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1.
A Minimizing Intermediate Multicast Routing protocol (MIMR) is proposed for dynamic multi-hop ad hoc networks. In MIMR, multicast sessions are created and released only by source nodes. In each multicast session process, the source node keeps a list of intermediate nodes and destinations, which is encapsulated into the packet header when the source node sends a multicast packet. Nodes receiving multicast packets decide to accept or forward the packet according to the list. Depending on topology matrix maintained by unicast routing, the shortest virtual hierarchy routing tree is constructed by improved Dijkstra algorithm. MIMR can achieve the minimum number of intermediate nodes, which are computed through the tree. No control packet is transmitted in the process of multicast session. Load of the network is largely decreased. Experimental result shows that MIMR is flexible and robust for dynamic ad hoc networks.  相似文献   

2.
Active routing for ad hoc networks   总被引:1,自引:0,他引:1  
Ad hoc networks are wireless multihop networks whose highly volatile topology makes the design and operation of a standard routing protocol hard. With an active networking approach, one can define and deploy routing logic at runtime in order to adapt to special circumstances and requirements. We have implemented several active ad hoc routing protocols that configure the forwarding behavior of mobile nodes, allowing data packets to be efficiently routed between any two nodes of the wireless network. Isolating a simple forwarding layer in terms of both implementation and performance enables us to stream delay-sensitive audio data over the ad hoc network. In the control plane, active packets permanently monitor the connectivity and setup, and modify the routing state  相似文献   

3.
This paper presents a comprehensive study of the performance of routing protocols in distributed vehicular networks. We propose a novel and efficient routing protocol, namely cross‐layer, weighted, position‐based routing, which considers link quality, mobility and utilisation of nodes in a cross layer manner to make effective position‐based forwarding decisions. An analytic hierarchy process approach is utilised to combine multiple decision criteria into a single weighting function and to perform a comparative evaluation of the effects of aforementioned criteria on forwarding decisions. Comprehensive simulations are performed in realistic representative urban scenarios with synthetic and real traffic. Insights on the effect of different communication and mobility parameters are obtained. The results demonstrate that the proposed protocol outperforms existing routing protocols for vehicular ad hoc networks, including European Telecommunications Standards Institute (ETSI's) proposed greedy routing protocol, greedy traffic aware routing protocol and advanced greedy forwarding in terms of combined packet delivery ratio, end‐to‐end delay and overhead. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

4.
In autonomous mobile ad hoc networks, nodes belong to different authorities and pursue different goals; therefore, cooperation among them cannot be taken for granted. Meanwhile, some nodes may be malicious, whose objective is to damage the network. In this paper, we present a joint analysis of cooperation stimulation and security in autonomous mobile ad hoc networks under a game theoretic framework. We first investigate a simple yet illuminating two-player packet forwarding game and derive the optimal and cheat-proof packet forwarding strategies. We then investigate the secure routing and packet forwarding game for autonomous ad hoc networks in noisy and hostile environments and derive a set of reputation-based cheat-proof and attack-resistant cooperation stimulation strategies. When analyzing the cooperation strategies, besides Nash equilibrium, other optimality criteria, such as Pareto optimality, subgame perfection, fairness, and cheat-proofing, have also been considered. Both analysis and simulation studies have shown that the proposed strategies can effectively stimulate cooperation among selfish nodes in autonomous mobile ad hoc networks under noise and attacks, and the damage that can be caused by attackers is bounded and limited  相似文献   

5.
Existing routing and broadcasting protocols for ad hoc networks assume an ideal physical layer model. We apply the log-normal shadow fading model to represent a realistic physical layer and use the probability p(x) for receiving a packet successfully as a function of distance x between two nodes. We define the transmission radius R as the distance at which p(R)=0.5. We propose a medium access control layer protocol, where receiver node acknowledges packet to sender node u times, where u*p(x)/spl ap/1. We derived an approximation for p(x) to reduce computation time. It can be used as the weight in the optimal shortest hop count routing scheme. We then study the optimal packet forwarding distance to minimize the hop count, and show that it is approximately 0.73R (for power attenuation degree 2). A hop count optimal, greedy, localized routing algorithm [referred as ideal hop count routing (IHCR)] for ad hoc wireless networks is then presented. We present another algorithm called expected progress routing with acknowledgment (referred as aEPR) for ad hoc wireless networks. Two variants of aEPR algorithm, namely, aEPR-1 and aEPR-u are also presented. Next, we propose projection progress scheme, and its two variants, 1-Projection and u-Projection. Iterative versions of aEPR and projection progress attempt to improve their performance. We then propose tR-greedy routing scheme, where packet is forwarded to neighbor closest to destination, among neighbors that are within distance tR. All described schemes are implemented, and their performances are evaluated and compared.  相似文献   

