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Dynamic Security SFC Branching Path Selection Using Deep Reinforcement Learning

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Intelligent Automation & Soft Computing 2023年第9期37卷 2919-2939页

作者： Shuangxing Deng Man Li huachun zhou School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China

Security service function chaining(SFC)based on software-defined networking(SDN)and network function virtualization(NFV)technology allows traffic to be forwarded sequentially among different security service functions to achieve a combination of security functions.Security SFC can be deployed according to requirements,but the current SFC is not flexible enough and lacks an effective feedback mechanism.The SFC is not traffic aware and the changes of traffic may cause the previously deployed security SFC to be invalid.How to establish a closed-loop mechanism to enhance the adaptive capability of the security SFC to malicious traffic has become an important issue.Our contribution is threefold.First,we propose a secure SFC path selection framework.The framework can accept the feedback results of traffic and security service functions in SFC,and dynamically select the opti-mal path for SFC based on the feedback results.It also realizes the automatic deployment of paths,forming a complete closed loop.Second,we expand the protocol of SFC to realize the security SFC with branching path,which improve flexibility of security SFC.Third,we propose a deep reinforcement learning-based dynamic path selection method for security SFC.It infers the optimal branching path by analyzing feedback from the security SFC.We have experimented with Distributed Denial of Service(DDoS)attack detection modules as security service functions.Experimental results show that our proposed method can dynamically select the optimal branching path for a security SFC based on traffic features and the state of the SFC.And it improves the accuracy of the overall malicious traffic detection of the security SFC and significantly reduces the latency and overall load of the SFC.

关键词： Service function chaining deep reinforcement learning security service

Multi-Domain Malicious Behavior Knowledge Base Framework for Multi-Type DDoS Behavior Detection

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Intelligent Automation & Soft Computing 2023年第9期37卷 2955-2977页

作者： Ouyang Liu Kun Li Ziwei Yin Deyun Gao huachun zhou School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China

Due to the many types of distributed denial-of-service attacks(DDoS)attacks and the large amount of data generated,it becomes a chal-lenge to manage and apply the malicious behavior knowledge generated by DDoS attacks.We propose a malicious behavior knowledge base framework for DDoS attacks,which completes the construction and application of a multi-domain malicious behavior knowledge base.First,we collected mali-cious behavior traffic generated by five mainstream DDoS attacks.At the same time,we completed the knowledge collection mechanism through data pre-processing and dataset design.Then,we designed a malicious behavior category graph and malicious behavior structure graph for the characteristic information and spatial structure of DDoS attacks and completed the knowl-edge learning mechanism using a graph neural network model.To protect the data privacy of multiple multi-domain malicious behavior knowledge bases,we implement the knowledge-sharing mechanism based on federated learning.Finally,we store the constructed knowledge graphs,graph neural network model,and Federated model into the malicious behavior knowledge base to complete the knowledge management mechanism.The experimental results show that our proposed system architecture can effectively construct and apply the malicious behavior knowledge base,and the detection capability of multiple DDoS attacks occurring in the network reaches above 0.95,while there exists a certain anti-interference capability for data poisoning cases.

关键词： DDoS attack knowledge graph multi-domain knowledge base graph neural network federated learning

Acceptance and Factors Associated With Participation in Functional Cure–Related Trials Among People Living With HIV: A Cross-sectional Study in Southern China

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Infectious Microbes & Diseases 2024年第1期6卷 11-19页

作者： Zhaomin Deng Minjuan Shi Yue Yuan GuangjinCao Chunyan Wen Lijuan Chen Xueying Fan Linan Wu Jianhui Yuan huachun Zou Linghua Li Caijun Sun School of Public Health(Shenzhen) Shenzhen Campus of Sun Yat-sen UniversityShenzhenChina Department of Diseases Control Panyu District Center for Disease Control and PreventionGuangzhouChina Infectious Disease Center Guangzhou Eighth People's HospitalGuangzhou Medical UniversityGuangzhouChina Nanshan District Center for Disease Control and Prevention ShenzhenChina Key Laboratory of Tropical Disease Control(Sun Yat-sen University) Ministry of EducationGuangzhouChina

HIV remains a global health challenge,and research efforts directed towards a functional cure require people living with HIV(PLHIV)in-volvement in clinical trials.Our study assessed willingness to participate in HIV functional cure–related clinical trials and associated factors among PLHIV in Guangzhou,China,using a questionnaire survey approach.We analyzed responses from 718 questionnaires,finding that 71.2%were willing to participate in Phase Ⅲtrials,while 51.7%were willing to participate in Phase I trials and 42.9%expressed acceptability for analytic treatment interruption.Multivariate logistic regression demonstrated that male PLHIV,those with awareness of functional cure,and PLHIV,who had been on antiretroviral therapy(ART)for less than 1 year,were more willing to partic-ipate in Phase Ⅲtrials.Those with a body mass index greater than 24,and those without resistance to ART drug were more willing to participate in Phase I trials.The major motivations for participation in Phase Ⅲtrials were access to cutting-edge treatments(62.6%)and supporting research(55.3%).Safety was the main concern contributing to hesitancy.Our study revealed a high willingness to participate in HIV functional cure–related trials among PLHIV in Guangzhou,China,and willingness varied across different trial phases and was influenced by multiple factors.This study provides valuable references for future clinical trial recruitment strategies and public health policy formulation.

