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1.
Secure routing in mobile wireless ad hoc networks   总被引:3,自引:0,他引:3  
We discuss several well known contemporary protocols aimed at securing routing in mobile wireless ad hoc networks. We analyze each of these protocols against requirements of ad hoc routing and in some cases identify fallibilities and make recommendations to overcome these problems so as to improve the overall efficacy of these protocols in securing ad hoc routing, without adding any significant computational or communication overhead.  相似文献   

2.
Mobile ad hoc networks are infrastructure-free, pervasive and ubiquitous in nature, without any centralized authority. These unique characteristics coupled with the growing concerns for security attacks demand an immediate solution for securing the ad hoc network, prior to its full-fledged deployment in commercial and military applications. So far, most of the research in mobile ad hoc networks has been primarily focused on routing and mobility aspects rather than securing the ad hoc networks themselves. Due to ever increasing security threats, there is a need to develop schemes, algorithms, and protocols for a secured ad hoc network infrastructure. To realize this objective, we have proposed a practical and effective security model for mobile ad hoc networks. The proposed predictive security model is designed using a fuzzy feedback control approach. The model is based on identifying critical network parameters that are affected by various types of attacks and it continuously monitors those parameters. Once we measure the relative change in these parameter values, we could detect the type of attack accurately and protect the system, without compromising its effectiveness. Experimental results of the model simulated for selected packet mistreatment attacks and routing attacks are very promising.  相似文献   

3.
With sensor networks on the verge of deployment, security issues pertaining to the sensor networks are in the limelight. Though the security in sensor networks share many characteristics with wireless ad hoc networks, the two fields are rapidly diverging due to the fundamental differences between the make‐up and goals of the two types of networks. Perhaps the greatest dividing difference is the energy and computational abilities. Sensor nodes are typically smaller, less powerful, and more prone to failure than nodes in an ad hoc network. These differences indicate that protocols that are valid in the context of ad‐hoc networks may not be directly applicable for sensor networks. In this paper, we survey the state of art in securing wireless sensor networks. We review several protocols that provide security in sensor networks, with an emphasis on authentication, key management and distribution, secure routing, and methods for intrusion detection. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

4.
Predicting the performance of ad hoc networking protocols for mesh networks has typically been performed by making use of software based simulation tools. Experimental study and validation of such predictions is a vital to obtaining more realistic results, but may not be possible under the constrained environment of network simulators. This paper presents an experimental comparison of OLSR using the standard hysteresis routing metric and the ETX metric in a 7 by 7 grid of closely spaced Wi-Fi nodes to obtain more realistic results. The wireless grid is first modelled to extract its ability to emulate a real world multi-hop ad hoc network. This is followed by a detailed analysis of OLSR in terms of hop count, routing traffic overhead, throughput, delay, packet loss and route flapping in the wireless grid using the hysteresis and ETX routing metric. It was discovered that the ETX metric which has been extensively used in mesh networks around the world is fundamentally flawed when estimating optimal routes in real mesh networks and that the less sophisticated hysteresis metric shows better performance in large dense mesh networks.  相似文献   

5.
为找到一种适合短波Ad hoc网络使用的路由协议,通过OPNET仿真软件对短波信道进行建模,在该模型的基础上对无线Ad Hoc常用的3种路由协议:优化链路状态路由(Optimized Link State Routing,OLSR)、反应式路由中的动态源路由(Dynamic Source Routing,DSR)和按需距离矢量(Ad hoc On Demand Distance Vector,AODV)进行仿真分析。仿真结果表明,OLSR路由协议网络时延最小、吞吐量最高和数据丢失率最低,其整体性能优于AODV及DSR路由协议,更适合于短波信道,但是OLSR路由协议也存在着开销高的不足,下一步可以针对降低路由开销进行研究。  相似文献   

