基于流行病理论的无线认知传感网抗攻击模型

大量无线通信设备在ISM频段工作致使免许可频段频谱资源稀缺,促使认知无线电和无线传感器网络（WSN）融合,形成无线认知传感器网络（WCSN）。文章研究了无线认知传感器网络中的数据伪造攻击,即恶意次用户通过向其他次用户发送伪造的频谱感知数据,导致控制中心做出错误的频谱分配决策。基于流行病理论,文章对数据伪造攻击中的信息传播过程进行了建模和分析,找出了决定无线认知传感器网络中潜在流行病爆发的关键因素。最后,通过仿真实验,对模型进行了验证,并对系统动态特性进行了研究。     

智能电网WCSN安全体系架构研究

作为下一代电力系统,智能电网应具备向电网控制中心实时可靠传输信息的能力。为了解决智能电网无线传感器网络面临的异构无线网络共存、频谱资源紧张和海量数据处理等问题,我们在智能电网引入了无线认知传感器网络的理念。文章分析了在智能电网中引入认知无线传感器网络（WCSN）的必要性,列举了智能电网、认知无线电网络和无线传感器网络的相关研究成果,描述了智能电网WCSN分层结构包括家域网、邻域网和广域网,提出了智能电网WCSN安全架构。     

一种对抗无线认知传感器网络攻击的分布式防护研究

该文提出了在无线认知传感器网络（WCSN）中不采用任何防护措施的情况下,网络极易受到流量注入攻击的问题,通过对无线认知传感器网络（WCSN）中流量注入攻击方式的研究,提出了一种分布式防护方案,并对方案进行了详细分析。     

WSN中入侵节点检测的节点测距方法

提出基于节点测距的无线传感器网络（WSN）入侵节点检测算法,用于检测无线传感器网络中是否存在外来的伪造节点。该算法运用节点自身的各种传感器进行节点间测距,通过综合分析测距结果保证该算法能成功检测到网络中存在的伪造节点,检测中不需要网络同步时钟和节点位置信息。该算法可适用于不同规模、不同应用的无线传感器网络。通过理论分析和仿真实验验证了该算法在无线传感器网络节点攻击检测中的有效性和可行性。     

认知物联网频谱感知数据伪造攻击研究

认知物联网可以看作是＂认知无线电传感器节点的分布式网络＂,它通过在物联网中实现认知无线电技术,可以有效地解决物联网面临的频谱资源紧张等问题。文章提出了认知物联网的基本定义和体系结构,设计了频谱感知数据伪造（SSDF）攻击模型,分析了基于数据融合、基于一致性、基于SVDD算法、基于异常值检测等四种解决方案的原理与性能。     

传感器网络中基于时钟偏移的伪造节点攻击检测技术

研究一种基于时钟偏移的传感器网络中伪造节点攻击被动式检测技术。以节点之间的时钟同步数据作为输入,构建相对发送/接收时间差序列,提取数据发送源的相对时钟偏移。在此基础上,提出了DSNA（detect spoofed node attack）算法,通过检测相对发送/接收时间差序列异常识别伪造节点攻击,进一步在确定了攻击模式的基础上,对不同节点所发送的同步数据进行分类并提取时钟偏移作为指纹识别出伪造节点。在真实传感器网络环境下对检测技术进行了验证,结果表明该方法可以在被动方式下,快速准确地实现对伪造节点攻击的检     

无线认知传感器网络的研究

在无线传感器网络中引入认知无线电技术,构成无线认知传感器网络,可以减少ISM频段干扰,提高数据传输率。对无线认知传感器网络的研究目前已成为一个新的研究领域。介绍了无线认知传感器网络的概念,从无线认知传感器网络的节点、频谱感知、频谱决策、频谱共享、频谱迁移、网络层、传输层、应用层等方面综述了现有的研究成果,讨论了目前存在的问题和需要进一步研究的方向。     

面向拜占庭攻击的认知用户分类

万物互联的蓬勃发展使得承载业务的无线资源日益短缺,认知无线电技术是具有广大前景的技术。而作为实现认知无线电的基础环节的频谱感知却面临特有的安全威胁,其中拜占庭攻击伪造频谱感知数据,利用认知网络的开放性和合作机制,恶意篡改上传数据,致使融合中心做出错误判断,造成频谱资源损失。因此,针对拜占庭攻击下的安全问题,该文提出了基于图神经网络的异常度检测,依据图神经网络得到数据异常程度,结合全局判决与邻居用户冲突程度建立异常度模型。首先,介绍了认知网络频谱感知的相关原理;接着,展示了认知网络的模型,并对拜占庭攻击做了简单的概括。研究结果表明,该算法在拜占庭攻击中取得优异的识别性能,不仅降低了正常用户的误判概率,同时提高了恶意用户的检测概率。     

