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1.
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   

2.
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   

3.
Many protocols, services, and electrical devices with built-in sensors have been developed in response to the rapid expansion of the Internet of Things. Mobile ad hoc networks (MANETs) consist of a collection of autonomous mobile nodes that can form an ad hoc network in the absence of any pre-existing infrastructure. System performance may suffer due to the changeable topology of MANETs. Since most mobile hosts operate on limited battery power, energy consumption poses the biggest challenge for MANETs. Both network lifetime and throughput improve when energy usage is reduced. However, existing approaches perform poorly in terms of energy efficiency. Scalability becomes a significant issue in large-scale networks as they grow, leading to overhead associated with routing updates and maintenance that can become unmanageable. This article employs a MANET routing protocol combined with an energy conservation strategy. The clustering hierarchy is used in MANETs to maximize the network's lifespan, considering its limited energy resources. In the MANET communication process, the cluster head (CH) is selected using Fire Hawk Optimization (FHO). When choosing nodes to act as a cluster for an extended period, CH election factors in connectivity, mobility, and remaining energy. This process is achieved using an optimized version of the Ad hoc On-Demand Distance Vector (AODV) routing protocol, utilizing Improved Chicken Swarm Optimization (ICSO). In comparison to existing protocols and optimization techniques, the proposed method offers an extended network lifespan ranging from 90 to 160 h and reduced energy consumption of 80 to 110 J, as indicated by the implementation results.  相似文献   

4.
Following recent advances in the performance of ad hoc networks, the limited life of batteries in mobile devices poses a bottleneck in their development. Consequently, how to minimize power consumption in the Medium Access Control (MAC) layer of ad hoc networks is an essential issue. The power‐saving mode (PSM) of IEEE 802.11 involves the Timing Synchronization Function to reduce power consumption for single‐hop mobile ad hoc networks (MANETs). However, the IEEE 802.11 PSM is known to result in unnecessary energy consumption as well as the problems of overheating and back‐off time delay. Hence, this study presents an efficient power‐saving MAC protocol, called p‐MANET, based on a Multi‐hop Time Synchronization Protocol, which involves a hibernation mechanism, a beacon inhibition mechanism, and a low‐latency next‐hop selection mechanism for general‐purpose multi‐hop MANETs. The main purposes of the p‐MANET protocol are to reduce significantly the power consumption and the transmission latency. In the hibernation mechanism, each p‐MANET node needs only to wake up during one out of every N beacon interval, where N is the number of beacon intervals in a cycle. Thus, efficient power consumption is achieved. Furthermore, a beacon inhibition mechanism is proposed to prevent the beacon storm problem that is caused by synchronization and neighbor discovery messages. Finally, the low‐latency next‐hop selection mechanism is designed to yield low transmission latency. Each p‐MANET node is aware of the active beacon intervals of its neighbors by using a hash function, such that it can easily forward packets to a neighbor in active mode or with the least remaining time to wake up. As a consequence, upper‐layer routing protocols can cooperate with p‐MANET to select the next‐hop neighbor with the best forwarding delay. To verify the proposed design and demonstrate the favorable performance of the proposed p‐MANET, we present the theoretical analysis related to p‐MANET and also perform experimental simulations. The numerical results show that p‐MANET reduces power consumption and routing latency and performs well in extending lifetime with a small neighbor discovery time. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

5.
Connecting wired and wireless networks, and particularly mobile wireless ad hoc networks (MANETs) and the global Internet, is attractive in real‐world scenarios due to its usefulness and praticality. Because of the various architectural mismatches between the Internet and MANETs with regard to their communication topology, routing protocols, and operation, it is necessary to introduce a hybrid interface capable of connecting to the Internet using Mobile IP protocol and to MANETs owing to an ad hoc routing protocol. Specifically, the approaches available in the literature have introduced updated versions of Mobile IP agents or access points at the edge of the Internet to help MANET nodes get multi‐hop wireless Internet access. The main differences in the existing approaches concern the type of ad hoc routing protocol as well as the switching algorithm used by MANET nodes to change their current Mobile IP agents based on specific switching criteria. This paper surveys a variety of approaches to providing multi‐hop wireless Internet access to MANET nodes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