关键词： people living with HIV functional cure clinical trials willingness

Application of Neural Network in Fault Location of Optical Transport Network

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China Communications 2019年第10期16卷 214-225页

作者： Tianyang Liu Haoyuan Mei Qiang Sun huachun zhou School of Electronic and Information Engineering Beijing Jiaotong University

Due to the increasing variety of information and services carried by optical networks, the survivability of network becomes an important problem in current research. The fault location of OTN is of great significance for studying the survivability of optical networks. Firstly, a three-channel network model is established and analyzing common alarm data, the fault monitoring points and common fault points are carried out. The artificial neural network is introduced into the fault location field of OTN and it is used to judge whether the possible fault point exists or not. But one of the obvious limitations of general neural networks is that they receive a fixedsize vector as input and produce a fixed-size vector as the output. Not only that, these models is even fixed for mapping operations (for example, the number of layers in the model). The difference between the recurrent neural network and general neural networks is that it can operate on the sequence. In spite of the fact that the gradient disappears and the gradient explodes still exist in the neural network, the method of gradient shearing or weight regularization is adopted to solve this problem, and choose the LSTM (long-short term memory networks) to locate the fault. The output uses the concept of membership degree of fuzzy theory to express the possible fault point with the probability from 0 to 1. Priority is given to the treatment of fault points with high probability. The concept of F-Measure is also introduced, and the positioning effect is measured by using location time, MSE and F-Measure. The experiment shows that both LSTM and BP neural network can locate the fault of optical transport network well, but the overall effect of LSTM is better. The localization time of LSTM is shorter than that of BP neural network, and the F1-score of LSTM can reach 0.961566888396156 after 45 iterations, which meets the accuracy and real-time requirements of fault location. Therefore, it has good application prospect and practical value to introduce neural networ

关键词： optical transport networks failure localization artificial neural network longshort term memory network BP neural network F1-Measure

Horizontal-Based Orchestration for Multi-Domain SFC in SDN/NFV-Enabled Satellite/Terrestrial Networks

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China Communications 2018年第5期15卷 77-91页

作者： Guanglei Li huachun zhou Bohao Feng Guanwen Li Qi Xu School of Electronic and Information Engineering Beijing Jiaotong University

It's promising to use Software-Defined Networking(SDN) and Network Functions Virtualization(NFV) to integrate satellite and terrestrial networks. To construct network service function chains in such a multi-domain environment, we propose a horizontal-based Multi-domain Service Function Chaining(Md-SFC) orchestration framework. In this framework, multi-domain orchestrators can coordinate with each other to guarantee the end-to-end service quality. Intra-domain orchestrators also coordinate SDN controllers and NFV management components to implement intra-domain service function chains. Based on this, we further propose a heuristic SFC mapping algorithm with a cooperative inter-domain path calculation method to map service function chains to infrastructures. In this method, master multi-domain orchestrator and intra-domain orchestrators coordinate to select proper inter-domain links. We compare the cooperative method with a naive uncooperative way that domains' topology information is provided to the master multi-domain orchestrator and it calculates the shortest inter-domain path between intra-domain service function chains directly. Simulation results demonstrate that our solution is feasible. It is able to construct end-to-end performance guaranteed service function chain by horizontal-based cooperation. The cooperative inter-domain path calculation method decreasesthe mapping load for the master orchestrator and gets the same end-to-end performance.

关键词：网络函数组织框架构造水 SFC 网络服务路径计算功能链端对端

Service Function Chain in Small Satellite-Based Software Defined Satellite Networks

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China Communications 2018年第3期15卷 157-167页

作者： Taixin Li huachun zhou Hongbin Luo Qi Xu Si Hua Bohao Feng Beijing Jiaotong University Beijing 100044 China Beihang University Beijing 100191 China

Software Defined Satellite Networks(SDSN) are proposed to solve the problems in traditional satellite networks, such as time-consuming configuration and inflexible traffic scheduling. The emerging application of small satellite and research of SDSN make it possible for satellite networks to provide flexible network services. Service Function Chain(SFC) can satisfy this need. In this paper, we are motivated to investigate applying SFC in the small satellite-based SDSN for service delivery. We introduce the structure of the multi-layer constellation-based SDSN. Then, we describe two deployment patterns of SFC in SDSN, the Multi-Domain(MD) pattern and the Satellite Formation(SF) pattern. We propose two algorithms, SFP-MD, and SFP-SF, to calculate the Service Function Path(SFP). We implement the algorithms and conduct contrast experiments in our prototype. Finally, we summarize the applicable conditions of two deployment patterns according to the experimental results in terms of hops, delay, and packet loss rate.

