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BC-BLPM:A Multi-Level Security Access Control Model Based on Blockchain Technology 被引量:4
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作者 Xiang Yu Zhangxiang Shu +1 位作者 Qiang Li Jun Huang 《China Communications》 SCIE CSCD 2021年第2期110-135,共26页
Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchai... Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchain is widely used in the field of access control with its decentralization,traceability and non-defective modification.Combining the blockchain technology and the Bell-LaPadula model,we propose a new access control model,named BCBLPM,for MLS environment.The“multi-chain”blockchain architecture is used for dividing resources into isolated access domains,providing a fine-grained data protection mechanism.The access control policies are implemented by smart contracts deployed in each access domain,so that the side chains of different access domains storage access records from outside and maintain the integrity of the records.Finally,we implement the BC-BLPM prototype system using the Hyperledger Fabric.The experimental and analytical results show that the model can adapt well to the needs of multi-level security environment,and it has the feasibility of application in actual scenarios. 展开更多
关键词 multi-level security(MLS) access control blockchain multi-chain smart contract
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Secure transmission in backhaul NOMA systems:A physical layer security design with untrusted user and eavesdropper
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作者 Chi-Bao Le Dinh-Thuan Do Miroslav Voznak 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1001-1013,共13页
In order to improve the Physical Layer Security(PLS)perspective,this paper aims to empower function of PLS by considering a backhaul Non-Orthogonal Multiple Access(NOMA)system in two practical situations.In the propos... In order to improve the Physical Layer Security(PLS)perspective,this paper aims to empower function of PLS by considering a backhaul Non-Orthogonal Multiple Access(NOMA)system in two practical situations.In the proposed schemes,the untrusted user intercepts information transmitted to the far user,or the external eavesdropper overhears confidential information sent to the far user in the context of NOMA technique.Unlike the conventional NOMA systems,this paper emphasizes the actual situations of the existence of actual illegal users and legitimate users,especially the reasonable use of relay selection architecture to improve the confidentiality performance.To evaluate the security properties of the proposed scheme,a comprehensive analysis of the Security Outage Probability(SOP)performance is first performed,and then the corresponding SOP asymptotic expressions are derived for real scenarios related to eavesdroppers and untrusted users.Numerical results are performed to verify the analysis in terms of the secure performance metric. 展开更多
关键词 Non-orthogonal multiple access(NOMA) Wireless backhaul secure outage probability Power allocation
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A Mandatory Access Control Framework in Virtual Machine System with Respect to Multi-level Security Ⅱ:Implementation 被引量:5
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作者 刘谦 王观海 +2 位作者 翁楚良 骆源 李明禄 《China Communications》 SCIE CSCD 2011年第2期86-94,共9页
This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level securi... This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level security(MLS) in Xen. The Virt-BLP model is the theoretical basis of this MAC framework,and this MAC framework is the implementation of Virt-BLP model. Our last paper focuses on Virt-BLP model,while this paper concentrates on the design and implementation of MAC framework. For there is no MAC framework applicable to MLS in virtual machine system at present,our MAC framework fills the blank by applying Virt-BLP model to Xen,which is better than current researches to guarantee the security of communication between virtual machines(VMs) . The experimental results show that our MAC framework is effective to manage the communication between VMs. 展开更多
关键词 virt-BLP model MAC framework multi-level security XEN
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A Mandatory Access Control Framework in Virtual Machine System with Respect to Multi-level Security I: Theory 被引量:1
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作者 LIU Qian WANG Guanhai WENG Chuliang LUO Yuan LI Minglu 《China Communications》 SCIE CSCD 2010年第4期137-143,共7页