6.
Routing security in wireless ad hoc networks   总被引:8,自引:0,他引:8  
A mobile ad hoc network consists of a collection of wireless mobile nodes that are capable of communicating with each other without the use of a network infrastructure or any centralized administration. MANET is an emerging research area with practical applications. However, wireless MANET is particularly vulnerable due to its fundamental characteristics, such as open medium, dynamic topology, distributed cooperation, and constrained capability. Routing plays an important role in the security of the entire network. In general, routing security in wireless MANETs appears to be a problem that is not trivial to solve. In this article we study the routing security issues of MANETs, and analyze in detail one type of attack-the "black hole" problem-that can easily be employed against the MANETs. We also propose a solution for the black hole problem for ad hoc on-demand distance vector routing protocol.  相似文献   

7.
Energy is an important issue in mobile ad hoc networks (MANETs), and different energy‐aware routing mechanisms have been proposed to minimize the energy consumption in MANETs. Most of the energy‐aware routing schemes reported in the literature have considered only the residual battery capacity as the cost metric in computing a path. In this paper, we have proposed, an energy‐aware routing technique which considers the following parameters: (i) a cost metric, which is a function of residual battery power and energy consumption rate of participating nodes in path computation; (ii) a variable transmission power technique for transmitting data packets; and (iii) To minimize the over‐utilization of participating nodes, a limit is set on the number of paths that can be established to a destination through a participating node. The proposed scheme is simulated using Qualnet 4.5 simulator, and compared with Ad hoc On‐Demand Distance Vector (AODV) and Lifetime Enhancement Routing (LER). We observed that the proposed scheme performs better in terms of network lifetime and energy consumption. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

8.

A mobile ad hoc network (MANET) is a collection of wireless mobile nodes that can communicate without a central controller or fixed infrastructure. Due to node mobility, designing a routing protocol to provide an efficient and suitable method to route the data with less energy consumption, packet drop and to prolong the network lifetime has become a challenging issue in MANETs. In MANETs, reducing energy consumption and packet loss involves congestion control and load balancing techniques. Thus, this paper introduces an efficient routing technique called the multipath load balancing technique for congestion control (MLBCC) in MANETs to efficiently balance the load among multiple paths by reducing the congestion. MLBCC introduces a congestion control mechanism and a load balancing mechanism during the data transmission process. The congestion control mechanism detects the congestion by using an arrival rate and an outgoing rate at a particular time interval T. The load balancing mechanism selects a gateway node by using the link cost and the path cost to efficiently distribute the load by selecting the most desirable paths. For an efficient flow of distribution, a node availability degree standard deviation parameter is introduced. Simulation results of MLBCC show the performance improvements in terms of the control overhead, packet delivery ratio, average delay and packet drop ratio in comparison with Fibonacci sequence multipath load balancing, stable backbone-based multipath routing protocol and ad hoc on demand multipath distance vector routing. In addition, the results show that MLBCC efficiently balances the load of the nodes in the network.

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9.
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   

10.

Worldwide Interoperability for Microwave Access (Wimax) is power station through which mobile network, commonly known as A Mobile Ad-hoc Network (MANET) is used by the people. A MANET can be described as an infrastructure-less and self-configure network with autonomous nodes. Participated nodes in MANETs move through the network constantly causing frequent topology changes. Designing suitable routing protocols to handle the dynamic topology changes in MANETs can enhance the performance of the network. In this regard, this paper proposes four algorithms for the routing problem in MANETs. First, we propose a new method called Classical Logic-based Routing Algorithm for the routing problem in MANETs. Second is a routing algorithm named Fuzzy Logic-based Routing Algorithm (FLRA). Third, a Reinforcement Learning-based Routing Algorithm is proposed to construct optimal paths in MANETs. Finally, a fuzzy logic-based method is accompanied with reinforcement learning to mitigate existing problems in FLRA. This algorithm is called Reinforcement Learning and Fuzzy Logic-based (RLFLRA) Routing Algorithm. Our proposed approaches can be deployed in dynamic environments and take four important fuzzy variables such as available bandwidth, residual energy, mobility speed, and hop-count into consideration. Simulation results depict that learning process has a great impact on network performance and RLFLRA outperforms other proposed algorithms in terms of throughput, route discovery time, packet delivery ratio, network access delay, and hop-count.

