Security analysis of access control model in hybrid cloud based on security entropy

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.

The Research of Role Tree-Based Access Control Model

Towards the crossing and coupling permissions in tasks existed widely in many fields and considering the design of role view must rely on the activities of the tasks process,based on Role Based Accessing Control (RBAC) model,this paper put forward a Role Tree-Based Access Control (RTBAC) model. In addition,the model definition and its constraint formal description is also discussed in this paper. RTBAC model is able to realize the dynamic organizing,self-determination and convenience of the design of role view,and guarantee the least role permission when task separating in the mean time.

Tenant-based access control model for multi-tenancy and sub-tenancy architecture in Software-as-a-Service

Software-as-a-Service （SaaS） introduces multi- tenancy architecture （MTA）. Sub-tenancy architecture （STA）, is an extension of MTA, allows tenants to offer services for subtenant developers to customize their applications in the SaaS infrastructure. In a STA system, tenants can create sub- tenants, and grant their resources （including private services and data） to their subtenants. The isolation and sharing re- lations between parent-child tenants, sibling tenants or two non-related tenants are more complicated than those between tenants in MTA. It is important to keep service components or data private, and at the same time, allow them to be shared, and support application customizations for tenants. To ad- dress this problem, this paper provides a formal definition of a new tenant-based access control model based on administra- tive role-based access control （ARBAC） for MTA and STA in service-oriented SaaS （called TMS-ARBAC）. Autonomous areas （AA） and AA-tree are proposed to describe the auton- omy of tenants, including their isolation and sharing relation- ships. Authorization operations on AA and different resource sharing strategies are defined to create and deploy the access control scheme in STA models. TMS-ARBAC model is ap- plied to design a geographic e-Science platform.

Specification and Verification of a Topology-Aware Access Control Model for Cyber-Physical Space

The cyber-physical space is a spatial environment that integrates the cyber and physical worlds to provide an intelligent environment for users to conduct their day-to-day activities. Mobile users and mobile objects are ubiquitous in this space, thereby exerting tremendous pressure on its security model. This model must ensure that both cyber and physical objects are always handled securely in this dynamic environment. In this paper,we propose a systematic solution to be able to specify security policies of the cyber-physical space and ensure that security requirements hold in these policies. We first formulate a topology configuration model to capture the topology characteristics of the cyber and physical worlds. Then, based on this model, a Topology-Aware CyberPhysical Access Control model(TA-CPAC) is proposed, which can ensure the security of the cyber and physical worlds at the same time by adjusting permission assignment dynamically. Then, the topology configuration and TA-CPAC models are formalized by bigraphs and Bigraph Reactive System(BRS), respectively, allowing us to use model checking to rationalize the consequences of the evolution of topological configurations on the satisfaction of security requirements. Finally, a case study on a building automation access control system is conducted to evaluate the effectiveness of the proposed approach.

A Multi-Tenant Usage Access Model for Cloud Computing

Most cloud services are built with multi-tenancy which enables data and configuration segregation upon shared infrastructures.It offers tremendous advantages for enterprises and service providers.It is anticipated that this situation will evolve to foster cross-tenant collaboration supported by Authorization as a service.To realize access control in a multi-tenant cloud computing environment,this study proposes a multi-tenant cloud computing access control model based on the traditional usage access control model by building trust relations among tenants.The model consists of three sub-models,which achieve trust relationships between tenants with different granularities and satisfy the requirements of different application scenarios.With an established trust relation in MT-UCON(Multi-tenant Usage Access Control),the trustee can precisely authorize cross-tenant accesses to the trustor’s resources consistent with constraints over the trust relation and other components designated by the trustor.In addition,the security of the model is analyzed by an information flow method.The model adapts to the characteristics of a dynamic and open multi-tenant cloud computing environment and achieves fine-grained access control within and between tenants.

Virus spreading in wireless sensor networks with a medium access control mechanism

In this paper, an extended version of standard susceptible-infected （SI） model is proposed to consider the influence of a medium access control mechanism on virus spreading in wireless sensor networks. Theoretical analysis shows that the medium access control mechanism obviously reduces the density of infected nodes in the networks, which has been ignored in previous studies. It is also found that by increasing the network node density or node communication radius greatly increases the number of infected nodes. The theoretical results are confirmed by numerical simulations.

Experience-Based Access Control in UbiComp: A New Paradigm

Experience is a sociological concept and builds over time. In a broader sense, the human-centered equivalents of experience and trust apply to D2D interaction. Ubiquitous computing (UbiComp) embeds intelligence and computing capabilities in everyday objects to make them effectively communicate, share resources, and perform useful tasks. The safety of resources is a serious problem. As a result, authorization and access control in UbiComp is a significant challenge. Our work presents experience as an outcome of history (HI), reliability (RL), transitivity (TR), and Ubiquity (UB). This experience model is easily adaptable to a variety of self-regulating context-aware access control systems. This paper proposes a framework for Experience-Based Access Control (EX-BAC) with all major services provided by the model. EX-BAC extends attribute-based access control. It uses logical device type and experience as context parameters for policy design. When compared with the state-of-the-art, EX-BAC is efficient with respect to response time.