At present,there are few security models which control the communication between virtual machines (VMs).Moreover,these models are not applicable to multi-level security (MLS).In order to implement mandatory access con... At present,there are few security models which control the communication between virtual machines (VMs).Moreover,these models are not applicable to multi-level security (MLS).In order to implement mandatory access control (MAC) and MLS in virtual machine system,this paper designs Virt-BLP model,which is based on BLP model.For the distinction between virtual machine system and non-virtualized system,we build elements and security axioms of Virt-BLP model by modifying those of BLP.Moreover,comparing with BLP,the number of state transition rules of Virt-BLP is reduced accordingly and some rules can only be enforced by trusted subject.As a result,Virt-BLP model supports MAC and partial discretionary access control (DAC),well satisfying the requirement of MLS in virtual machine system.As space is limited,the implementation of our MAC framework will be shown in a continuation. 展开更多
关键词 Virtual Machine System Mandatory access Control multi-level security Virt-BLP
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Service Security Architecture and Access Control Model for Cloud Computing 被引量:3
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作者 闫丹凤 杨放春 Tet Yeap 《China Communications》 SCIE CSCD 2011年第6期44-50,共7页
Security is a key problem for the development of Cloud Computing. A common service security architecture is a basic abstract to support security research work. The authorization ability in the service security faces m... Security is a key problem for the development of Cloud Computing. A common service security architecture is a basic abstract to support security research work. The authorization ability in the service security faces more complex and variable users and environment. Based on the multidimensional views, the service security architecture is described on three dimensions of service security requirement integrating security attributes and service layers. An attribute-based dynamic access control model is presented to detail the relationships among subjects, objects, roles, attributes, context and extra factors further. The model uses dynamic control policies to support the multiple roles and flexible authority. At last, access control and policies execution mechanism were studied as the implementation suggestion. 展开更多
关键词 cloud computing service security security architecture access control AUTHORIZATION
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A Lightweight ABE Security Protection Scheme in Cloud Environment Based on Attribute Weight
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作者 Lihong Guo Jie Yang Haitao Wu 《Computers, Materials & Continua》 SCIE EI 2023年第8期1929-1946,共18页
Attribute-based encryption(ABE)is a technique used to encrypt data,it has the flexibility of access control,high security,and resistance to collusion attacks,and especially it is used in cloud security protection.Howe... Attribute-based encryption(ABE)is a technique used to encrypt data,it has the flexibility of access control,high security,and resistance to collusion attacks,and especially it is used in cloud security protection.However,a large number of bilinear mappings are used in ABE,and the calculation of bilinear pairing is time-consuming.So there is the problem of low efficiency.On the other hand,the decryption key is not uniquely associated with personal identification information,if the decryption key is maliciously sold,ABE is unable to achieve accountability for the user.In practical applications,shared message requires hierarchical sharing in most cases,in this paper,we present a message security hierarchy ABE scheme for this scenario.Firstly,attributes were grouped and weighted according to the importance of attributes,and then an access structure based on a threshold tree was constructed according to attribute weight.This method saved the computing time for decryption while ensuring security and on-demand access to information for users.In addition,with the help of computing power in the cloud,two-step decryption was used to complete the access,which relieved the computing and storage burden on the client side.Finally,we simulated and tested the scheme based on CP-ABE,and selected different security levels to test its performance.The security proof and the experimental simulation result showthat the proposed scheme has high efficiency and good performance,and the solution implements hierarchical access to the shared message. 展开更多
关键词 Attribute-based encryption cloud security message hierarchy attribute weight access control
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Security and Privacy Frameworks for Access Control Big Data Systems 被引量:2
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作者 Paolina Centonze 《Computers, Materials & Continua》 SCIE EI 2019年第5期361-374,共14页
