分析,指出了下一步的研究方向。  相似文献   

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