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1.
Bin Xie Anup Kumar Dharma P. Agrawal 《Wireless Communications and Mobile Computing》2008,8(9):1129-1148
Integration of ad hoc networks with the Internet provides global Internet connectivity for ad hoc hosts through the coordination of mobile IP and ad hoc protocols. In a pure ad hoc network, it is difficult to establish trust relationship between two ad hoc hosts due to lack of infrastructure or centralized administration. In this paper, an infrastructure‐supported and distributed authentication protocol is proposed to enhance trust relationships amongst ad hoc hosts. In addition, an effective secure routing protocol (SRP) is discussed to protect the multi‐hop route for Internet and ad hoc communication. In the integrated ad hoc networks with Internet accessibility, the ad hoc routing security deployed with the help of infrastructure has a fundamental impact on ad hoc hosts in term of Internet access, integrity, and authentication. Both analysis and simulation results demonstrate the effectiveness of the proposed security protocol. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
2.
Chengalur-Smith I. Belardo S. Pazer H. 《Engineering Management, IEEE Transactions on》1999,46(2):210-220
Ad hoc forecasts are generally unstructured forecasts that are performed infrequently. Unfortunately, there are no widely accepted formulae for performing such tasks. In this paper, the authors draw parallels between the process of ad hoc forecasting and disaster management, using characteristics of disasters to develop analogous dimensions for ad hoc forecasts, Although a given unit within an organization may not have the opportunity to repeat a particular ad hoc forecast, there are certain similarities among ad hoc forecasts performed by different units within an organization. Mapping ad hoc forecasts along the disaster characteristics brings out these similarities and allows one to identify technology-based strategies for improving ad hoc forecasts. Just as disaster planning draws together people from different units of the organization and creates a common knowledge base, they propose the creation of a common repository of ad hoc forecasts that member organizations can draw upon. This allows organizations that find themselves in need of a particular ad hoc forecast to learn from both the disaster management literature and their own experiences. The presence of the Internet and the World Wide Web provide the infrastructure for creating an inter-organizational information system 相似文献
3.
Probabilistic analysis of routes on mobile ad hoc networks 总被引:1,自引:0,他引:1
Wei-Ho Chung 《Communications Letters, IEEE》2004,8(8):506-508
The ad hoc network is comprised of mobile nodes without wires or any infrastructures. All data are transmitted from source node to destination node through wireless channels. The ad hoc network is self-organized by ad hoc network routing protocols. Due to the mobility of nodes, the route which is constructed from many proposed ad hoc network routing protocols and comprised of several direct node-to-node links exists only for a certain period. That also means the route is subject to frequent breakages. In this letter, the probabilistic behavior of a constructed route is investigated through simulation and curve fitting. The simulation results show that the probability density function of a route is exponential distribution. The simulation also shows how the time proportion is distributed among different route lengths under a certain scenario. The route is a basic factor in the ad hoc network which operates without any central controller. The characteristics of the route have much influence on the performance of the ad hoc network. Thus the probabilistic analysis provides important implications when we are designing ad hoc network routing protocols and deploying ad hoc networks. 相似文献
4.
Efficient flooding with passive clustering-an overhead-free selective forward mechanism for ad hoc/sensor networks 总被引:8,自引:0,他引:8
Taek Jin Kwon Gerla M. Varma V.K. Barton M. Hsing T.R. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2003,91(8):1210-1220
High capacity real-time data communications in sensor networks usually require multihop routing and ad hoc routing protocols. Unfortunately, ad hoc routing protocols usually do not scale well and cannot handle dense situations efficiently. These two issues-scalability and density-are the major limitations when we apply ad hoc routing schemes to sensor networks. Passive clustering (PC) classifies ad hoc/sensor nodes into critical and noncritical nodes without any extra transmission. By 2-b piggybacking and monitoring user traffic (e.g., data polling requests from a sink), PC deploys the clustering structure "for free". Moreover, PC makes even the first flooding as efficient as all subsequent floodings (i.e., no initialization overhead). PC introduces many benefits, including efficient flooding and density adaptation. As a result, PC reduces control overhead of ad hoc routing protocols significantly and, as a consequence, enables ad hoc routing in large, dense sensor networks. The resulting structure can be utilized in cluster-based ad hoc network/sensor networking as well as for active node selection. 相似文献
5.