6.
Within ad hoc and wireless sensor networks, communications are accomplished in dynamic environments with a random movement of mobile devices. Thus, routing protocols over these networks are an important concern to offer efficient network scalability, manage topology information, and prolong the network lifetime. Optimized link state routing (OLSR) is one of those routing protocols implemented in ad hoc and wireless sensor networks. Because of its proactive technique, routes between two nodes are established in a very short time, but it can spend a lot of resources for selecting the multipoint relays (MPRs: nodes responsible for routing data) and exchanging topology control information. Thus, nodes playing for a long time a role of MPR within networks implementing such protocol can rapidly exhaust their batteries, which create route failures and affect the network lifetime. Our main approach relies on analyzing this concern by introducing a new criterion that implements a combination between the residual energy of a node and its reachability in order to determine the optimal number of MPRs and sustain the network lifetime. Simulations performed illustrate obviously that our approach is more significant compared with the basic heuristic used by original OLSR to compute the MPR set of a node.  相似文献   

7.
Ad Hoc网络的安全问题和安全策略   总被引:8,自引:2,他引:6  
周海刚  肖军模 《电信科学》2001,17(12):39-42
AdHoc网络作为一种无线移动网络正成为网络研究,特别是军事研究的一个热点。由于AdHoc网络的特点,其安全问题和安全策略正受到越来越广播的重视。文中介绍了AdHoc网络的特点,论述了AdHoc网络和路由协议的安全问题,最后讨论并提出了AdHoc网络的一些安全策略。  相似文献   

8.
Ad hoc networks can be used for quickly set up small spontaneous networks, such as in emergency situations or during sessions of cooperative works as in conferences, teaching rooms or meetings. Real-life tests of such networks are invaluable in order to assess models used in simulation. However, the number of factors affecting the performance of an ad hoc network is high, theoretically infinite. There are, for example, system factors, such as routing protocols, MAC and physical layer protocols and their cross-layer interaction, as well as environment factors, such as the presence of walls, foliage and surrounding moving objects. In order to optimize protocols, it is important both to design repeatable experiments of the network and to identify the parameters which really affect the system behavior. We accomplish the former demand by building a simple network by means of off-the-shelf hardware and software. For the latter point, we propose to use methods of statistical testing theory to identify these parameters in a compact manner. In particular, we use OLSR as a routing protocol. Results from real experiments in outdoor and indoor scenarios confirm the horizon effect of ad hoc multi-hop networks and show that there is a treatment effect caused by the window size of OLSR.  相似文献   

9.
Routing in mobile ad hoc networks is a complex task due to the mobility of the nodes and the constraints linked to a wireless multihop network (e.g., limited bandwidth, collisions, and bit errors). These adverse conditions impair not only data traffic but also routing signaling traffic, which feeds route computation. In this contribution, we propose to use satellite communications to help in the distribution of mobile ad hoc network routing signaling. The optimized link‐state routing (OLSR) is chosen among several routing protocols to be extended with satellite‐based signaling, yielding a version we call OLSR hybrid signaling (OLSR‐H). This new scheme is evaluated through simulations and yields improvements of approximately 10% in the data delivery ratio compared with a regular OLSR. This evaluation is conducted using two different network topology models, one being fit for representing forest firefighting operations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

10.
Provably Secure On-Demand Source Routing in Mobile Ad Hoc Networks   总被引:5,自引:0,他引:5  
Routing is one of the most basic networking functions in mobile ad hoc networks. Hence, an adversary can easily paralyze the operation of the network by attacking the routing protocol. This has been realized by many researchers and several "secure" routing protocols have been proposed for ad hoc networks. However, the security of those protocols has mainly been analyzed by informal means only. In this paper, we argue that flaws in ad hoc routing protocols can be very subtle, and we advocate a more systematic way of analysis. We propose a mathematical framework in which security can be precisely defined and routing protocols for mobile ad hoc networks can be proved to be secure in a rigorous manner. Our framework is tailored for on-demand source routing protocols, but the general principles are applicable to other types of protocols too. Our approach is based on the simulation paradigm, which has already been used extensively for the analysis of key establishment protocols, but, to the best of our knowledge, it has not been applied in the context of ad hoc routing so far. We also propose a new on-demand source routing protocol, called endairA, and we demonstrate the use of our framework by proving that it is secure in our model  相似文献   