关键词：卫星网络网络服务软件定义函数链应用程序服务功能对比实验损失评价

Distributed Contact Plan Design for Multi-Layer Satellite-Terrestrial Network

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China Communications 2018年第1期15卷 23-34页

作者： Wenfeng Shi Deyun Gao huachun zhou Bohao Feng Haifeng Li Guanwen Li Wei Quan School of Electronic and Information Engineering Beijing Jiaotong University

In multi-layer satellite-terrestrial network, Contact Graph Routing(CGR) uses the contact information among satellites to compute routes. However, due to the resource constraints in satellites, it is extravagant to configure lots of the potential contacts into contact plans. What's more, a huge contact plan makes the computing more complex, which further increases computing time. As a result, how to design an efficient contact plan becomes crucial for multi-layer satellite network, which usually has a large scaled topology. In this paper, we propose a distributed contact plan design scheme for multi-layer satellite network by dividing a large contact plan into several partial parts. Meanwhile, a duration based inter-layer contact selection algorithm is proposed to handle contacts disruption problem. The performance of the proposed design was evaluated on our Identifier/Locator split based satellite-terrestrial network testbed with 79 simulation nodes. Experiments showed that the proposed design is able to reduce the data delivery delay.

关键词： contact graph routing distributedcontact plan multi-layered satellite network inter-layer contact selection

不同马铃薯品种(系)耐旱性综合评价及其指标筛选

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生态学杂志 2024年第1期43卷 178-187页

作者：邢媛李凯峰周进华郭华春李俊云南农业大学农学与生物技术学院昆明650201

以4个马铃薯品种(系)为供试材料,采用盆栽人工控水和组培条件下PEG-6000胁迫两种不同的模拟干旱形式进行处理,通过形态与生理指标综合评价其耐旱性差异,为马铃薯抗逆栽培及耐旱品种的选育提供依据。盆栽苗设置正常灌水(CK)和2个干旱胁... 详细信息

以4个马铃薯品种(系)为供试材料,采用盆栽人工控水和组培条件下PEG-6000胁迫两种不同的模拟干旱形式进行处理,通过形态与生理指标综合评价其耐旱性差异,为马铃薯抗逆栽培及耐旱品种的选育提供依据。盆栽苗设置正常灌水(CK)和2个干旱胁迫处理:中度干旱(T1,土壤相对湿度指数45%±5%)、轻度干旱(T2,土壤相对湿度55%±5%),组培试管苗设置4个PEG-6000浓度(5%、10%、15%和20%),对干旱胁迫下盆栽马铃薯的单株平均产量、9个形态指标、6个生理指标进行测定,使用3种方法对实验数据进行分析,评价了供试材料的耐旱性强弱并以组培苗进行验证。结果表明:经两种不同的模拟干旱处理后,筛选出的耐旱种质较为一致,耐旱性较好的品种(系)均为高代品系D1520和“滇薯97”,对干旱敏感的品种均为“青薯9号”和“滇薯1418”;从15个指标中简化出脱落酸含量、过氧化物酶活性、叶片数、株高、节数、分支数和叶片夹角7个对干旱胁迫敏感指标;各品种(系)的叶片数指标经组培试验验证后,可作为耐旱评价的重要指标。

关键词：马铃薯干旱胁迫组培苗 PEG-6000 主成分分析隶属函数

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磁力轴承——过去、现在和未来

轴承 2024年第7期 1-13页

作者：吴华春龙志强周瑾孙凤武汉理工大学机电工程学院武汉430070 国防科技大学智能科学学院长沙410073 南京航空航天大学机电学院南京210016 沈阳工业大学机械工程学院沈阳110870

磁力轴承是集电磁学、转子动力学、传感技术、控制工程等学科知识为一体的典型机电一体化产品,在高速、洁净、低功耗、低振动等应用场景具有机械轴承无法比拟的优势,但同样存在诸多技术难点。基于磁力轴承的发展历程,重点对磁力轴承的... 详细信息

磁力轴承是集电磁学、转子动力学、传感技术、控制工程等学科知识为一体的典型机电一体化产品,在高速、洁净、低功耗、低振动等应用场景具有机械轴承无法比拟的优势,但同样存在诸多技术难点。基于磁力轴承的发展历程,重点对磁力轴承的类型、工作原理、控制算法、控制硬件进行了综述和分析;介绍了磁力轴承功率放大器技术、控制技术、监测技术,以及设计、制造、系统集成等方面的关键技术;对磁力轴承目前在高速电动机、透平机械、人工心脏、储能飞轮、磁悬浮推进器、磁悬浮高速电主轴等方面的应用情况进行了梳理;提出了磁力轴承承载力、精度及可靠性、跌落保护、环境适应性、标准化、成本等面临的问题,并预测了磁力轴承的未来发展趋势。

关键词：滑动轴承磁力轴承控制算法控制器承载力人工心脏飞轮

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