MinSheng 《电子科学学刊(英文版)》2003,20(5):344-352
In this paper, the capacity of multi-channel, multi-hop ad hoc network is evaluated.In particular, the performance of multi-hop ad hoc network with single channel IEEE 802.11 MAC utilizing different topologies is shown. Also the scaling laws of throughputs for largescale ad hoc networks and the theoretical guaranteed throughput bounds for multi-channel grid topology systems are proposed. The results presented in this work will help researchers to choose the proper parameter settings in evaluation of protocols for multi-hop ad hoc networks. 相似文献
6.
《Communications Magazine, IEEE》2008,46(6):146-146
The three articles in this special series focus on ad hoc and sensor networks topics. The articles cover three different pragmatic directions that successfully exploited the ad hoc paradigm: wireless sensor networks (WSNs), wireless mesh networks, and vehicular ad hoc networks (VANETs). 相似文献
7.
移动Ad Hoc网络安全按需路由协议 总被引:1,自引:0,他引:1
Ad Hoc网络的安全性问题越来越引起人们的关注,如何确保Ad Hoc网络路由协议的安全成为Ad Hoc研究的一项关键技术。提出一种适用于移动Ad Hoc网络的安全按需源路由协议,利用移动节点之间的会话密钥和基于散列函数的消息鉴别码HMAC一起来验证路由发现和路由应答的有效性。提出的邻居节点维护机制通过把MAC地址和每个节点的ID绑定来防御各种复杂的攻击如虫洞攻击。NS-2仿真表明该协议能有效地探测和阻止针对Ad Hoc网络的大部分攻击。 相似文献
8.
Extending Global IP Connectivity for Ad Hoc Networks 总被引:1,自引:0,他引:1
Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed. 相似文献
9.
Ad hoc是一种具有有限生存期的无基础设施网络.尽管它的设计初衷是用于军事,但Ad hoc因其独特的性能,却成为了未来通信技术的重要组成.Ad hoc与后3G移动通信的结合成为Ad hoc发展的趋势,但也为Ad hoc提出了新的挑战. 相似文献
10.
ATP: a reliable transport protocol for ad hoc networks 总被引:3,自引:0,他引:3
Sundaresan K. Anantharaman V. Hung-Yun Hsieh Sivakumar A.R. 《Mobile Computing, IEEE Transactions on》2005,4(6):588-603
Existing works have approached the problem of reliable transport in ad hoc networks by proposing mechanisms to improve TCP's performance over such networks, In this paper, we show through detailed arguments and simulations that several of the design elements in TCP are fundamentally inappropriate for the unique characteristics of ad hoc networks. Given that ad hoc networks are typically stand-alone, we approach the problem of reliable transport from the perspective that it is justifiable to develop an entirely new transport protocol that is not a variant of TCP. Toward this end, we present a new reliable transport layer protocol for ad hoc networks called ATP (ad hoc transport protocol). We show through ns2-based simulations that ATP outperforms default TCP as well as TCP-ELFN and ATCP. 相似文献
11.
无人机自组网技术研究 总被引:1,自引:0,他引:1
在无人机系统中,编组和协同作战能力对提高无人机作站效能和生存能力具有重要意义。无线自组网是一种特殊结构的无线通信网络,其通信依靠节点之间的相互协作,以无线多跳方式完成,因此网络不依赖于任何固定设施,具有自组织和自管理的特性,这种特殊的组网方式使得无线自组网非常适用于无人机系统。介绍了无线自组网的原理,分析了无线自组网应用于无人机系统主要面临的关键技术:路由技术和安全问题。介绍了无线自组网的发展情况和在无人机领域的研究情况。 相似文献
12.
Link states are studied in ad hoc network. The characters of unidirectional links are discussed. Unidirectional link-state advertisement based on power control mechanism (ULAPC) for mobile ad hoc networks (MANET) is designed. ULAPC is able to advertise unidirectional link-state to relational nodes. And it may offer help for process of routing discovery in ad hoc network. Based on ULAPC, the routing method solving the problem of unidirectional link is described in ad hoc network. Simulation results show the performance of ULAPC is better than the traditional routing protocols in many aspects. 相似文献
13.