6.
Mobile ad hoc networks rely on the cooperation of nodes for routing and forwarding. However, individual nodes may not always be willing to cooperate. In order thus to stimulate cooperation in ad hoc networks, several incentive mechanisms have been developed. In this paper we propose a new hybrid incentive mechanism, called ICARUS, which is an extension of DARWIN, a well-known reputation-based mechanism, combining advantages of both reputation-based and credit-based mechanisms. The objective of ICARUS is to detect and punish selfish nodes efficiently and at the same time motivate nodes to cooperate by rewarding the packet forwarding. Furthermore, ICARUS ensures fairness for distant nodes and prevents selfish nodes from corrupting the system using false information. The proposed scheme’s performance is tested through extended series of simulations and is compared with DARWIN. We show that ICARUS detects and isolates selfish nodes much faster, while at the same time improves the Quality of Service (QoS) received by non-selfish nodes, including distant ones.  相似文献   

7.
Geographic ad hoc networks use position information for routing. They often utilize stateless greedy forwarding and require the use of recovery algorithms when the greedy approach fails. We propose a novel idea based on virtual repositioning of nodes that allows to increase the efficiency of greedy routing and significantly increase the success of the recovery algorithm based on local information alone. We explain the problem of predicting dead ends which the greedy algorithm may reach and bypassing voids in the network, and introduce NEAR, node elevation ad-hoc routing, a solution that incorporates both virtual positioning and routing algorithms that improve performance in ad-hoc networks containing voids. We demonstrate by simulations the advantages of our algorithm over other geographic ad-hoc routing solutions.  相似文献   

8.
Scalable geographic routing algorithms for wireless ad hoc networks   总被引:1,自引:0,他引:1  
Frey  H. 《IEEE network》2004,18(4):18-22
The design of efficient routing protocols for dynamical changing network topologies is a crucial part of building power-efficient and scalable ad hoc wireless networks. If position information is available due to GPS or some kind of relative positioning technique, a promising approach is given by geographic routing algorithms, where each forwarding decision is based on the positions of current, destination, and possible candidate nodes in vicinity only. About 15 years ago heuristic greedy algorithms were proposed, which in order to provide freedom from loops might fail even if there is a path from source to destination. In recent years planar graph traversal has been investigated as one possible strategy to recover from such greedy routing failures. This article provides a tutorial for this class of geographic routing algorithms, and discusses recent improvements to both greedy forwarding and routing in planar graphs.  相似文献   

9.
We consider the problem of localized energy aware routing in mobile ad hoc networks. In localized routing algorithms, each node forwards a message based on the position of itself, its neighbors and the destination. The objective of energy aware routing algorithms is to minimize the total power for routing a message from source to destination or to maximize the total number of routing tasks that a node can perform before its battery power depletes. In this paper we propose new localized energy aware routing algorithms called OLEAR. The algorithms have very high packet delivery rate with low packet forwarding and battery power consumption. In addition, they ensure good energy distribution among the nodes. Finally, packets reach the destination using smaller number of hops. All these properties make our algorithm suitable for routing in any energy constrained environment. We compare the performance of our algorithms with other existing energy and non‐energy aware localized algorithms. Simulation experiments show that our algorithms present comparable energy consumption and distribution to other energy aware algorithms and better packet delivery rate. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

10.
Position-based routing in ad hoc networks   总被引:15,自引:0,他引:15  
The availability of small, inexpensive low-power GPS receivers and techniques for finding relative coordinates based on signal strengths, and the need for the design of power-efficient and scalable networks provided justification for applying position-based routing methods in ad hoc networks. A number of such algorithms were developed previously. This tutorial will concentrate on schemes that are loop-free, localized, and follow a single-path strategy, which are desirable characteristics for scalable routing protocols. Routing protocols have two modes: greedy mode (when the forwarding node is able to advance the message toward the destination) and recovery mode (applied until return to greedy mode is possible). We discuss them separately. Methods also differ in metrics used (hop count, power, cost, congestion, etc.), and in past traffic memorization at nodes (memoryless or memorizing past traffic). Salient properties to be emphasized in this review are guaranteed delivery, scalability, and robustness  相似文献   

11.
Venkata C.  Mukesh   《Ad hoc Networks》2007,5(7):1113-1128
We present a self-healing On-demand Geographic Path Routing Protocol (OGPR) for mobile ad-hoc networks. OGPR is an efficient, stateless, and scalable routing protocol that inherits the best of the three well-known techniques for routing in ad-hoc networks, viz., greedy forwarding, reactive route discovery, and source routing. In OGPR protocol, source nodes utilize the geographic-topology information obtained during the location request phase to establish geographic paths to their respective destinations. Geographic paths decouple node ID’s from the paths and are immune to changes in the network topology. Further, they help nodes avoid dead-ends due to greedy forwarding. To utilize geographic paths even in sparser networks, OGPR uses a path-healing mechanism that helps geographic paths adapt according to the network topology. We present extensions to OGPR protocol to cope with networks containing unidirectional links. Further, we present results from an extensive simulation study using GloMoSim. Simulation results show that OGPR achieves higher percentage packet delivery and lower control overhead, compared to a combination of GPSR+GLS protocols, AODV, and DSR under a wide range of network scenarios.  相似文献   