In the security and privacy fields,Access Control(AC)systems are viewed as the fundamental aspects of networking security mechanisms.Enforcing AC becomes even more challenging when researchers and data analysts have t... In the security and privacy fields,Access Control(AC)systems are viewed as the fundamental aspects of networking security mechanisms.Enforcing AC becomes even more challenging when researchers and data analysts have to analyze complex and distributed Big Data(BD)processing cluster frameworks,which are adopted to manage yottabyte of unstructured sensitive data.For instance,Big Data systems’privacy and security restrictions are most likely to failure due to the malformed AC policy configurations.Furthermore,BD systems were initially developed toped to take care of some of the DB issues to address BD challenges and many of these dealt with the“three Vs”(Velocity,Volume,and Variety)attributes,without planning security consideration,which are considered to be patch work.Some of the BD“three Vs”characteristics,such as distributed computing,fragment,redundant data and node-to node communication,each with its own security challenges,complicate even more the applicability of AC in BD.This paper gives an overview of the latest security and privacy challenges in BD AC systems.Furthermore,it analyzes and compares some of the latest AC research frameworks to reduce privacy and security issues in distributed BD systems,which very few enforce AC in a cost-effective and in a timely manner.Moreover,this work discusses some of the future research methodologies and improvements for BD AC systems.This study is valuable asset for Artificial Intelligence(AI)researchers,DB developers and DB analysts who need the latest AC security and privacy research perspective before using and/or improving a current BD AC framework. 展开更多
关键词 Big data access control distributed systems security PRIVACY
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Security analysis of access control model in hybrid cloud based on security entropy 被引量:2
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作者 车天伟 Ma Jianfeng +1 位作者 Li Na Wang Chao 《High Technology Letters》 EI CAS 2015年第2期200-204,共5页
To resolve the problem of quantitative analysis in hybrid cloud,a quantitative analysis method,which is based on the security entropy,is proposed.Firstly,according to the information theory,the security entropy is put... To resolve the problem of quantitative analysis in hybrid cloud,a quantitative analysis method,which is based on the security entropy,is proposed.Firstly,according to the information theory,the security entropy is put forward to calculate the uncertainty of the system' s determinations on the irregular access behaviors.Secondly,based on the security entropy,security theorems of hybrid cloud are defined.Finally,typical access control models are analyzed by the method,the method's practicability is validated,and security and applicability of these models are compared.Simulation results prove that the proposed method is suitable for the security quantitative analysis of the access control model and evaluation to access control capability in hybrid cloud. 展开更多
关键词 hybrid cloud security entropy classificatory access control model directly unauthorized access right about access indirectly unauthorized access
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Research on Physical Layer Security in Cognitive Wireless Networks with Multiple Eavesdroppers Based on Resource Allocation Algorithm
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作者 Yuxin Du Xiaoli He Yongming Huang 《Journal of Computer and Communications》 2023年第3期32-46,共15页
With the rapid development of the Internet of Things (IoT), non-Orthogonal Multiple Access (NOMA) technology and cognitive wireless network are two promising technologies to improve the spectral efficiency of the syst... With the rapid development of the Internet of Things (IoT), non-Orthogonal Multiple Access (NOMA) technology and cognitive wireless network are two promising technologies to improve the spectral efficiency of the system, which have been widely concerned in the field of wireless communication. However, due to the importance of ownership and privacy protection, the IoT system must provide corresponding security mechanisms. From the perspective of improving the transmission security of CR-NOMA system based on cognitive wireless network, and considering the shortcomings of traditional relay cooperative NOMA system, this paper mainly analyzes the eavesdropping channel model of multi-user CR-NOMA system and derives the expressions of system security and rate to improve the security performance of CR-NOMA system. The basic idea of DC planning algorithm and the scheme of sub-carrier power allocation to improve the transmission security of the system were introduced. An algorithm for DC-CR-NOMA was proposed to maximize the SSR of the system and minimize the energy loss. The simulation results show that under the same complexity, the security and speed of the system can be greatly improved compared with the traditional scheme. 展开更多
关键词 Cognitive Radio Networks Non-Orthogonal Multiple access Physical Layer security Sum of Safety Rates
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Remote Access Communications Security: Analysis of User Authentication Roles in Organizations 被引量:2
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作者 Ezer Osei Yeboah-Boateng Grace Dzifa Kwabena-Adade 《Journal of Information Security》 2020年第3期161-175,共15页
