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1.
    
The discovery and management of desired network services present significant challenges for mobile networks. Based on the Service Location Protocol, this paper proposes an integrated service discovery architecture for vehicular ad hoc networks. The proposed approach divides the network into several logical zones. The zone structure is formed virtually based on position information. Each logical zone may have a zone directory agent to manage registered services from service providers. The proposed architecture considers both vehicle‐to‐infrastructure and vehicle‐to‐vehicle communication modes and introduces roadside directory agents and vehicle directory agents to reduce deployment costs. We also introduce a substitute query technique, cache mechanism, and backup mechanism to improve the request hit ratio and reduce the message overhead of the substitute query. Finally, we implement the proposed mechanisms in Network Simulator version 2, with simulation results showing that the proposed architecture can provide a high average data hit ratio and low message overhead. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

2.
    
Traffic congestion, air pollution, fuel wastage, and car accidents are all exacerbated by increased traffic. Thus, vehicular communications, which refer to information transmission between cars, pedestrians, and infrastructures, have lately gained popularity and been extensively explored due to their enormous potential to enable intelligent transportation and various safety applications. Manually piloted cars and automated vehicles can acquire relevant information via vehicular communications to enhance traffic security and boost entertainment services. The basic concept of automobile clouds was originally published in the literature not long ago, and several suggested structural approaches have been presented in this study thus far. Several academics have concentrated on the structural layout to address various problems and, as a result, satisfy user expectations in order to give dependable services. We examined various vehicular cloud topologies in this study. We also offered a complete summary of current network layer research on allowing efficient vehicle communications and examined specific security, architectural, and reliability concerns in vehicular clouds. Also, the taxonomy of vehicular networks was discussed in terms of the service link between vehicular networks and cloud computing. Ultimately, we discussed the research prospects available. The results showed that security and privacy challenges are among the most important challenges.  相似文献   

3.
    
Cloud computing is alluring for the vehicular mesh (VMesh) network. Cloud computing stipulates the computing resources and services on demand using the Internet. The VMesh network is a type of networking where each vehicle must not only capture and disseminate its own data but also serve as a gateway for another vehicle. The cloud‐VMesh network is a convergent technology encompassed of three key technologies, namely, vehicular mesh network, cloud computing, and networking. In this paper, we propose a new routing algorithm for cloud‐VMesh network, dubbed as adroit algorithm. The proposed adroit algorithm addresses the choosing of an optimal gateway and base station in the network layer from and to the service requesters and cloud server. The simulation study shows that the adroit algorithm augments the routing issues such as delay, packet loss, congestion and deployment cost in the cloud‐VMesh network, and it is justified based on the packet delivery ratio, average response time, routing overhead ratio, and packet collision ratio. The simulation results demonstrate that the adroit algorithm outperforms the existing protocols. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

4.
智能光网络与传统光网的根本区别就在于明确的提出了控制平面的概念。其中网络拓扑(节点和连接)及其可用资源是网络操作的基础。理想状态下,网络拓扑和资源应该是自动发现的,这就要求邻居发现以及在整个网络进行信息发布的机制。此外,智能光网络的边缘节点应该具有业务发现能力,从而在以UNI接口模型实现的网络互联中,UNI-C指示客户设备能力且从UNI-N获取跟传送网络业务能力有关的信息。  相似文献   

5.
张文芳  雷丽婷  王小敏  王宇 《电子学报》2000,48(9):1814-1823
针对目前车联网认证密钥协商协议效率低下以及车辆公私钥频繁更新的问题,提出一个基于无证书聚合签名的车联网匿名认证与密钥协商协议.本方案通过引入临时身份和预签名机制实现对车辆的隐私保护以及匿名认证,同时通过构建临时身份索引数据库,实现可信中心对可疑车辆的事后追查,满足车辆的条件匿名性要求.此外,本方案中车辆的公私钥不随其临时身份动态改变,有效避免了已有方案公私钥频繁更新带来的系统开销.同时,为了提供高效的批量认证,采用无双线性对的聚合签名技术,实现了车辆签名的动态聚合和转发,有效降低了签名传递的通信量和云服务器的验证开销.本文方案在eCK模型和CDH问题假设下被证明是形式化安全的.  相似文献   

6.
为满足用户的性能需求及服务质量保障,针对复杂网络服务组合的特点和用户个性化的服务质量(Quality of Service, QoS)需求,研究了云环境下的网络感知服务组合问题,利用云服务和网络服务的QoS属性,提出了一种基于最优路径选择(Optimal Path Selection, OPS)的网络感知服务组合算法。该算法可以提升网络服务质量水平,改善用户体验质量。仿真结果表明,该算法在求解时间和质量两个方面都表现出了良好的性能,而且能动态适应用户复杂的需求,能够有效地解决云计算环境下的服务组合问题。  相似文献   