11.
The proliferation of mobile wireless computing devices and the increasing usage of wireless networking have motivated substantial research in mobile ad hoc networks (MANETs). In addition, much has also been done to link autonomous MANETs to the Internet, and as MANETs become more prevalent, the need to interconnect multiple MANETs becomes increasingly important too. However, direct interconnection of MANETs has rarely been studied. In this paper, we first report an experimental study on the performance of interconnected MANETs running two different routing protocols, viz., the Ad hoc On-Demand Distance Vector (AODV) and Optimized Link State Routing (OLSR) protocols, which represent the two major categories, and show that with the use of multiple gateways, it is possible to viably interconnect multiple networks running different MANET routing protocols. We then follow with a simulation study to evaluate the performance in large networks, which not only validates the scalability of the proposed scheme, but also helps to identify various problems that were not apparent in small experimental networks.  相似文献   

12.
The dynamic nature of mobile nodes of ad hoc network is mostly affected by security problems which reduce data forwarding rate in multimedia sources. Due to the rapid growth of wireless applications, the different multitalented routing protocols are proposed in recent years. But the recent protocols are not efficient for multimedia applications, till now, specific security aware routing protocols are not proposed for multimedia data transfers. In this paper, we proposed trust enhanced cluster based multipath routing (TECM) algorithm. We use energy efficient PSO algorithm used to create cluster formation and cluster head, super cluster head are selected from trust values, which compute form proposed TECM algorithm. The multi trust factors are used for trust computation, such as frame/packet loss ratio, frame/packet forward energy, frame/packet receiving energy, routing overhead, received signal strength, frame/packet forward rate, average forward delay and protocol deviation flag. We then combine proposed TECM algorithm with standard multipath OLSR protocol (TECM-OLSR) to analyze the performance of proposed algorithm. The simulated results show that proposed TECM-OLSR protocol is very effective in terms of loss and delivery rate, delay, routing overhead and network lifetime compare to FPNT-OLSR.  相似文献   

13.
A performance evaluation of real time services (such as video streaming) over mobile ad-hoc networks using both hierarchical and flat routing protocols is shown in this paper. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network have been simulated using NS-2. We use OLSR (Optimized Link State Protocol) as the flat routing protocol and our own implementation of HOLSR (Hierarchical OLSR)—which uses HNA (Host and Network Association) messages—as the hierarchical one, modifying other previous HOLSR version and maintaining the maximum compatibility with the flat OLSR. We carry out a complete comparison between these protocols focused on video evaluation. The simulation lets us compare the quality of service (QoS) of the video streaming paying attention to objective parameters (PSNR, packet delivery ratio, packet delay and interruptions). Some drawbacks of the hierarchical environment are also analyzed, as the link load between cluster heads and the lack of QoS-state-aware in HOLSR design. Quantitative results indicate that the protocol overhead is reduced (more than 40% in larger networks) and the video quality is improved (from 1 to 6 dB in certain cases) using hierarchical protocols.  相似文献   

14.
This article reviews the hierarchical optimized link state routing (HOLSR) mechanism for heterogeneous mobile ad hoc networks. In this work a heterogeneous mobile ad hoc network is defined as a network of mobile nodes that are characterized by different communications capabilities, such as multiple radio interfaces. The article focuses on proposing the HOLSR protocol. The HOLSR mechanism is derived from the OLSR protocol; however, unlike OLSR, the HOLSR protocol takes advantage of different mobile node capabilities to reduce the routing control overhead in large heterogeneous ad hoc networks, thus improving the performance of the routing mechanism.  相似文献   