Remote access is a means of accessing resources outside one’s immediate physical location. This has made employee mobility more effective and productive for most organizations. Remote access can be achieved via vario... Remote access is a means of accessing resources outside one’s immediate physical location. This has made employee mobility more effective and productive for most organizations. Remote access can be achieved via various channels of remote communication, the most common being Virtual Private Networks (VPNs). The demand for remote access is on the rise, especially during the Covid-19 pandemic, and will continue to increase as most organizations are re-structuring to make telecommuting a permanent part of their mode of operation. Employee mobility, while presenting organizations with some advantages, comes with the associated risk of exposing corporate cyber assets to attackers. The remote user and the remote connectivity technology present some vulnerabilities which can be exploited by any threat agent to violate the confidentiality, integrity and availability (CIA) dimensions of these cyber assets. So, how are users and remote devices authenticated? To what extent is the established connection secured? With employee mobility on the rise, it is necessary to analyze the user authentication role since the mobile employee is not under the monitoring radar of the organization, and the environment from which the mobile employee connects may be vulnerable. In this study, an experiment was setup to ascertain the user authentication roles. The experiment showed the process of 2FA in user authentication and it proved to be an effective means of improving user authentication during remote access. This was depicted via the use of what the user has (mobile phone/soft-token) as a second factor in addition to what the user knows, i.e. password. This authentication method overcomes the security weaknesses inherent in single-factor user authentication via the use of password only. However, the results also showed that though 2FA user authentication ensures security, the remote devices could exhibit further vulnerabilities and pose serious risks to the organization. Thus, a varied implementation was recommended to further enhance the security of remote access communication with regards to the remote user authentication. 展开更多
关键词 Remote access Communications security User Authentication 2FA Virtual Private Network (VPN) TELECOMMUTING Threats VULNERABILITIES
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Ensuring Security, Confidentiality and Fine-Grained Data Access Control of Cloud Data Storage Implementation Environment 被引量:1
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作者 Amir Mohamed Talib 《Journal of Information Security》 2015年第2期118-130,共13页
With the development of cloud computing, the mutual understandability among distributed data access control has become an important issue in the security field of cloud computing. To ensure security, confidentiality a... With the development of cloud computing, the mutual understandability among distributed data access control has become an important issue in the security field of cloud computing. To ensure security, confidentiality and fine-grained data access control of Cloud Data Storage (CDS) environment, we proposed Multi-Agent System (MAS) architecture. This architecture consists of two agents: Cloud Service Provider Agent (CSPA) and Cloud Data Confidentiality Agent (CDConA). CSPA provides a graphical interface to the cloud user that facilitates the access to the services offered by the system. CDConA provides each cloud user by definition and enforcement expressive and flexible access structure as a logic formula over cloud data file attributes. This new access control is named as Formula-Based Cloud Data Access Control (FCDAC). Our proposed FCDAC based on MAS architecture consists of four layers: interface layer, existing access control layer, proposed FCDAC layer and CDS layer as well as four types of entities of Cloud Service Provider (CSP), cloud users, knowledge base and confidentiality policy roles. FCDAC, it’s an access policy determined by our MAS architecture, not by the CSPs. A prototype of our proposed FCDAC scheme is implemented using the Java Agent Development Framework Security (JADE-S). Our results in the practical scenario defined formally in this paper, show the Round Trip Time (RTT) for an agent to travel in our system and measured by the times required for an agent to travel around different number of cloud users before and after implementing FCDAC. 展开更多
关键词 CLOUD Computing CLOUD DATA STORAGE CLOUD Service PROVIDER Formula-Based CLOUD DATA access Control Multi-Agent System and secure Java Agent Development Framework
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IoT-Enabled Plant Monitoring System with Power Optimization and Secure Authentication
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作者 Samsul Huda Yasuyuki Nogami +5 位作者 Maya Rahayu Takuma Akada MdBiplob Hossain Muhammad Bisri Musthafa Yang Jie Le Hoang Anh 《Computers, Materials & Continua》 SCIE EI 2024年第11期3165-3187,共23页
