An Automated Semantic Negotiation for Cloud Service Level Agreements

Mostly, cloud agreements are signed between the consumer and the provider using online click-through agreements. Several issues and conflicts exist in the negotiation of cloud agreement terms due to the legal and ambiguous terms in Service Level Agreements (SLA). Semantic knowledge applied during the formation and negotiation of SLA can overcome these issues. Cloud SLA negotiation consists of numerous activities such as formation of SLA templates, publishing it in registry, verification and validation of SLA, monitoring for violation, logging and reporting and termination. Though these activities are interleaved with each other, semantic synchronization is still lacking. To overcome this, a novel SLA life cycle using semantic knowledge to automate the cloud negotiation has been formulated. Semantic web platform using ontologies is designed, developed and evaluated. The resultant platform increases the task efficiency of the consumer and the provider during negotiation. Precision and recall scores for Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS) SLAs were calculated. And it reveals that applying semantic knowledge helps the extraction of meaningful answers from the cloud actors.

Adaptive Runtime Monitoring of Service Level Agreement Violations in Cloud Computing

The cloud service level agreement(SLA)manage the relationship between service providers and consumers in cloud computing.SLA is an integral and critical part of modern era IT vendors and communication contracts.Due to low cost and flexibility more and more consumers delegate their tasks to cloud providers,the SLA emerges as a key aspect between the consumers and providers.Continuous monitoring of Quality of Service(QoS)attributes is required to implement SLAs because of the complex nature of cloud communication.Many other factors,such as user reliability,satisfaction,and penalty on violations are also taken into account.Currently,there is no such policy of cloud SLA monitoring to minimize SLA violations.In this work,we have proposed a cloud SLA monitoring policy by dividing a monitoring session into two parts,for critical and non-critical parameters.The critical and non-critical parameters will be decided on the interest of the consumer during SLA negotiation.This will help to shape a new comprehensive SLA based Proactive Resource Allocation Approach(RPAA)which will monitor SLA at runtime,analyze the SLA parameters and try to find the possibility of SLA violations.We also have implemented an adaptive system for allocating cloud IT resources based on SLA violations and detection.We have defined two main components of SLA-PRAA i.e.,(a)Handler and(b)Accounting and Billing Manager.We have also described the function of both components through algorithms.The experimental results validate the performance of our proposed method in comparison with state-of-the-art cloud SLA policies.

基于Web Services的SLA监测系统体系结构

为解决现有SLA监测系统存在的不足,提出了基于Web Services的SLA监测系统体系结构,描述了该体系结构中相关服务的功能和SLA监测流程。为规范化不同层次SLA参数的映射,提出了通用的SLA参数映射模型。原型系统的实现验证了该体系结构能够满足下一代互联网环境下的多业务的监测需求。

Auto-Scaling Framework for Enhancing the Quality of Service in the Mobile Cloud Environments

On-demand availability and resource elasticity features of Cloud computing have attracted the focus of various research domains.Mobile cloud computing is one of these domains where complex computation tasks are offloaded to the cloud resources to augment mobile devices’cognitive capacity.However,the flexible provisioning of cloud resources is hindered by uncertain offloading workloads and significant setup time of cloud virtual machines(VMs).Furthermore,any delays at the cloud end would further aggravate the miseries of real-time tasks.To resolve these issues,this paper proposes an auto-scaling framework(ACF)that strives to maintain the quality of service(QoS)for the end users as per the service level agreement(SLA)negotiated assurance level for service availability.In addition,it also provides an innovative solution for dealing with the VM startup overheads without truncating the running tasks.Unlike the waiting cost and service cost tradeoff-based systems or threshold-rule-based systems,it does not require strict tuning in the waiting costs or in the threshold rules for enhancing the QoS.We explored the design space of the ACF system with the CloudSim simulator.The extensive sets of experiments demonstrate the effectiveness of the ACF system in terms of good reduction in energy dissipation at the mobile devices and improvement in the QoS.At the same time,the proposed ACF system also reduces the monetary costs of the service providers.