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11.
A mobile ad hoc network (MANET) is a self-configurable network connected by wireless links. This type of network is only suitable for provisional communication links as it is infrastructure-less and there is no centralized control. Providing QoS and security aware routing is a challenging task in this type of network due to dynamic topology and limited resources. The main purpose of secure and trust based on-demand multipath routing is to find trust based secure route from source to destination which will satisfy two or more end to end QoS constraints. In this paper, the standard ad hoc on-demand multi-path distance vector protocol is extended as the base routing protocol to evaluate this model. The proposed mesh based multipath routing scheme to discover all possible secure paths using secure adjacent position trust verification protocol and better link optimal path find by the Dolphin Echolocation Algorithm for efficient communication in MANET. The performance analysis and numerical results show that our proposed routing protocol produces better packet delivery ratio, reduced packet delay, reduced overheads and provide security against vulnerabilities and attacks.  相似文献   

12.
Mobile-Ad-Hoc-Networks (MANETs) are self-configuring networks of mobile nodes, which communicate through wireless links. The main issues in MANETs include the mobility of the network nodes, the scarcity of computational, bandwidth and energy resources. Thus, MANET routing protocols should explicitly consider network changes and node changes into the algorithm design. MANETs are particularly suited to guarantee connectivity in disaster relief scenarios, which are often impaired by the absence of network infrastructures. Moreover, such scenarios entail strict requirements on the lifetime of the device batteries and on the reactivity to possibly frequent link failures. This work proposes a proactive routing protocol, named MQ-Routing, aimed at maximizing the minimum node lifetime and at rapidly adapting to network topology changes. The proposed protocol modifies the Q-Routing algorithm, developed via Reinforcement Learning (RL) techniques, by introducing: (i) new metrics, which account for the paths availability and the energy in the path nodes, and which are dynamically combined and adapted to the changing network topologies and resources; (ii) a fully proactive approach to assure the protocol usage and reactivity in mobile scenarios. Extensive simulations validate the effectiveness of the proposed protocol, through comparisons with both the standard Q-Routing and the Optimized Link State Routing (OLSR) protocols.  相似文献   

13.
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   

14.
Multicasting is an effective way to provide group communication. In mobile ad hoc networks (MANETs), multicasting can support a wide variety of applications that are characterized by a close degree of collaboration. Since MANETs exhibit severe resource constraints such as battery power, limited bandwidth, dynamic network topology and lack of centralized administration, multicasting in MANETs become complex. The existing multicast routing protocols concentrate more on quality of service parameters like end‐to‐end delay, jitter, bandwidth and power. They do not stress on the scalability factor of the multicast. In this paper, we address the problem of multicast scalability and propose an efficient scalable multicast routing protocol called ‘Power Aware Scalable Multicast Routing Protocol (PASMRP)’ for MANETs. PASMRP uses the concept of class of service with three priority levels and local re‐routing to provide scalability. The protocol also ensures fair utilization of the resources among the nodes through re‐routing and hence the lifetime of the network is increased. The protocol has been simulated and the results show that PASMRP has better scalability and enhanced lifetime than the existing multicast routing protocols. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

15.
How to efficiently build routes among nodes is increasing important for mobile ad hoc networks (MANETs). This paper puts forward an interference aware routing protocol called Interference aware cross layer routing protocol (IA-CLR) for MANETs based on the IEEE 802.11 medium access layer (MAC). By defining the node's sending and receiving capabilities, IA-CLR can indicate the interference strength of the link in a real and comprehensive way. Further more, in order to choose the route with minimum bottleneck link interference, a new routing metric is proposed by combining the MAC layer and the network layer for cross layer design. Simulation results show that IA-CLR can significantly improve the performances of network such as the average end-to-end delay, the packets loss ratio and the throughput.  相似文献   