12.
Ariadne: A Secure On-Demand Routing Protocol for Ad Hoc Networks   总被引:9,自引:0,他引:9  
An ad hoc network is a group of wireless mobile computers (or nodes), in which individual nodes cooperate by forwarding packets for each other to allow nodes to communicate beyond direct wireless transmission range. Prior research in ad hoc networking has generally studied the routing problem in a non-adversarial setting, assuming a trusted environment. In this paper, we present attacks against routing in ad hoc networks, and we present the design and performance evaluation of a new secure on-demand ad hoc network routing protocol, called Ariadne. Ariadne prevents attackers or compromised nodes from tampering with uncompromised routes consisting of uncompromised nodes, and also prevents many types of Denial-of-Service attacks. In addition, Ariadne is efficient, using only highly efficient symmetric cryptographic primitives.  相似文献   

13.
In ad hoc networks, wireless nodes rely on each other to transmit data over multi-hops by forwarding packets. A selfish node may decide not to forward packets for other nodes to save its own resource but still use the network to send and receive data. Such a selfish behavior can degrade network performance significantly. Most existing work took observation, reputation and token based mechanisms. However observation based mechanism suffers from mobility and collusion; reputation and token based mechanisms suffer from system complexity and efficiency. In this paper, we propose One More Hop (OMH) protocol which suppresses selfish behavior from a totally new angle. Basing on the fact that the selfish but rational nodes still want to receive and send packets, if a node can not determine whether a packet is destined for it or not, it can not drop the packet. With modified routing protocol and cryptographic techniques, OMH achieves this design target. It is robust and efficient. The simulation shows that OMH works well under different network situations.  相似文献   

14.
针对传统路由协议端到端时延长、丢包率过高的现实问题,提出了一种基于贪婪转发的能量感知多路径路由协议(Greedy Forward Energy-aware Multipath Routing Protocol,GFEMRP)。GFEMRP从传感器起始结点出发,如果遇到网络黑洞则选择周边转发方式,否则将选择吞吐量大、且更接近于目的结点的结点作为下一跳结点。利用了OMNET++5.0和INET框架对包括无线自组网按需平面距离向量路由协议(Ad hoc on-demand distance vector routing protocol,AODV),动态按需无线自组织网络(Dynamic MANET On-demand,DYMO),贪婪周边无状态路由无线网络(Greedy Perimeter Stateless Routing for Wireless Networks,GPSR)和GFEMRP协议在内的四种路由协议进行了仿真和比较,实验结果表明GFEMRP协议具有良好的端到端时延、丢包率等性能。  相似文献   

15.
车载自组织网中基于蚁群算法的延迟感知路由协议   总被引:1,自引:0,他引:1  
吴敏  章国安  蔡蓉 《电讯技术》2016,56(10):1086-1092
针对城市道路环境下车载自组织网( VANETs)中通信性能下降以及数据传输失败的问题,提出了一种基于蚁群算法的延迟感知路由( ACDR)协议。首先,建立双向车道的数学延迟模型;然后,根据提出的端点十字路口( EI)的概念,ACDR利用蚁群优化( ACO)寻找最佳路线,其中前向蚂蚁根据本地路段延迟以及当前十字路口与目的节点的端点十字路口之间的全局时延来选择路径,后向蚂蚁则负责在返回路径时更新信息素,同时,相邻十字路口之间利用贪婪转发算法进行数据包的传递。最后仿真比较了ACDR协议与连通性感知路由( CAR)协议的性能,结果表明提出的ACDR协议的数据包的传输延迟小,丢包率低,通信性能好。  相似文献   

