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1.
A Study of Path Protection in Large-Scale Optical Networks   总被引:1,自引:1,他引:0  
We consider the problem of designing a network of optical cross-connects (OXCs) which provides end-to-end lightpath services to large numbers of client nodes, under the requirement that the network will survive any single-link failure. Our main objective is to quantify the additional resource requirements of implementing path protection schemes over a network with no survivability properties. To this end, we present heuristic routing and wavelength assignment algorithms for dedicated path protection and two variants of shared path protection, and integrate them into the physical and logical topology design framework we developed in an earlier study. We apply our heuristics to networks with up to 1000 client nodes, with a number of lightpaths that is an order of magnitude greater than the number of clients, and for a wide range of values for system parameters such as the number of wavelengths per fiber, the number of optical transceivers per client node, and the number of ports per OXC. Our results provide insight into the relative resource requirements of dedicated and shared path protection schemes. We also find that, using shared path protection schemes, it is possible to build cost-effective survivable networks that provide rich connectivity among client nodes with only a modest additional amount of resources over a network with no survivability properties.  相似文献   

2.
MANNA: a management architecture for wireless sensor networks   总被引:10,自引:0,他引:10  
Wireless sensor networks (WSNs) are becoming an increasingly important technology that will be used in a variety of applications such as environmental monitoring, infrastructure management, public safety, medical, home and office security, transportation, and military. WSNs will also play a key role in pervasive computing where computing devices and people are connected to the Internet. Until now, WSNs and their applications have been developed without considering a management solution. This is a critical problem since networks comprising tens of thousands of nodes are expected to be used in some of the applications above. This article proposes the MANNA management architecture for WSNs. In particular, it presents the functional, information, and physical management architectures that take into account specific characteristics of this type of network. Some of them are restrict physical resources such as energy and computing power, frequent reconfiguration and adaptation, and faults caused by nodes unavailable. The MANNA architecture considers three management dimensions: functional areas, management levels, and WSN functionalities. These dimensions are specified to the management of a WSN and are the basis for a list of management functions. The article also proposes WSN models to guide the management activities and the use of correlation in the WSN management. This is a first step into a largely unexplored research area.  相似文献   

3.
Optimizing sensor networks in the energy-latency-density design space   总被引:5,自引:0,他引:5  
In wireless sensor networks, energy efficiency is crucial to achieving satisfactory network lifetime. To reduce the energy consumption significantly, a node should turn off its radio most of the time, except when it has to participate in data forwarding. We propose a new technique, called sparse topology and energy management (STEM), which efficiently wakes up nodes from a deep sleep state without the need for an ultra low-power radio. The designer can trade the energy efficiency of this sleep state for the latency associated with waking up the node. In addition, we integrate STEM with approaches that also leverage excess network density. We show that our hybrid wakeup scheme results in energy savings of over two orders of magnitude compared to sensor networks without topology management. Furthermore, the network designer is offered full flexibility in exploiting the energy-latency-density design space by selecting the appropriate parameter settings of our protocol.  相似文献   

4.
基于互操作计算的SBDM设备管理模型的研究   总被引:6,自引:1,他引:5  
普适计算时代,各种嵌入式Internet设备将被嵌入到人们的生活空间中。然而,由于它们支持各不相同的管理协议,很难进行统一管理。对此,首先提出了一种嵌入式Internet设备互操作机制——服务共享机制,并描述了其基本概念、体系结构、ICS协议栈和服务访问过程。然后在此基础上提出了一个设备管理模型SBDM,把用户和设备厂商从传统设备管理模型存在的功能与协议的纠缠问题中释放出来。最后,设计实现了一个SBDM应用框架,对其进行了验证。  相似文献   

5.
If current trends continue, the next generation of enterprise networks is likely to become a more complex mixture of hardware, communication media, architectures, protocols, and standards. One approach toward reducing the management burden caused by growing complexity is to integrate management support into the inherent function of network operation. In this paper, management support is provided in the form of network components that, simultaneously with their network function, collaboratively project and adjust projections of future state based upon actual network state. It is well known that more accurate predictions over a longer time horizon enables better control decisions. This paper focuses upon improving prediction; the many potential uses of predictive capabilities for predictive network control will be addressed in future work.  相似文献   

