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1.
SPINS: Security Protocols for Sensor Networks   总被引:77,自引:0,他引:77  
Wireless sensor networks will be widely deployed in the near future. While much research has focused on making these networks feasible and useful, security has received little attention. We present a suite of security protocols optimized for sensor networks: SPINS. SPINS has two secure building blocks: SNEP and TESLA. SNEP includes: data confidentiality, two-party data authentication, and evidence of data freshness. TESLA provides authenticated broadcast for severely resource-constrained environments. We implemented the above protocols, and show that they are practical even on minimal hardware: the performance of the protocol suite easily matches the data rate of our network. Additionally, we demonstrate that the suite can be used for building higher level protocols.  相似文献
2.
自组网路由协议综述   总被引:56,自引:0,他引:56  
史美林  英春 《通信学报》2001,22(11):93-103
自组网路由协议用于监控网络拓扑结构变化,交换路由信息,定位目的节点位置,产生、维护和选择路由,并根据选择的路由转发数据。本文综述了自组网路由协议研究方面的一些最新工作,描述了设计自组网路由协议所面临的问题,并着重对该研究开展以来所提出的各种主要协议进行了对比、分析和分类阐述,为进一步的研究提出了新的课题。  相似文献
3.
Associativity-Based Routing for Ad Hoc Mobile Networks   总被引:52,自引:0,他引:52  
This paper presents a new, simple and bandwidth-efficient distributed routing protocol to support mobile computing in a conference size ad-hoc mobile network environment. Unlike the conventional approaches such as link-state and distance-vector distributed routing algorithms, our protocol does not attempt to consistently maintain routing information in every node. In an ad-hoc mobile network where mobile hosts (MHs) are acting as routers and where routes are made inconsistent by MHs' movement, we employ an associativity-based routing scheme where a route is selected based on nodes having associativity states that imply periods of stability. In this manner, the routes selected are likely to be long-lived and hence there is no need to restart frequently, resulting in higher attainable throughput. Route requests are broadcast on a per need basis. The association property also allows the integration of ad-hoc routing into a BS-oriented Wireless LAN (WLAN) environment, providing the fault tolerance in times of base stations (BSs) failures. To discover shorter routes and to shorten the route recovery time when the association property is violated, the localised-query and quick-abort mechanisms are respectively incorporated into the protocol. To further increase cell capacity and lower transmission power requirements, a dynamic cell size adjustment scheme is introduced. The protocol is free from loops, deadlock and packet duplicates and has scalable memory requirements. Simulation results obtained reveal that shorter and better routes can be discovered during route re-constructions.  相似文献
4.
This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.  相似文献
5.
毫米波副载波光纤通信技术的研究进展   总被引:31,自引:10,他引:21  
方祖捷  叶青  刘峰  瞿荣辉 《中国激光》2006,33(4):81-488
综述了用于下一代移动通信的光纤毫米波副载波通信技术(ROF)的研究进展。介绍了系统的基本构想和涉及的关键技术。着重介绍几种毫米波副载波光发射器以及有关光学技术的新进展,包括外调制器方法、射频上转换法、光学外差法、毫米波调制光脉冲发生器等;简要介绍了ROF接收技术、系统技术和有关应用的研究动向。  相似文献
6.
Analysis of TCP Performance over Mobile Ad Hoc Networks   总被引:27,自引:0,他引:27  
Mobile ad hoc networks have attracted attention lately as a means of providing continuous network connectivity to mobile computing devices regardless of physical location. Recent research has focused primarily on the routing protocols needed in such an environment. In this paper, we investigate the effects that link breakage due to mobility has on TCP performance. Through simulation, we show that TCP throughput drops significantly when nodes move, due to TCP's inability to recognize the difference between link failure and congestion. We also analyze specific examples, such as a situation where throughput is zero for a particular connection. We introduce a new metric, expected throughput, for the comparison of throughput in multi-hop networks, and then use this metric to show how the use of explicit link failure notification (ELFN) techniques can significantly improve TCP performance.  相似文献
7.
On-Demand Multicast Routing Protocol in Multihop Wireless Mobile Networks   总被引:27,自引:0,他引:27  
An ad hoc network is a dynamically reconfigurable wireless network with no fixed infrastructure or central administration. Each host is mobile and must act as a router. Routing and multicasting protocols in ad hoc networks are faced with the challenge of delivering data to destinations through multihop routes in the presence of node movements and topology changes. This paper presents the On-Demand Multicast Routing Protocol (ODMRP) for wireless mobile ad hoc networks. ODMRP is a mesh-based, rather than a conventional tree-based, multicast scheme and uses a forwarding group concept; only a subset of nodes forwards the multicast packets via scoped flooding. It applies on-demand procedures to dynamically build routes and maintain multicast group membership. ODMRP is well suited for ad hoc wireless networks with mobile hosts where bandwidth is limited, topology changes frequently, and power is constrained. We evaluate ODMRP performance with other multicast protocols proposed for ad hoc networks via extensive and detailed simulation.  相似文献
8.
移动ad hoc网络安全综述   总被引:26,自引:1,他引:25  
移动ad hoc网络是由移动节点自组织形成的网络,由于其动态拓扑、无线通信的特点,容易遭受各种安全威胁.该文介绍了移动ad hoc网络安全研究的最新研究进展.首先从传输信道、移动节点、动态拓扑、安全机制、路由协议几方面,分析了移动ad hoc网络的安全弱点,然后将移动ad hoc网络安全方面的研究分为三个方向:密钥分配与管理、入侵检测、增强合作.对每个方向内一些典型安全方案也进行了分类论述,同时分析了各种方案的优点和缺点,并进行了综合比较.文中阐明了目前协议存在的一些问题并提出了相应的改进方法,最后指出了下一步研究方向.  相似文献
9.
基于移动代理技术网管模型性能的研究   总被引:25,自引:2,他引:23  
随着网络运行结构的复杂和规模的不断扩大,基于客户/服务方式的网管模型已经不能适应网络管理的需要,基于移动代理的网络管理已经成为分布式网络管理的研究热点,本文主要分析了基于移动代理的网络管理结构模型,提出了一个实际的网络管理架构,并将它与传统的网络管理模型进行了比较分析,最后,进行了一些实验测试其性能指标。1  相似文献
10.
A Survey of Energy Efficient Network Protocols for Wireless Networks   总被引:25,自引:0,他引:25  
Wireless networking has witnessed an explosion of interest from consumers in recent years for its applications in mobile and personal communications. As wireless networks become an integral component of the modern communication infrastructure, energy efficiency will be an important design consideration due to the limited battery life of mobile terminals. Power conservation techniques are commonly used in the hardware design of such systems. Since the network interface is a significant consumer of power, considerable research has been devoted to low-power design of the entire network protocol stack of wireless networks in an effort to enhance energy efficiency. This paper presents a comprehensive summary of recent work addressing energy efficient and low-power design within all layers of the wireless network protocol stack.  相似文献
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