无线传感器网络中恶意程序的传播模型

由复杂网络理论得出一种无线传感器网络的模型,结合IEEE 802.15.4标准及流行病学理论,综合考虑目前传感器网络通过节点休眠与唤醒机制来节约能耗,提出一种无线传感器网络中恶意程序传播的SIR/WS模型。该模型描述了感染节点以广播方式传播恶意程序的过程,发现提高免疫率及降低传染率均可抑制恶意程序在无线传感器网络中的传播。仿真结果表明,该模型能较好地描述无线传感器网络中恶意程序的传播特性。     

基于无线传感器网络的信誉形式化模型

无线传感器网络的安全威胁不仅发生在节点之间传递信息的时候,还发生在节点产生信息的时候,因此,单靠密码学和认证无法阻止传感器网络内部的攻击以及节点的异常行为.本文提出了一种基于无线传感器网络的信誉形式化模型,该模型形式化地描述了传感器节点信誉的表示、更新和整合.同时,通过对信誉分布和β分布的拟合分析与推理,发现β分布可以很好地描述与实现上述方案,由此设计了一个基于β分布的无线传感器网络信誉系统实例.实验表明,本信誉方案有较好的稳定性,能够抵抗诽谤攻击和信誉欺骗攻击,很好地解决无线传感器网络对数据认证的需求.     

A survey on cyber attacks against nonlinear state estimation in power systems of ubiquitous cities

It is well-known that critical infrastructures would be targets for cyber attacks. In this paper, we focus on the power systems (i.e. smart grids) in ubiquitous cities, where every meter is linked to an information network through wireless networking. In a smart grid system, information from smart meters would be used to perform a state estimation in real time to maintain the stability of the system. A wrong estimation may lead to disastrous consequences (e.g. suspension of electricity supply or a big financial loss). Unfortunately, quite a number of recent results showed that attacks on this estimation process are feasible by manipulating readings of only a few meters. In this paper, we focus on nonlinear state estimation which is a more realistic model and widely employed in a real power grid environment. We category cyber attacks against nonlinear state estimation, and review the mechanisms behind. State-of-the-art security measures to detect these attacks are discussed via sensor protection. Hope that the community would be able to come up with a secure system architecture for ubiquitous cities.     

基于贝叶斯序贯博弈模型的智能电网信息物理安全分析

智能电网是利用信息技术优化从供应者到消费者的电力传输和配电网络.作为一种信息物理系统（Cyber-physical system,CPS）,智能电网由物理设备和负责数据计算与通信的网络组成.智能电网的诸多安全问题会出现在通信网络和物理设备这两个层面,例如注入坏数据和收集客户隐私信息的网络攻击,攻击电网物理设备的物理攻击等.本文主要研究了智能电网的系统管理员（防护者）如何确定攻击者类型,从而选择最优防护策略的问题.提出了一种贝叶斯序贯博弈模型以确定攻击者的类型,根据序贯博弈树得到博弈双方的均衡策略.首先,对类型不确定的攻击者和防护者构建静态贝叶斯博弈模型,通过海萨尼转换将不完全信息博弈转换成完全信息博弈,得到贝叶斯纳什均衡解,进而确定攻击者的类型.其次,考虑攻击者和防护者之间的序贯博弈模型,它能够有效地帮助防护者进行决策分析.通过逆向归纳法分别对两种类型的攻击者和防护者之间的博弈树进行分析,得到博弈树的均衡路径,进而得到攻击者的最优攻击策略和防护者的最优防护策略.分析表明,贝叶斯序贯博弈模型能够使防护者确定攻击者的类型,并且选择最优防护策略,从而为涉及智能电网信息安全的相关研究提供参考.     

智能电网容错数据聚合方案

新一代智能电网的出现,极大地提升了电网的安全性与可靠性,这依赖于智能电表每15分钟发送一次数据,但是这可能会暴露用户的隐私,同时需要消耗很大的计算代价.于是数据聚合技术被引入,大多数现有聚合方案存在耗时大且当电表故障时系统无法正常运行等问题.针对上述问题,本文提出了一个智能电网中高效的支持错误容忍的数据聚合方案,具体来...     