Integrating Requirements with SLI Layer for Cloud Computing Services to Meet SLA and QoS

Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing information technology capabilities and requirements. Many technologies are being merged with cloud computing, same as that orchestrations can boost cloud service provisioning process. The usage of orchestrations can play vital role to provision cloud services. Cloud service providers can create scalable cloud services at low cost by organizing cloud infrastructure by using cloud orchestrations. Dynamic orchestration flows can generate required cloud computing services to meet service level agreements and quality of services. There is a need to understand issues and barriers involved to integrate cloud orchestrations with cloud service provisioning process. There is also need to understand business related problems bordering cloud computing technology. There is much capacity to do targeted research work for cloud orchestrations and its integration with service level agreements as well as with SLI (service level integration) layer. In this article we have elaborated detailed analysis and identified a number of issues that will affect the cloud service users as well as cloud service providers and cloud service provisioning system. We are defining an approach to orchestrate cloud infrastructure by using orchestration flows, to generate cloud services in order to meet service level agreements and quality of standard.

基于Web Services服务管理系统的研究

提出了基于Web Services的服务管理体系结构,并设计和实现了基于XML服务管理信息模型和基于SOAP服务管理协议。该系统能够对跨不同管理域的服务进行有效的管理和对服务管理系统进行灵活的配置。通过用XPath表达式指定范围和过滤规则,有效地共享跨不同管理域的服务管理信息,通过XPath表达式指定的过滤规则支持较细粒度的事件通知,解决了跨不同管理域间实现服务管理的难题。

Toward Cloud Computing QoS Architecture:Analysis of Cloud Systems and Cloud Services

Cloud can be defined as a new computing paradigm that provides scalable, on-demand, and virtualized resources for users. In this style of computing, users can access a shared pool of computing resources which are provisioned with minimal management efforts of users. Yet there are some obstacles and concerns about the use of clouds. Guaranteeing quality of service QoS by service providers can be regarded as one of the main concerns for companies tending to use it. Service provisioning in clouds is based on service level agreements representing a contract negotiated between users and providers. According to this contract, if a provider cannot satisfy its agreed application requirements, it should pay penalties as compensation. In this paper, we intend to carry out a comprehensive survey on the models proposed in literature with respect to the implementation principles to address the QoS guarantee issue. © 2014 Chinese Association of Automation.

Access Control Policy Analysis and Access Denial Method for Cloud Services

Personal cloud computing is an emerging trend in the computer industry. For a sustainable service, cloud computing services must control user access. The essential business characteristics of cloud computing are payment status and service level agreement. This work proposes a novel access control method for personal cloud service business. The proposed method sets metadata, policy analysis rules, and access denying rules. Metadata define the structure of access control policies and user requirements for cloud services. The policy analysis rules are used to compare conflicts and redundancies between access control policies. The access denying rules apply policies for inhibiting inappropriate access. The ontology is a theoretical foundation of this method. In this work, ontologies for payment status, access permission, service level, and the cloud provide semantic information needed to execute rules. A scenario of personal data backup cloud service is also provided in this work. This work potentially provides cloud service providers with a convenient method of controlling user access according to changeable business and marketing strategies.

Intelligent Model for Predicting the Quality of Services Violation

Cloud computing is providing IT services to its customer based on Service level agreements(SLAs).It is important for cloud service providers to provide reliable Quality of service(QoS)and to maintain SLAs accountability.Cloud service providers need to predict possible service violations before the emergence of an issue to perform remedial actions for it.Cloud users’major concerns;the factors for service reliability are based on response time,accessibility,availability,and speed.In this paper,we,therefore,experiment with the parallel mutant-Particle swarm optimization(PSO)for the detection and predictions of QoS violations in terms of response time,speed,accessibility,and availability.This paper also compares Simple-PSO and Parallel MutantPSO.In simulation results,it is observed that the proposed Parallel MutantPSO solution for cloud QoS violation prediction achieves 94%accuracy which is many accurate results and is computationally the fastest technique in comparison of conventional PSO technique.

SYSTEM RELIABILITY OF ASSURED ACCURACY RATE FOR MULTI-STATE COMPUTER NETWORKS FROM SERVICE LEVEL AGREEMENTS VIEWPOINT

From the viewpoint of service level agreements, the transmission accuracy rate is one of critical performance indicators to assess internet quality for system managers and customers. Under the assumption that each arc＇s capacity is deterministic, the quickest path problem is to find a path sending a specific of data such that the transmission time is minimized. However, in many real-life networks such as computer networks, each arc has stochastic capacity, lead time and accuracy rate. Such a network is named a multi-state computer network. Under both assured accuracy rate and time constraints, we extend the quickest path problem to compute the probability that d units of data can be sent through multiple minimal paths simultaneously. Such a probability named system reliability is a performance indicator to provide to managers for understanding the ability of system and improvement. An efficient algorithm is proposed to evaluate the system reliability in terms of the approach of minimal paths.