Mobility Conscious Medium Access Control Scheme for Wireless Sensor Networks: A Conceptual Approach

Mobility in Wireless Sensor Network (WSN) presents distinctive challenges in Medium Access Control (MAC) scheme. Numerous MAC protocols for sensor networks assume that sensor nodes are static and focus primarily on energy efficiency. This work seeks to develop an improved mobility conscious medium access control scheme for wireless sensor networks with a view to enhance energy conservation on mobile sensor nodes. On this note, mobility patterns of different scenarios are modelled using Gauss Markov Mobility Model (GMMM) to determine the position and distance of the sensor nodes and how they are correlated in time.

Study on Mandatory Access Control in a Secure Database Management System

This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation hierarchical data model is extended to multilevel relation hierarchical data model. Based on the multilevel relation hierarchical data model, the concept of upper lower layer relational integrity is presented after we analyze and eliminate the covert channels caused by the database integrity. Two SQL statements are extended to process polyinstantiation in the multilevel secure environment. The system is based on the multilevel relation hierarchical data model and is capable of integratively storing and manipulating multilevel complicated objects ( e.g., multilevel spatial data) and multilevel conventional data ( e.g., integer, real number and character string).

零信任的安全模型研究

零信任被认为是一种新的安全范式,从安全模型视角,揭示了零信任架构以“身份和数据”为主线的安全模型深化与整合.零信任以身份为核心建立全景管控实体链条,围绕实体属性功能生命周期等建立深度防御,并集中重定向实体间信息的流动,整合信息通道,实现层层防护和细粒度动态化访问控制,最后从攻击者视角在信息流通道关键节点设置主动防御机制.由于零信任系统一定会成为高价值资产,探讨了零信任系统演进中与业务深度融合、零信任自身安全和弹性服务能力的新趋势.通过对零信任蕴含安全模型和自身安全性的分析,期望能够为零信任在应用中的架构设计、技术演进、应用安全提供更加清晰的技术发展路径.

基于策略的动态角色分配模型及应用

访问控制是应用系统中的重要问题之一。传统的基于角色的访问控制(RBAC)方案需要预先定义和同步用户-角色赋值关系,这会带来管理成本和同步开销,并且限制了应用系统的灵活性和动态性。文章提出一种基于策略的动态角色分配模型(Policy-based Dynamic Role Assignment Model——PDRA),它无需同步用户就可以自定义角色,并通过策略匹配的方式实现动态分配。模型完全兼容RBAC,可以成为RBAC良好的扩展机制。文章给出了模型的定义和算法,评估了模型的性能,并在华东师范大学的数据治理平台中进行了应用,验证了该方案的可行性和有效性。

基于RBAC模型的前后端分离系统设计与实现

权限管理是现代信息管理系统核心功能之一,能够让用户可以安全访问系统数据,其中基于角色的访问控制模型是常用的一种权限管理模型,其优点是能够灵活地处理角色与权限之间的变化问题,为复杂的权限管理问题提供便利性。另一方面前后端分离技术能够很好地解决前端页面开发和后端服务器功能开发解耦的问题,让分工双方更加注重各自面对的业务问题,减少对开发人员技术门槛的要求,从而大大提高了开发效率。因此采用前后端分离技术实现通用的基于角色的访问控制系统具有一定的实用价值。

统一驱动与能力抽象结合的无人机载荷虚拟化方法及实现

随着无人机及其集群应用不断深入并日益广泛,无人机载荷呈现种类多样、形态异构、接口复杂等特点,但同时要求系统能快速接入并高效管理载荷。为了解耦无人机载荷与系统平台的紧密关系,扩展对异构载荷的兼容能力,提出一种新型的载荷设备虚拟化方法。提出分层驱动模型,实现载荷硬件设备和驱动软件的解耦,使载荷设备接入过程标准化,该模型通过软硬件协同实现;提出基于“能力”的载荷抽象,解耦载荷应用功能及其设备实体;给出了载荷虚拟化方法具体实现及其典型验证实例。上述载荷设备虚拟化方法通过载荷应用、载荷驱动及载荷设备的软硬件解耦,增强了系统接入不同载荷的兼容性及扩展性,提高了统一管理多种载荷的效率。

TA-BAC:基于有向无环图的访问控制模型

为解决传统访问控制模型存在有效期内策略获取困难、传输过程安全性低等问题,研究更细粒度、更具适用性的基于属性权能的访问控制模型(token attribute based access control, TA-BAC)。构建一种基于DAG区块链的TA-BAC访问控制模型;实现轻量化区块链存储,设计灵活的策略获取流程;引入基于属性的加密算法实现访问控制流程中凭证token的安全性增强机制。对优化后的访问控制模型进行分析验证,其结果表明,该模型具有较好的安全性和更高的性能,面对不同规模的访问控制场景具备良好的适用性。