6.
The technological integration of the Internet of Things (IoT)-Cloud paradigm has enabled intelligent linkages of things, data, processes, and people for efficient decision making without human intervention. However, it poses various challenges for IoT networks that cannot handle large amounts of operation technology (OT) data due to physical storage shortages, excessive latency, higher transfer costs, a lack of context awareness, impractical resiliency, and so on. As a result, the fog network emerged as a new computing model for providing computing capacity closer to IoT edge devices. The IoT-Fog-Cloud network, on the other hand, is more vulnerable to multiple security flaws, such as missing key management problems, inappropriate access control, inadequate software update mechanism, insecure configuration files and default passwords, missing communication security, and secure key exchange algorithms over unsecured channels. Therefore, these networks cannot make good security decisions, which are significantly easier to hack than to defend the fog-enabled IoT environment. This paper proposes the cooperative flow for securing edge devices in fog-enabled IoT networks using a permissioned blockchain system (pBCS). The proposed fog-enabled IoT network provides efficient security solutions for key management issues, communication security, and secure key exchange mechanism using a blockchain system. To secure the fog-based IoT network, we proposed a mechanism for identification and authentication among fog, gateway, and edge nodes that should register with the blockchain network. The fog nodes maintain the blockchain system and hold a shared smart contract for validating edge devices. The participating fog nodes serve as validators and maintain a distributed ledger/blockchain to authenticate and validate the request of the edge nodes. The network services can only be accessed by nodes that have been authenticated against the blockchain system. We implemented the proposed pBCS network using the private Ethereum 2.0 that enables secure device-to-device communication and demonstrated performance metrics such as throughput, transaction delay, block creation response time, communication, and computation overhead using state-of-the-art techniques. Finally, we conducted a security analysis of the communication network to protect the IoT edge devices from unauthorized malicious nodes without data loss.  相似文献   

7.
Next-generation optical networks as a value creation platform   总被引:1,自引:0,他引:1  
In this article we discuss the role of the next-generation optical networks and introduce enabling technologies that support network evolution. The role of networks is undergoing change and is becoming a platform for value creation. In addition to providing new services, networks have to accommodate steady traffic growth and guarantee profitability. We envision a next-generation optical network as the combination of an all-optical core and an adaptive shell operated by intelligent control and management software suites. Possible technological innovations are introduced in devices, transmission technologies, nodes, and networking software, which will contribute to attain a flexible and cost-effective next-generation optical network. New values will be created by the new services provided through these networks, which will change the ways we do businesses and go about our private lives.  相似文献   

8.
Using the existing home infrastructure based on open industry standards, we will be able to integrate the home network with external networks to easily manage home devices, both locally and remotely. The advent of pervasive computing marks an urgent need for a new generation of intelligent sensing agents and information appliances. It will also demand environments for resource management of broad applications involving loosely coupled, event-driven, diverse information appliances. It is suggested that the development of intelligent sensing agents and sensor-based information appliances will spread pervasive technology to a multitude of human activities such as mining and manufacturing, security, transportation, sports, and health care. The topics discussed also include management of heterogeneous functions and networking technologies.  相似文献   

9.
The concept of Internet of Things (IoT) was first proposed by MIT Prof.Kevin Ash-ton in 1999.The implementation of IoT was mainly through RFID in its early time.With advanced technology and manufacture,diverse implementation forms ofIoT are becoming possible.Wearable devices,as an essential branch of IoT,will have broad application prospects in health monitoring and intelligent healthcare.  相似文献   

10.
Ad-hoc networks do not rely on a pre-installed infrastructure, but they are formed by end-user devices in a self-organized manner. A consequence of this principle is that end-user devices must also perform routing functions. However, end-user devices can easily be compromised, and they may not follow the routing protocol faithfully. Such compromised and misbehaving nodes can disrupt routing, and hence, disable the operation of the network. In order to cope with this problem, several secured routing protocols have been proposed for ad-hoc networks. However, many of them have design flaws that still make them vulnerable to attacks mounted by compromised nodes. In this paper, we propose a fully automatic verification method for secure ad-hoc network routing protocols that helps increasing the confidence in a protocol by providing an analysis framework that is more systematic, and hence, less error-prone than the informal analysis. Our method is based on a deductive proof technique and a backward reachability approach. The main novelty of this approach compared to the prior works is that beside providing expressive semantics and syntax for modelling and specifying secure routing protocols, it assumes an arbitrary topology, and a strong attacker model.  相似文献   