7.
为解决车辆移动及边缘服务器有限服务范围造成的服务中断问题,为车辆边缘网络提出一种基于多参数马尔可夫决策过程的动态服务迁移算法.通过构造包含时延、带宽、服务器处理能力及车辆运动信息的多参数MDP收益函数,弥补了单纯基于距离进行服务迁移方案的不足;不再使用单一迁移目标服务器,结合车辆运动及时延限制构造候选服务器集合,基于B...  相似文献   

8.
    
Road accidents and traffic congestion are the unavoidable consequences of the growing number of vehicles on the road. Conventional management systems are not effective in mitigating these issues. However, a range of technologies, including sensors, processors, vehicle-based resources, and mobile cloud computing, can help solve traffic and safety problems. Vehicular cloud networks, a cutting-edge technology for the development of intelligent transportation systems, face significant challenges, such as ensuring reliable service providers that maintain stable connections between vehicles. Roadside units (RSUs) play a crucial role in these networks, but they come with several drawbacks, including high costs, imbalanced load distribution, and unreliable connections. To address these issues, we propose the Traffic Control and Safety in Vehicular Networks (TCaS-VN) algorithm, a cloud-based sharing services framework for vehicles that eliminates the need for RSUs. This approach offers several advantages, including a twofold improvement in the lifetime of clusters, the elimination of noncluster head nodes, a 54% reduction in overhead, a 58% reduction in service search time, and a success rate of over 95% in service provisioning.  相似文献   

9.
针对现有数据链系统与指控系统间以格式化消息的方式进行交互,系统间耦合紧密,采用广播的方式分发信息,效率不高,与异构数据链系统间信息共享困难等问题,设计并给出了一种面向服务的数据链信息分发系统,详细描述了系统各单元的功能及协作方式。针对分布式环境下,数据链信息服务发现问题,结合现有服务发现的研究成果,分类分析了各算法应用时的优点与不足,在此基础上,给出了下一步研究方向。  相似文献   

10.
一种网格环境的服务查找算法   总被引:4,自引:0,他引:4  
张昕  丁晓宁  金蓓弘  李京 《通信学报》2005,26(12):93-99
网格计算为大规模Internet应用提供了必要的基础架构,服务查找是网格计算的重要研究内容之一。但是目前常见的服务查找算法不太适应于网格环境的分散性和松耦合等特点。提出了一种分布式的、综合考虑网络延迟和节点负载情况及处理能力、适合于网格环境的服务查找算法DDCA。实验结果表明,DDCA算法能有效提高网格环境下应用的整体性能。  相似文献   

11.
12.
    
Various opportunities aimed at the employment of delay-sensitive applications in the vehicular environment are presented by the vehicular cloud (VC). Contrary to diverse wireless networks, VC networks possess exceptional features among others, namely, shorter transmission time along with a higher dynamic topology. Although integration with the cloud offers higher storage along with computation capabilities, it as well entails restricted resource availability. The restrictions on the number of resources serve as a challenge in servicing the applications with their necessary quality of service (QoS) guarantees as the number of service requests for applications keeps on augmenting with diverse circumstances. Thus, the need for an effective scheduling methodology arises to decide the sequence of servicing application requests and successful utilization of a broadcast medium, along with data transmission. To do efficient resource scheduling on VC networks, an optimization algorithm, namely, the crossover and mutation (CM)-centered chicken swarm optimization (CSO) is proposed and implemented with the help of a publicly available dataset. Initially, the VC infrastructure is initialized and some vehicle information is extracted as features. Next, the Brownian motion-centered bacteria foraging optimization (BM-BFO) algorithm chooses the essential features. Centered on the chosen features, the vehicles are clustered using the modified K-means algorithm. Next, as for the cloud server's virtual machines (VMs), the resource information is extracted. Lastly, the CM-CSO algorithm carries out the optimal scheduling in the VC by means of the clustered features of vehicles and features of the VM. The proposed techniques' findings are scrutinized and analogized to the other prevailing methodologies to confirm that the proposed work performs effectively and gives optimal resource allocation (RA) to the VC.  相似文献   