15.
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   

16.
The effective tremendous deployment of ad hoc networks is incontestably braked by their unreliability in terms of security and quality of services. In this paper, we focus on security problems and show that despite of efforts made in the ad hoc security field, many security issues still jeopardize correct MANETs routing operation. For such threats, we propose an IDS (Intrusion Detection System) solution for which cryptographic-based solutions are ineffective. Actually, authenticated nodes legitimately present in the network are able to send faked routing messages to compromise the routing and then communication between nodes. To cope with such security attacks, we propose an IDS dedicated to the OLSR protocol and well fitted to its characteristics and operation. In addition, our IDS is implemented on all network’s nodes which act cooperatively by continually analyzing routing messages semantics. When an intrusion is detected, alerts are flooded and intruders are banished from the network. We have finally implemented this IDS and performances evaluation shows the intrusion detection effectiveness.  相似文献   

17.
A mobile ad hoc network does not require fixed infrastructure to construct connections among nodes. Due to the particular characteristics of mobile ad hoc networks, most existing secure protocols in wired networks do not meet the security requirements for mobile ad hoc networks. Most secure protocols in mobile ad hoc networks, such as secure routing, key agreement and secure group communication protocols, assume that all nodes must have pre‐shared a secret, or pre‐obtained public‐key certificates before joining the network. However, this assumption has a practical weakness for some emergency applications, because some nodes without pre‐obtained certificates will be unable to join the network. In this paper, a heterogeneous‐network aided public‐key management scheme for mobile ad hoc networks is proposed to remedy this weakness. Several heterogeneous networks (such as satellite, unmanned aerial vehicle, or cellular networks) provide wider service areas and ubiquitous connectivity. We adopt these wide‐covered heterogeneous networks to design a secure certificate distribution scheme that allows a mobile node without a pre‐obtained certificate to instantly get a certificate using the communication channel constructed by these wide‐covered heterogeneous networks. Therefore, this scheme enhances the security infrastructure of public key management for mobile ad hoc networks. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

18.
A survey of routing attacks in mobile ad hoc networks   总被引:3,自引:0,他引:3  
Recently, mobile ad hoc networks became a hot research topic among researchers due to their flexibility and independence of network infrastructures, such as base stations. Due to unique characteristics, such as dynamic network topology, limited bandwidth, and limited battery power, routing in a MANET is a particularly challenging task compared to a conventional network. Early work in MANET research has mainly focused on developing an efficient routing mechanism in such a highly dynamic and resource-constrained network. At present, several efficient routing protocols have been proposed for MANET. Most of these protocols assume a trusted and cooperative environment. However, in the presence of malicious nodes, the networks are vulnerable to various kinds of attacks. In MANET, routing attacks are particularly serious. In this article, we investigate the state-of-the-art of security issues in MANET. In particular, we examine routing attacks, such as link spoofing and colluding misrelay attacks, as well as countermeasures against such attacks in existing MANET protocols.  相似文献   

19.
Ad hoc网络的特征是多跳的无线连接,网络拓扑的频繁变化,以及需要有效的动态路由协议。重点比较Ad hoc网络中两种主要的按需路由协议:动态源路由(DSR)协议和Ad hoc按需距离矢量路由(AODV)协议。尽管DSR和AODV都是按需路由协议,但不同的协议机制导致了网络性能的显著差异。在OPNET仿真平台下,对采用不用路由协议的网络时延和吞吐量进行比较,从而分析不同的路由机制引起的网络性能差异。  相似文献   

20.
In this work we propose the use of more detailed graphics to study the performance of routing protocols for mobile multihop ad hoc networks when studying the feasibility of providing quality of service to upper layer real--time applications. Classic success ratio and round trip time curves provide important parameters to study and compare routing protocols, but they also mask valuable information about the evolution of the network. This masquerading is due to the averaging techniques used in classic curves. The dynamic behavior of the network makes these curves inappropriate when analyzing routing protocols with quality of service constraints. In order to obtain more detailed graphics, we propose the use of time windows and discrimination of the results on a per link basis. Our proposal provides better comprehension of the routing protocol characteristics and its applicability to quality of service in mobile multihop ad hoc networks.  相似文献   

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