11.
Data/content dissemination among the mobile devices is the fundamental building block for all the applications in wireless mobile collaborative computing, known as mobile peer‐to‐peer. Different parameters such as node density, scheduling among neighboring nodes, mobility pattern, and node speed have a tremendous impact on data diffusion in a mobile peer‐to‐peer environment. In this paper, we develop analytical models for object diffusion time/delay in a wireless mobile network to apprehend the complex interrelationship among these different parameters. In the analysis, we calculate the probabilities of transmitting a single object from one node to multiple nodes using the epidemic model of spread of disease. We also incorporate the impact of node mobility, radio range, and node density in the networks into the analysis. Utilizing these transition probabilities, we estimate the expected delay for diffusing an object to the entire network both for single object and multiple object scenarios. We then calculate the transmission probabilities of multiple objects among the nodes in the wireless mobile network considering network dynamics. Through extensive simulations, we demonstrate that the proposed scheme is efficient for data diffusion in the wireless mobile network. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

12.
Real-time payments for mobile IP   总被引:2,自引:0,他引:2  
The mobile IP protocol has evolved from providing mobility support for portable computers to support for wireless handheld devices with high mobility patterns. A new category of micromobility protocols has been proposed to deal with the increased signaling loads that will be generated with large populations of such devices on a network. We argue that the authentication schemes presently employed in these networks do not scale well for large numbers of nodes, and that the lack of accounting procedures prevents the mass deployment of these networks. We envisage that future access networks will be operated by independent service providers, who will charge users for access to services in the fixed network but may not have long-term contractual relationships with them. These access networks may also employ a variety of micromobility protocols for fast handover support. We present a scheme based on hash chains, which allows for fast authentication of datagrams for secure updating of router entries within the access network, and real-time accounting of network usage by mobile nodes. Such a system will alleviate problems of fraud in mobile networks and eliminate the need for interoperator billing agreements.  相似文献   

13.
Trust management is a promising approach to conduct nodes’ transactions and establish management interactions in mobile ad hoc networks, in which collaboration between nodes is critical to achieve system goals. Lack of centralized management, severe resource constraints (e.g. computing power, energy, bandwidth), and important network dynamics (e.g. topology changes, node mobility, node failure, propagation channel conditions) make the trust management a challenging task in such a network. Mainly, trust management frameworks are prone to attacks trying to deceive nodes’ estimation on other nodes’ trustworthiness, referred to as trust-distortion attacks. In order to inhibit such attacks, we propose a Trust-distortion Resistant Trust Management Scheme (TRTMS) which provides nodes with an accurate estimation on other nodes’ behavior and enables them to handle different trust-distortion attacks in a multi-attack environment. Simulation results prove that TRTMS significantly outperforms the existing alternatives in the literature in presence of simultaneous and contradictory different trust-distortion attacks.  相似文献   

14.
针对我国航天测控网设备状态配置和管理方法现状,分析了测控设备任务准备和历史任务恢复节点的现实需要,提出了航天测控设备历史状态宏迁移、设备参数共享以及设备状态集中管理3种方法。通过分析比较,给出了设备状态集中管理和可扩展标记语言( XML)格式设备状态共享方法相结合的实现途径。该方法能够实现设备参数的快速设置和检查以及不同设备之间状态的共享,有利于提高整个测控网的自动化程度和运行效率。  相似文献   

15.
Optical burst switching realizes all-optical communication by dividing data transmission system into control plane and data plane. In order to implement control plane two controlling mechanisms such as distributed and centralized control and reservation models have been presented in literature. Both of the architectures have pros and cons associated such as distributed model lacks efficient resource utilization while centralized model is nonscalable. In order to overcome these, a new hybrid control and reservation mechanism has been presented by the authors. The proposed model is based on clustering technique where each cluster consists of cluster head and member nodes. Cluster head performs major functionalities in the network such as path establishment, routing and resource management, fault management, etc., while member nodes perform data switching functionality. In order to implement the architecture, a signaling protocol is also presented. In this paper, we discuss different scenarios required for the implementation of the proposed hybrid model. These scenarios detail the message dialogs exchange between different network nodes and between different software modules during lightpath establishment, data transmission, and connection teardown operations. The goal of efficient resource utilization is achieved through centralized control of network resources while scalability is achieved through dividing the network into multiple domains. Finally, the simulation section shows the mechanism of designing the multidomain architecture, network bandwidth utilization comparison and reduction in end-to-end data transmission latency.   相似文献   