16.
In a mobile ad hoc network (MANET), the nodes act both as traffic sources and as relays that forward packets from other nodes along multi-hop routes to the destination. Such networks are suited to situations in which a wireless infrastructure is unavailable, infeasible, or prohibitively expensive. However, the lack of a secure, trusted infrastructure in such networks make secure and reliable packet delivery very challenging. A given node acting as a relay may exhibit Byzantine behavior with respect to packet forwarding, i.e., arbitrary, deviant behavior, which disrupts packet transmission in the network. For example, a Byzantine node may arbitrarily choose to drop or misroute a certain percentage of the packets that are passed to it for forwarding to the next hop. In earlier work, we proposed a trust establishment framework, called Hermes, which enables a given node to determine the “trustworthiness” of other nodes with respect to reliable packet delivery by combining first-hand trust information obtained independently of other nodes and second-hand trust information obtained via recommendations from other nodes. A deficiency of the Hermes scheme is that a node can fail to detect certain types of Byzantine behavior, such as packet misforwarding directed at a particular source node. In this paper, we propose new mechanisms to make Hermes robust to Byzantine behavior and introduce a punishment policy that discourages selfish node behavior. We present simulation results that demonstrate the effectiveness of the proposed scheme in a variety of scenarios involving Byzantine nodes that are malicious both with respect to packet forwarding and trust propagation.  相似文献   

17.
Scalable Routing Protocol for Ad Hoc Networks   总被引:6,自引:0,他引:6  
In this paper we present a scalable routing protocol for ad hoc networks. The protocol is based on a geographic location management strategy that keeps the overhead of routing packets relatively small. Nodes are assigned home regions and all nodes within a home region know the approximate location of the registered nodes. As nodes travel, they send location update messages to their home regions and this information is used to route data packets. In this paper, we derive theoretical performance results for the protocol and prove that the control packet overhead scales linearly with node speed and as N 3/2 with increasing number of nodes. These results indicate that our protocol is well suited to relatively large ad hoc networks where nodes travel at high speed. Finally, we use simulations to validate our analytical model.  相似文献   

18.
(p,q)-Epidemic routing for sparsely populated mobile ad hoc networks   总被引:3,自引:0,他引:3  
This paper considers (p, q )-Epidemic Routing, a class of store-carry-forward routing schemes, for sparsely populated mobile ad hoc networks. Our forwarding scheme includes Two-Hop Forwarding and the conventional Epidemic Routing as special cases. In such forwarding schemes, the original packet is copied many times and its packet copies spread over the network. Therefore those packet copies should be deleted after a packet reaches the destination. We analyze the performance of (p, q)-Epidemic Routing with VACCINE recovery scheme. Unlike most of the existing studies, we discuss the performance of (p, q)-Epidemic Routing in depth, taking account of the recovery process that deletes unnecessary packets from the network.  相似文献   

19.
In traditional stability-oriented route discovery of mobile ad hoc networks, in-between nodes need to rebroadcast identical route request (RREQ) packets, which contain same source node ID and broadcast sequence number, to discover more stable route, yet it increases routing overhead and data transmission delay obviously. Therefore, a stability-oriented route discovery algorithm is proposed to limit routing overhead and decrease transmission delay. In this algorithm, all neighbor nodes of some node will play a mix strategy game named stability-based RREQ forwarding game after receiving an identical RREQ, and independently determine the RREQ forwarding probability based on Nash equilibrium, respectively. The simulation results show that the proposed stability-oriented route discovery algorithm not only reduces routing overhead and transmission delay effectively, but also improve other routing performance.  相似文献   

20.
Chien-Chung  Sundaram   《Ad hoc Networks》2007,5(2):210-227
This paper addresses the issue of improving multicast packet delivery in mobile ad hoc networks and proposes an adaptive mechanism called Protocol-Independent Packet Delivery Improvement Service (PIDIS) to recover lost multicast packets. PIDIS provides its packet-delivery improvement services to any multicast routing protocol for mobile ad hoc networks by exploiting the mechanism of swarm intelligence to make intelligent decisions about where to fetch the lost multicast packets from. PIDIS is a gossip protocol, and nodes using PIDIS are only concerned with which neighbor nodes to gossip with to recover the most lost packets, rather than which member nodes to gossip with. Thus, it does not rely on membership information in a multicast scenario, which is often difficult to get. PIDIS employs the beneficial aspects of probabilistic routing and adapts well to mobility. PIDIS achieves probabilistic improvement in multicast packet delivery and, unlike other gossip-based schemes, does not need to maintain information about group members from which lost multicast packets are retrieved. Further, the operations of PIDIS do not rely on any underlying routing protocol or primitive, and can be incorporated into any ad hoc multicast routing protocol. We incorporated PIDIS over ODMRP [On-Demand Multicast Routing Protocol in Multihop Wireless Mobile Networks, Kluwer Mobile Networks and Applications, 2000], and compared it against Anonymous Gossip (AG) [International Conference on Distributed Computing Systems (ICDCS 2001) Phoenix, Arizona, April 2001] implemented over ODMRP, and ODMRP itself. Our simulation results show that ODMRP + PIDIS is more efficient and performs better than ODMRP + AG and ODMRP in terms of multicast packet delivery, end-to-end delay, and MAC layer overheads. We attribute the better performance and lower MAC overheads of ODMRP + PIDIS to the efficient gossiping made possible by using the swarm intelligence techniques.  相似文献   

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