Global food security is a pressing issue that affects the stability and well-being of communities worldwide.While existing Internet of Things(IoT)enabled plant monitoring systems have made significant strides in agric... Global food security is a pressing issue that affects the stability and well-being of communities worldwide.While existing Internet of Things(IoT)enabled plant monitoring systems have made significant strides in agricultural monitoring,they often face limitations such as high power consumption,restricted mobility,complex deployment requirements,and inadequate security measures for data access.This paper introduces an enhanced IoT application for agricultural monitoring systems that address these critical shortcomings.Our system strategically combines power efficiency,portability,and secure access capabilities,assisting farmers in monitoring and tracking crop environmental conditions.The proposed system includes a remote camera that captures images of surrounding plants and a sensor module that regularly monitors various environmental factors,including temperature,humidity,and soil moisture.We implement power management strategies to minimize energy consumption compared to existing solutions.Unlike conventional systems,our implementation utilizes the Amazon Web Services(AWS)cloud platform for reliable data storage and processing while incorporating comprehensive security measures,including Two-Factor Authentication(2FA)and JSON Web Tokens(JWT),features often overlooked in current agricultural IoT solutions.Users can access this secure monitoring system via a developed Android application,providing convenient mobile access to the gathered plant data.We validate our system’s advantages by implementing it with two potted garlic plants on Okayama University’s rooftop.Our evaluation demonstrates high sensor reliabil-ity,with strong correlations between sensor readings and reference data,achieving determination coefficients(R2)of 0.979 for temperature and 0.750 for humidity measurements.The implemented power management strategies extend battery life to 10 days on a single charge,significantly outperforming existing systems that typically require daily recharging.Furthermore,our dual-layer security implementation utilizing 2FA and JWT successfully protects sensitive agricultural data from unauthorized access. 展开更多
关键词 Plant monitoring AGRICULTURE food security environmental monitoring IOT power management AWS secure access JWT
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Big Data Access Control Mechanism Based on Two-Layer Permission Decision Structure
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作者 Aodi Liu Na Wang +3 位作者 Xuehui Du Dibin Shan Xiangyu Wu Wenjuan Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1705-1726,共22页
Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policy... Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policymanagement efficiency and difficulty in accurately describing the access control policy. To overcome theseproblems, this paper proposes a big data access control mechanism based on a two-layer permission decisionstructure. This mechanism extends the attribute-based access control (ABAC) model. Business attributes areintroduced in the ABAC model as business constraints between entities. The proposed mechanism implementsa two-layer permission decision structure composed of the inherent attributes of access control entities and thebusiness attributes, which constitute the general permission decision algorithm based on logical calculation andthe business permission decision algorithm based on a bi-directional long short-term memory (BiLSTM) neuralnetwork, respectively. The general permission decision algorithm is used to implement accurate policy decisions,while the business permission decision algorithm implements fuzzy decisions based on the business constraints.The BiLSTM neural network is used to calculate the similarity of the business attributes to realize intelligent,adaptive, and efficient access control permission decisions. Through the two-layer permission decision structure,the complex and diverse big data access control management requirements can be satisfied by considering thesecurity and availability of resources. Experimental results show that the proposed mechanism is effective andreliable. In summary, it can efficiently support the secure sharing of big data resources. 展开更多
关键词 Big data access control data security BiLSTM
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Adaptable and Dynamic Access Control Decision-Enforcement Approach Based on Multilayer Hybrid Deep Learning Techniques in BYOD Environment
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作者 Aljuaid Turkea Ayedh M Ainuddin Wahid Abdul Wahab Mohd Yamani Idna Idris 《Computers, Materials & Continua》 SCIE EI 2024年第9期4663-4686,共24页
Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control sy... Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control systems,such as Attribute-Based Access Control(ABAC)and Role-Based Access Control(RBAC),are limited in their ability to enforce access decisions due to the variability and dynamism of attributes related to users and resources.This paper proposes a method for enforcing access decisions that is adaptable and dynamic,based on multilayer hybrid deep learning techniques,particularly the Tabular Deep Neural Network Tabular DNN method.This technique transforms all input attributes in an access request into a binary classification(allow or deny)using multiple layers,ensuring accurate and efficient access decision-making.The proposed solution was evaluated using the Kaggle Amazon access control policy dataset and demonstrated its effectiveness by achieving a 94%accuracy rate.Additionally,the proposed solution enhances the implementation of access decisions based on a variety of resource and user attributes while ensuring privacy through indirect communication with the Policy Administration Point(PAP).This solution significantly improves the flexibility of access control systems,making themmore dynamic and adaptable to the evolving needs ofmodern organizations.Furthermore,it offers a scalable approach to manage the complexities associated with the BYOD environment,providing a robust framework for secure and efficient access management. 展开更多
关键词 BYOD security access control access control decision-enforcement deep learning neural network techniques TabularDNN MULTILAYER dynamic adaptable FLEXIBILITY bottlenecks performance policy conflict
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Hadoop Distributed File System Security Challenges and Examination of Unauthorized Access Issue 被引量:1
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作者 Wahid Rajeh 《Journal of Information Security》 2022年第2期23-42,共20页
Hadoop technology is followed by some security issues. At its beginnings, developers paid attention to the development of basic functionalities mostly, and proposal of security components was not of prime interest. Be... Hadoop technology is followed by some security issues. At its beginnings, developers paid attention to the development of basic functionalities mostly, and proposal of security components was not of prime interest. Because of that, the technology remained vulnerable to malicious activities of unauthorized users whose purpose is to endanger system functionalities or to compromise private user data. Researchers and developers are continuously trying to solve these issues by upgrading Hadoop’s security mechanisms and preventing undesirable malicious activities. In this paper, the most common HDFS security problems and a review of unauthorized access issues are presented. First, Hadoop mechanism and its main components are described as the introduction part of the leading research problem. Then, HDFS architecture is given, and all including components and functionalities are introduced. Further, all possible types of users are listed with an accent on unauthorized users, which are of great importance for the paper. One part of the research is dedicated to the consideration of Hadoop security levels, environment and user assessments. The review also includes an explanation of Log Monitoring and Audit features, and detail consideration of authorization and authentication issues. Possible consequences of unauthorized access to a system are covered, and a few recommendations for solving problems of unauthorized access are offered. Honeypot nodes, security mechanisms for collecting valuable information about malicious parties, are presented in the last part of the paper. Finally, the idea for developing a new type of Intrusion Detector, which will be based on using an artificial neural network, is presented. The detector will be an integral part of a new kind of virtual honeypot mechanism and represents the initial base for future scientific work of authors. 展开更多
关键词 Hadoop security Issue Unauthorized access Honeypot Node Intrusion Detector
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A Method of Auxiliary Planning for Intelligent Substation Access System Based on Security Region
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作者 Gao Yi Songtao Zhang +4 位作者 Chao Qin Yuan Zeng Yang Yang Yingying Liu Shengwei Li 《Energy and Power Engineering》 2017年第4期675-682,共8页
This paper presents an auxiliary planning method for intelligent substation access system based on security region. Firstly, the method of resolving the static voltage security region is proposed. Secondly, the method... This paper presents an auxiliary planning method for intelligent substation access system based on security region. Firstly, the method of resolving the static voltage security region is proposed. Secondly, the method of constructing the optimal index of substation accession is given, which is used to describe the priority of the node into the substation. Finally, a complete set of intelligent substation access system auxiliary planning strategy is given, which takes into account the constraints of the normal operation of the grid on the voltage amplitude. 展开更多