16.
A personal network (PN) is a network of devices belonging to a person. It can consist of a number of ad hoc sub-networks which are linked together through the Internet. We study battery-aware routing for multi-hop connectivity in sub-networks of PNs, and propose a new algorithm. The proposed algorithm takes the advantage of having mains-connected devices in a PN to direct the traffic to such devices and avoid relaying over nodes with low battery energy. A consequence of this strategy is directing the traffic load to static nodes of the network as well, since mains-connected nodes are static while battery-powered nodes could be mobile. This results in less route failures due to less mobility of nodes along a chosen path. We comprehensively compare the performance of our proposed algorithm with the performance of some well-known algorithms from the literature. We consider the effect of node density, routing overhead, heterogeneity of nodes in terms of their power supplies, gateway-oriented communication, mobility of nodes, and transmission power control, on the performance of battery-aware routing algorithms in PNs. Taking into account various parameters and different scenarios, we show that directing the traffic to mains-powered nodes can profoundly increase operational lifetime of the network. Our algorithm, as well as the results of our work, can also be applied to other types of ad hoc networks with heterogeneous power supplies.  相似文献   

17.
胡颖  庄雷  陈鸿昶  马丁 《通信学报》2016,37(6):106-118
针对虚拟网的节能映射问题,建立了结合时间和能量感知的虚拟网映射算法。在对节点和路径的评价标准中加入了时间因素,综合考虑了物理资源的运行时间等因素,用概率理论辅助分析了每个虚拟节点的多个可用物理节点被选中的概率。在节点选择阶段,综合考虑底层节点的剩余资源量、CPU资源利用率增量、节点开启情况和是否延长使用时间等因素,并使用条件概率理论辅助分析得到各可用节点的重要性;在链路选择阶段,综合考虑链路开启情况、延长使用时间和链路长度等因素。不仅使虚拟网请求映射在当前较小的节点和链路集合中,而且映射到了延长时间较短的设备上。实验结果表明,与未考虑时间因素的方法相比,该方法能带来更好的性能和更低的能耗。  相似文献   

18.
In this paper, we present an optical network demonstrator realizing a wavelength division multiplexing (WDM) metropolitan self-healing ring. The network integrate three optical add-drop multiplexer (OADM) nodes, designed by two manufacturing companies adopting different architectures and technological solution. It is so demonstrated that transversal compatibility among optical network entities produced by different companies is possible at the state of the art of the technology. A complete transmission performance characterization of the network has been carried out demonstrating that, in nominal operating conditions and on the most critical path, the error probability is lower that 10-14. The reconfiguration times in case of failure has been measured too, demonstrating that this network architecture provide fast self-healing mechanism, in line with the requirements of ITU-T recommendations for very high capacity networks  相似文献   

19.
社交物联网是社交网络概念在物联网中整合后兴起的一个蓬勃发展的研究领域.提出了一种适用于社交物联网网络的改进型节点级信任模型,并通过与其他信任模型的对比仿真实验证明在恶意节点的攻击下,提出的模型拥有更好的稳定性和适用性,总体波动较小.同时,针对实际社交物联网网络中新加入网络的陌生节点可能遇到的网络延迟影响信任值评估的问题...  相似文献   

20.
Wireless sensor networks have found their way to countless applications in many different fields. Due to the restricted power availability these systems are faced with, custom wireless protocols have been designed. Many different protocols have already been conceived, yet each application will impose different requirements. In inertial motion tracking, sensor nodes are applied on the body allowing full body posture reconstruction. These nodes must not hinder or restrict the movements of the user in any way, meaning that a wireless approach is desirable. A suiting protocol that insures robust simultaneous functionality of at least 15 nodes at a rate of 100Hz is required. A TDMA based protocol with master/slave hierarchy is presented for the application at hand. Nodes dynamically decide on their role within the network at startup and reassess the network state regularly. Conflicting situations are handled whenever they arise and nodes react accordingly creating a fully plug-and-play system. Careful implementation of the protocol in embedded software allows data transmission of 19 nodes while each of them consumes an average current of only 3mA.  相似文献   

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