Supply chain intelligence for electricity markets: A smart grid perspective

Smart grid technologies are bringing innovations in electrical power industries, affecting all parts of the electricity supply chain, and leading to changes in market structure, business models and services. In this paper we introduce a model of business intelligence for a smart grid supply chain. The model is developed in order to provide electricity markets with the necessary data flows and information important for the decision making process. The proposed model offers a way to efficiently leverage the new metering architecture and the new capabilities of the grid to reap immediate business value from the huge amounts of disparate data in emerging smart grids. The model was evaluated for the Serbian electricity market in the electric power transmission company Public Enterprise “Elektromre?a Srbije”. The results show that business intelligence solutions can contribute to a more effective management of smart grids, in order to ensure that companies achieve sustainability in the increasingly competitive electricity markets, while still providing the high quality services to end users.     

Cyber Attack Protection and Control of Microgrids

Recently, the smart grid has been considered as a next-generation power system to modernize the traditional grid to improve its security, connectivity, efficiency and sustainability. Unfortunately, the smart grid is susceptible to malicious cyber attacks, which can create serious technical, economical, social and control problems in power network operations. In contrast to the traditional cyber attack minimization techniques, this paper proposes a recursive systematic convolutional (RSC) code and Kalman filter (KF) based method in the context of smart grids. Specifically, the proposed RSC code is used to add redundancy in the microgrid states, and the log maximum a-posterior is used to recover the state information, which is affected by random noises and cyber attacks. Once the estimated states are obtained by KF algorithm, a semidefinite programming based optimal feedback controller is proposed to regulate the system states, so that the power system can operate properly. Test results show that the proposed approach can accurately mitigate the cyber attacks and properly estimate and control the system states.      

On modeling of electrical cyber-physical systems considering cyber security

This paper establishes a new framework for modeling electrical cyber-physical systems (ECPSs), integrating both power grids and communication networks. To model the communication network associated with a power transmission grid, we use a mesh network that considers the features of power transmission grids such as high-voltage levels, long-transmission distances, and equal importance of each node. Moreover, bidirectional links including data uploading channels and command downloading channels are assumed to connect every node in the communication network and a corresponding physical node in the transmission grid. Based on this model, the fragility of an ECPS is analyzed under various cyber attacks including denial-of-service (DoS) attacks, replay attacks, and false data injection attacks. Control strategies such as load shedding and relay protection are also verified using this model against these attacks.     

认知无线电网络中安全的协作频谱检测算法

在认知无线电网络中,当认知用户存在虚假感知信息SSDF时,协作频谱感知的性能会受到巨大影响。为了确保频谱感知的鲁棒性,提出了一种基于信誉度加权序贯频谱检测算法来识别恶意用户并减轻他们造成的影响。该算法通过使用认知用户的近期感知信息计算本地信誉度函数,再综合考虑其信誉值与感知过程中表现的稳定程度以消除恶意用户对主用户的传输效率带来的影响。仿真结果表明,在恶意攻击环境下,新算法优于现有典型协作频谱感知算法。     

The role of communication systems in smart grids: Architectures,technical solutions and research challenges

The purpose of this survey is to present a critical overview of smart grid concepts, with a special focus on the role that communication, networking and middleware technologies will have in the transformation of existing electric power systems into smart grids. First of all we elaborate on the key technological, economical and societal drivers for the development of smart grids. By adopting a data-centric perspective we present a conceptual model of communication systems for smart grids, and we identify functional components, technologies, network topologies and communication services that are needed to support smart grid communications. Then, we introduce the fundamental research challenges in this field including communication reliability and timeliness, QoS support, data management services, and autonomic behaviors. Finally, we discuss the main solutions proposed in the literature for each of them, and we identify possible future research directions.     

基于联盟区块链的智能电网数据安全存储与共享系统

智能电网为了实现电网可靠、安全、高效地运行,需要广泛部署无线传感网络（WSN）监控电网状态,并及时对电网异常情况进行处理。在现有的智能电网中,WSN的感知数据需要上传到可信的中心节点进行存储与共享,但是这种中心化的存储方式容易引起中心节点遭受恶意攻击而发生单点失效、数据被故意篡改等信息安全问题。针对这些信息安全问题,利用新兴的联盟区块链技术在智能电网中选定若干数据采集基站,组成智能电网数据存储联盟链（DSCB）系统。DSCB中节点间数据共享通过智能合约的方式来完成,数据拥有者设定数据共享的约束条件,使用计算机语言代替法律条款来规范数据访问者行为,从而实现以去中心化的方式集体维护一个安全可靠的数据存储数据库。安全分析表明所提数据存储联盟链系统能实现安全、有效的数据存储与共享。