关键词 SUBSTATION the STATIC security REGION Optimized Index of SUBSTATION accessION
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Food Access and Experience of Food Insecurity in Nigerian Households during the COVID-19 Lockdown
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作者 Folake O. Samuel Toluwalope E. Eyinla +3 位作者 Ariyo Oluwaseun Oluwatosin O. Leshi Bartholomew I. C. Brai Wasiu A. O. Afolabi 《Food and Nutrition Sciences》 2021年第11期1062-1072,共11页
The food insecurity experiences and related behaviors of Nigerian households during the COVID-19 lockdown have not been fully discussed. This study was conducted to elicit information on the impact of COVID-19 lockdow... The food insecurity experiences and related behaviors of Nigerian households during the COVID-19 lockdown have not been fully discussed. This study was conducted to elicit information on the impact of COVID-19 lockdown on economic and behavioral patterns related to food access. An online-based semi-structured questionnaire distributed through messaging platforms was used to collect information on characteristics, food purchasing behaviour be<span>fore and during COVID-19 lockdown among respondents. Experience of</span> food insecurity was assessed using Food Insecurity Experience Scale (FIES). A total of 883 responses were received and analyzed using SPSS Version 20.0. Most of the respondents (90.5%) were at home or had stopped going to work due to COVID-19 restrictions. Even though smaller households had higher food <span>expenditure claims than larger households (p = 0.012), the larger the</span> house<span>hold, the more acute the challenge of economic access to food (p = 0.050)</span>. Location (p = 0.000), age (p = 0.003), occupation (p = 0.014) and income level (p = 0.000) were associated with experience of food insecurity. In conclusion, lockdown restrictions increased food expenditure and experience of food insecurity among the respondents and thus we recommend the probe of long-term consequences of deviations from usual food access on undernutrition or overnutrition in Nigerian households. 展开更多
关键词 Food security COVID-19 FIES Lockdown Food access
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Security of Broadband Access Network
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作者 Wang Deqiang(Network Division of ZTE Corporation, Shanghai 201203, China) 《ZTE Communications》 2007年第1期37-41,共5页
Due to the rapid development of broadband access technologies, the broadband access networks have wider and wider application. However, with the development, the security issue became a public concern. Under the envir... Due to the rapid development of broadband access technologies, the broadband access networks have wider and wider application. However, with the development, the security issue became a public concern. Under the environment of access network, customers, access equipment and networks all face various threats, especially those from the user side. Such technologies and solutions as port positioning, fraud prevention on Medium Access Control (MAC) addresses and monitoring of illegal services might be the solution to the security problem existing in the current networks. 展开更多
关键词 access MAC security of Broadband access Network PPPOE
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The Design of an Intelligent Security Access Control System Based on Fingerprint Sensor FPC1011C
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作者 Yan Wang Hongli Liu Jun Feng 《Circuits and Systems》 2010年第1期30-33,共4页
This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC- 1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisition mod... This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC- 1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisition module and a wireless alarm module were designed by using the fingerprint sensor FPC1011C and GPRS module SIM100 respectively. The whole system was implemented wireless alarm through messages and GPRS-Internet in the GSM/GPRS web. In order to achieve the simple and high Real-time system, the μC-Linux system migration was also implemented. 展开更多
关键词 FINGERPRINT Sensor security access Control System ARM WIRELESS ALARM
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Intelligent Security Auditing Based on Access Control of Devices in Ad Hoc Network
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作者 徐光伟 史有群 +2 位作者 朱明 吴国文 曹奇英 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期50-52,共3页
Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy a... Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy and operating regulation and used to identify abnormal operation. Model of security auditing based on access control of devices will be advanced to register sign of devices and property of event of access control and to audit those actions. In the end, the model is analyzed and simulated. 展开更多
关键词 Ad Hoc security auditing access control of devices sign of devices property of event.
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