14.
目前,VoIP技术及其业务迅速发展,在无线自组织网络中有广泛的应用,有必要对于VoIP在无线自组网中的传输进行分析研究。利用NS-2作为仿真工具对G.711编码标准下多跳无线自组织网中VoIP的传输进行仿真,使用802.11MAC层协议和AODV路由层协议。实验结果表明,无线自组织网络环境下VoIP系统性能(包括丢包率、时延等)受到多跳影响。 相似文献
15.
The strongest feature of ad hoc networks is its capability to be rapidly deployed anywhere and anytime without relying on
a pre-existing infrastructure. From there, ad hoc networks offer the advantages to be auto-organized, ubiquitous, dynamic
and completely autonomous. As a counter part, securing them becomes a more difficult task, especially because of the absence
of centralized entities in the network. Inevitably, the security problem presents currently a hot topic raising more and more
challenges within industrials and researchers, and many interesting securing solutions were meanwhile proposed, omitting however
to suit to ad hoc networks characteristics and therefore disadvantaging them. In this paper, we propose a securing scheme
for the OLSR routing protocol based on the secret sharing idea. We initially expose the general characteristics and the security
problems related to ad hoc routing protocols. We then address the security requirements of ad hoc routing protocols and the
security requirements we focus on. Finally, we define our completely and distributed securing algorithm based on threshold
cryptography. A primary main conception objective being to suit as much as possible to ad hoc networks characteristics by
avoiding as much as possible assumptions contradictory with the auto-organized and dynamic nature of ad hoc networks. Simulation
results depict the additional delay due to security enhancements. Results show that this delay stills suitable to OLSR routing
specifications. 相似文献
16.
In ad hoc networks there is a need for all-to-one protocols that allow for information collection or “sensing” of the state of an ad hoc network and the nodes that comprise it. Such protocols may be used for service discovery, auto-configuration, network management, topology discovery or reliable flooding. There is a parallel between this type of sensing in ad hoc networks and that of sensor networks. However, ad hoc networks and sensor networks differ in their application, construction, characteristics and constraints. The main priority of sensor networks is for the flow of data from sensors back to a sink, but in an ad hoc network this may be of secondary importance. Hence, protocols suitable to sensor networks are not necessarily suitable to ad hoc networks and vice versa. We propose, Resource Aware Information Collection (RAIC), a distributed two phased resource aware approach to information collection in ad hoc networks. RAIC utilises a resource aware optimised flooding mechanism to both disseminate requests and initialise a backbone of resource suitable nodes responsible for relaying replies back to the node collecting information. RAIC in the process of collecting information from all nodes in an ad hoc network is shown to consume less energy and introduce less overhead compared with Directed Diffusion and a brute force approach. Importantly, over multiple successive queries (in an energy constrained environment), the use of resource awareness allows for the load of relaying to be distributed to those nodes most suitable, thereby extending the lifetime of the network. 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.
本文介绍了ad hoc网络可生存性面临的问题和挑战,特别强调了军事需求.其中从三个方面探讨了ad hoc网络的可生存性问题:可生存的网络连接、可生存的通信服务及可生存性技术,尤其是对可生存性技术进行了较全面的剖析. 相似文献
19.
The IEEE 802.11 MAC protocol is the standard for wireless LANs; it is widely used in testbeds and simulations for wireless multihop ad hoc networks. However, this protocol was not designed for multihop networks. Although it can support some ad hoc network architecture, it is not intended to support the wireless mobile ad hoc network, in which multihop connectivity is one of the most prominent features. In this article we focus on the following question: can the IEEE 802.11 MAC protocol function well in multihop networks? By presenting several serious problems encountered in an IEEE 802.11-based multihop network and revealing the in-depth cause of these problems, we conclude that the current version of this wireless LAN protocol does not function well in multihop ad hoc networks. We thus doubt whether the WaveLAN-based system is workable as a mobile ad hoc testbed 相似文献
20.
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