16.
In recent research, link stability is getting tremendous attention in mobile adhoc networks (MANETs), because of several impediments that occur in a reliable and robust network. Link stability metric is used to improve network performance in terms of end-to-end delay, data success delivery ratio (DSDR) and available route time (ART). Energy consumption, bandwidth and communication delay of major concern in ad hoc networks. A high mobility of MANET nodes reduces the reliability of network communication. In a dynamic networks, high mobility of the nodes makes it very difficult to predict the dynamic routing topology and hence cause route/link failures. Multicast in MANETs is an emerging trend that effectively improves the performance while lowering the energy consumption and bandwidth usage. Multicast routing protocol transmits a packet to multicast a group at a given time instant to achieve a better utilization of resources. In this paper, node mobility is considered to map better their movement in the network. So, the links with long active duration time can be identified as a stable link for route construction. Variation in signal strength is used to identify whether the direction of the node is towards or away from estimating node. We consider signal strength as QoS metric to calculate link stability for route construction. Efforts are made to identify the link with highly probable longer lifetime as the best suitable link between two consecutive nodes. We predict the movement time of nodes that define the route path to the node destination. Exata/cyber simulator is used for network simulation. The simulation results of the proposed routing protocol are compared with on-demand multicast routing protocol and E-ODMRP, which works on minimum hop count path. Analysis of our simulation results has shown improvement of various routing performance metrics such as DSDR, ART, routing overhead and packet drop ratio.  相似文献   

17.
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   

18.
This paper compares ad hoc on‐demand distance vector (AODV), dynamic source routing (DSR) and wireless routing protocol (WRP) for MANETs to distance vector protocol to better understand the major characteristics of the three routing protocols, using a parallel discrete event‐driven simulator, GloMoSim. MANET (mobile ad hoc network) is a multi‐hop wireless network without a fixed infrastructure. Following are some of our key findings: (1) AODV is most sensitive to changes in traffic load in the messaging overhead for routing. The number of control packets generated by AODV became 36 times larger when the traffic load was increased. For distance vector, WRP and DSR, their increase was approximately 1.3 times, 1.1 times and 7.6 times, respectively. (2) Two advantages common in the three MANET routing protocols compared to classical distance vector protocol were identified to be scalability for node mobility in end‐to‐end delay and scalability for node density in messaging overhead. (3) WRP resulted in the shortest delay and highest packet delivery rate, implying that WRP will be the best for real‐time applications in the four protocols compared. WRP demonstrated the best traffic scalability; control overhead will not increase much when traffic load increases. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

19.
Mobile ad-hoc network (MANET) is a category of ad-hoc network that can be reconfigurable its network. MANETS are self-organized networks, that can use the wireless links to connect various networks via mobile nodes: but it consumes more energy and it also has routing problems. This is the major drawback of being connected with the MANET technology. Therefore, this study proposes a new protocol as deep Q-learning network optimized with chaotic bat swarm optimization algorithm (CBS)-based optimized link state routing (OLSR) (CBS-OLSR) for MANET. This protocol reduces MANET energy usage and adopts OLSR multi-point relay (MPR) technology. MANET's OLSR and the CBS algorithm utilize a similar method to locate the best optimum path from source to destination node. By embedding the new improved deep Q-learning and OLSR algorithms, both are used for optimizing the MPR sets selection, it can efficiently diminish the energy consumption in the network topology, but automatically increase the lifespan of the network. It also enhances the package delivery ratio and decreases end-to-end delay. The experimental outcomes prove that the proposed protocol is reliable and proficient that is appropriate for numerous MANET applications.  相似文献   

20.
Mobile ad hoc networks (MANETs) are characterized by multiple entities, a frequently changing network topology and the need for efficient dynamic routing protocols. In MANETs, nodes are usually powered by batteries. Power control is tightly coupled with both the physical and medium access layers (MACs). However, if we increase the transmission power, at the same time we increase the interference to other nodes which diminish the transport capacity of wireless systems. Thus, the routing protocols based on hop count metric suffer from performance degradation when they operate over MANET. Routing in ad hoc wireless networks is not only a problem of finding a route with shortest length, but it is also a problem of finding a stable and good quality communication route in order to avoid any unnecessary packet loss. Cross-layer design of ad hoc wireless networks has been receiving increasing attention recently. Part of these researches suggests that routing should take into account physical layer characteristics. The goal of this paper is to improve the routing reliability in MANET and to reduce power consumption through cross-layer approach among physical, MAC and network layers. The proposed cross-layer approach is based on signal to interference plus noise ratio (SINR) and received signal strength indication (RSSI) coming from the physical layer. This solution performs in one hand the ad hoc on-demand distance vector routing protocol by choosing reliable routes with less interferences using SINR metric and in another hand; it permits to reduce the power transmission when sending the data packets by using RSSI metric.  相似文献   

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