13.
实时可靠地获得全面的车载感知服务信息是车载网络发展的"瓶颈"问题。混杂感知车载网(HSVN)兼有无线传感器网络(WSN)和车载自组网(VANET)的特点,为车载用户提供了大量车载信息,是车载网络的发展趋势。表述性状态转移(REST)架构统一了资源格式和交互形式,在服务器和客户端间进行无状态服务,有利于异构问题的解决。文章基于HSVN的信息服务特征,提出一种新型车载网络框架和服务模型,能提高车载感知信息的服务交互能力;基于REST架构理念,采用HSVN中信息服务资源设计方法,为异构网络下的信息交互系统提供一种轻量化的实现途径。  相似文献   

14.
An Architecture for Secure Wide-Area Service Discovery   总被引:4,自引:0,他引:4  
  相似文献   

15.
嵌入式智能云控制系统的原理与设计   总被引:1,自引:0,他引:1  
云是用语言值表示的某个定性概念与其定量表示之间的不确定性转换模型.基于云模型的定性知识推理,以概念为基本表示,从数据库中挖掘出定性知识,构造规则发生器.多条定性规则构成规则库,当输入一个特定的条件激活多条定性规则时,通过推理引擎,实现带有不确定性的推理和控制.以往实现云控制器,主要依赖计算机及相关软件,限制了其进一步的推广应用.针对基于Quartus Ⅱ设计软件和Nios Ⅱ处理器的可编程片上系统进行设计开发,将云控制器在目标电路板的FPGA芯片中进行系统集成,实现以嵌入式云控制器为核心的智能控制系统,具有接口灵活、扩展性强、便于实现等优点.为基于云模型的智能控制系统的工业化应用,提供了硬件设计基础.  相似文献   

16.
论文在分析数字图书馆云服务相关概念的基础上,探讨了云服务的研究现状,重点介绍了我国高校数字图书馆云服务,在此基础上提出我国高校数字图书馆云服务目前存在的一系列问题,并提出几点建议,以期我国高校数字图书馆云服务更进一层。  相似文献   

17.
随着互联网视频业务爆炸式的增长,建设低成本、高性能、集约化的融合视频平台,并通过网络、系统的弹性伸缩来合理优化系统资源,是当前高速视频增长情况下亟待解决的一个问题.为此,提出了下一代融合视频业务架构,该架构是一种扁平化和全融合的云化架构,能最大程度地降低运营商的运维成本,进一步提升和统一用户体验,并可以灵活地引入丰富的业务,从而为视频业务带来更多的商业前景.  相似文献   

18.
    
Vehicular ad hoc networks (VANETs) are witnessing in recent years a rapid development for road transmissions and are considered as one of the most important types of next generation networks, in which drivers can have access anywhere and anytime to information. However, vehicles have to deal with many challenges such as the links failures due to their frequent mobility as well as limited degrees of freedom in their mobility patterns. In this paper, we propose a new quality of service multicast and multipath routing protocol for VANETs, based on the paradigm of bee's communication, called multicast quality of service swarm bee routing for VANETs (MQBV). The MQBV finds and maintains robust routes between the source node and all multicast group members. Therefore, the average end‐to‐end delay and the normalized overhead load should be reduced, while at the same time increasing the average bandwidth and the packet delivery ratio. Extensive simulation results were obtained using ns‐2 simulator in a realistic VANET settings and demonstrated the efficiency of the proposed protocol. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
随着数字家电的普及,家庭网络技术呈现出越来越广阔的市场应用前景。为了实现家庭网络互联设备的操作控制和信息共享,需要采用通用即插即用(UPnP)技术。UPnP充分重用包括IP、传输控制协议(TCP)、数据报协议(UDP)、超文本传输协议(HTTP)和可扩展标记语言(XML)在内的互联网技术标准,提供服务的跨平台自动发现和远程控制。采用UPnP可实现灵活而强大的业务发现能力,能将复杂的网络设备驱动变为简单的远程网络控制,同时还能提供互联设备的操作控制和信息共享。  相似文献   

20.
盛国军  温涛  郭权  宋晓莹 《通信学报》2013,34(10):37-48
针对非结构化P2P网络中的服务发现问题,提出了一种基于改进蚁群算法的可信服务发现方法。该方法在传统蚁群算法基础上应用若干新的策略控制蚁群的行为,如动态蚁群策略、子蚂蚁策略、服务节点的信誉评估策略以及蚂蚁的恶意节点惩罚策略等, 高信誉服务节点在蚂蚁的推荐下进行邻居更换和自组织。 这些策略和方法为蚁群算法在分布式环境下服务发现的应用研究提供了一种新思路。实验结果表明, 本算法在各种常见复杂网络环境下仍可保证较高的可信服务查准率和更高的综合服务发现效率, 通过对实验数据的分析和解释得到了若干有益的结论,为进一步的研究工作奠定了基础。  相似文献   

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