基于并行网络通信的隐私风险自适应访问控制数学模型

当前隐私风险自适应访问控制机制一般设定为单向结构,访问控制的约束效率较低,导致平均风险逐渐上升,为此提出基于并行网络通信的隐私风险自适应访问控制数学模型。根据当前的测试需求及标准,进行隐私风险访问控制问题描述及风险值计算,协同设定多目标自适应访问控制请求机制。以此为基础,构建并行网络通信隐私风险访问控制结构,以风险追踪链处理的方法实现访问控制。最终得出的结论表明:经过选定的5个测试小组的对比,在相同的环境下,访问控制执行者和恶意者所测定出的平均风险值差异较大,访问控制执行者的平均风险值差明显低于恶意者的平均风险值差,说明在并行网络通信技术的辅助下,隐私风险的自适应控制模型的实际应用效果得到了提升。

基于演化博弈的大数据信息泄漏风险访问控制模型设计

大数据信息泄漏会导致网络主机所承担的运行风险增加,严重时下级网络终端会出现无法访问大数据信息服务器的情况;针对上述问题,设计了基于演化博弈的大数据信息泄漏风险访问控制模型;以演化博弈模型为基础,完成对大数据信息均衡点的演化处理,求解信息博弈概率,推导演化博弈模型表达式,从而完善基于演化博弈的大数据信息模糊化处理流程;计算大数据信息泄漏行为的信任度标准,参考信息监控器设置条件,实现对大数据信息泄漏风险的评估;针对风险评估结果,完成大数据信息的访问证据取样,计算访问控制阈值,实现对信息泄漏风险访问的控制,完成基于演化博弈的大数据信息泄漏风险访问控制模型的设计;实验结果表明,所提方法的大数据信息瞬时泄漏量始终小于2.3×10^(11)MB,网络主机所承担的运行风险得到有效控制,下级网络终端不会出现无法访问大数据信息服务器的情况。

Analysis and Application for Integrity Model on Trusted Platform

To build a trusted platform based on Trusted Computing Platform Alliance(TCPA)' s recommendation, we analyze the integrity mechanism for such a PC platfoim in this paper.By combinning access control model with information flow model, we put forwarda combinedprocess-based lattice model to enforce security This moelel creates a trust chain by which we canmanage a series of processes from a core root of trust module to some other application modules Inthe model, once the trust chain is created andmanaged cor-rectly, the integrity of the computer'shardware and sofware has bctn maintained, so does the confidentiality and authenticity. Moreover, arelevant implementation of the model is explained.

IPv6环境下校园网安全防护技术的研究与应用

为提高IPv6环境下校园网络的安全防护能力,文中针对IPv6网络协议的特点,设计了安全防护算法模型,以此来应对IPv6带来的网络安全挑战。通过网络入侵检测系统(NIDS)选择、IPv6地址分配安全机制、数据加密与验证技术、算法模型优化等技术手段来提升校园网络安全防护能力,验证了该算法模式的功能有效性。结果表明,该模型能提升IPv6环境下校园网的安全级别,降低安全威胁发生率,为校园网安全管理提供技术支持。

零信任技术在铁路信息网络安全场景的应用构想

铁路信息网络承载客运、货运、经营管理等核心系统,网络安全关乎国家关键信息基础设施安全和人民群众财产安全。铁路信息网络除需提供持续增强的计算、通信、存储支撑能力外,还应不断完善安全保障体系和防御手段。考虑大数据、云计算、人工智能等新兴技术规模化应用导致的访问方式多元化、网络边界泛化、基础环境复杂异构化、数据资产规模化等特点,基于铁路信息网络基础设施、应用系统和安全防护现状,结合零信任模型和关键技术,针对既有应用访问控制措施的补强思路,设计提出基于零信任的铁路网络访问架构,以期管控访问行为,收敛应用网络暴露面。

高比例光伏接入的分布式储能容量自适应协调控制方法

光伏发电具有一定的波动性和不确定性,天气、季节等因素会导致光伏功率的变化,需要储能系统实时跟踪、预测和调整以保持供需平衡,但波动性和不确定性增加了控制的复杂性。为此,提出一种新的分布式储能容量自适应协调控制方法。计算接入高比例光伏电能后储能无功损耗,设置功率约束条件,确保功率的稳定性。基于此,以电压条件最优、接入负荷和净功率最低、高比例光伏接入处的功率可调节范围最优为调控目标,实现高比例光伏接入的分布式储能容量自适应协调控制。实验数据证明,所提方法在控制效果方面具有显著优势,能够实现高效的分布式储能控制,并确保光伏的高效出力。