基于SLA与用户评价的云计算信任模型

针对用户对云服务提供商缺乏信任的问题,提出一个基于服务等级协议(SLA)与用户评价的云计算信任模型。通过分析云服务提供商的SLA确认其承诺的服务质量,根据用户的评价确定云服务提供商对SLA的履行情况,综合两方面内容计算云服务的可信度。分析结果表明,借助该模型,用户可以准确地选择可信的云服务提供商。

网格环境中基于SLA的本地任务调度算法

在服务网格中为用户提供满足SLA(service level agreement)的服务,是实现网格“非凡的服务质量”的一个重要的研究问题。本文提出了网格本地资源基于任务SLA的调度算法,给出了算法的数学模型和描述。在基于Java的网格环境调度模拟器中对算法进行了验证,该算法能实现满足用户SLA约束的调度,为满足全局的服务质量水平提供本地调度支持,对提高网格服务质量水平具有实际意义。

基于SLA的SaaSSP服务质量评价研究

以软件即服务(SaaS)模式中服务提供商(SaaSSP)的服务质量为研究对象,在SaaS电子服务质量评价指标实证研究的基础上获得评价维度和指标,结合由服务等级协议(SLA)形成的用户期望,采用SERVQUAL模型的服务质量差距思想,提出一种基于SLA的SaaSSP服务质量评价方法。算例结果表明,该方法能较好地融合服务质量差距理论与SaaS,为SaaS市场运营中软件服务提供商的服务质量评价提供参考。

一种基于QoS的QoE到SLA映射方法

该文提出一种算法IQoE2QoS(Improved QoE to QoS),采用模糊理论的方法计算QoE到QoS的映射。该算法有3重目标:从大量的经验数据中通过计算互信息量方式总结被统计指标之间的关联程度。在大量经验数据的基础上通过多指标模糊判定理论将用户感知映射到应用层用户QoS参数。考虑了用户的QoE和QoS的双向映射,并且阐述了得到的QoE如何自然映射到SLA(Service Level Agreement)。通过仿真表明,IQoE2QoS算法对用户体验的分类准确度是线性回归算法的2到3倍。

SLA参数定义方法及应用

业务等级协定(SLA)参数的定义是开发SLA模板的核心内容.在多提供商环境下新业务的开发需要定义不同层次SLA.目前还没有通用的SLA参数定义方法来支持SLA模板的开发.针对现有的需求和问题,本文提出了通用的SLA参数定义方法,系统地解决了一次性定义业务不同层次SLA参数的问题并在原型系统的设计和实现中应用了所提出的方法.

基于SLA的业务建模和参数映射算法

为了实现综合、准确的服务等级协定(SLA)业务管理,对SLA参数表示及参数映射进行了研究.首先,从不同的视角定义SLA表示参数,提出双向流程分析法提取表示参数,并利用参数映射机制研究各参数之间关系,建立多视点、层次化的SLA业务管理数据模型.其次,引入层次分析方法(AHP)结合不同的判别算法对各层参数进行关联计算,完成了各层参数间的映射.最后,在通用无线通信系统(UMTS)网络中建立文件传输(FTP)业务管理数据模型,并对参数映射算法进行验证.仿真结果表明了本方法的合理性和有效性.

基于SLA的业务质量评价

为了满足下一代互联网环境下的新的业务质量评价需求,本文研究了业务质量综合评价模型并提出了基于策略的业务质量评价系统体系结构,详细描述了业务质量评价过程。基于定义业务质量评价策略的需求,对策略核心信息模型进行了扩展,定义了业务质量评价策略信息模型。原型系统的实现验证了该体系结构能够实现动态、自动化、可扩展和定量的业务质量评价。

制造网格中基于SLA的资源管理模型研究

为确保制造网格平台提供的制造资源及服务能够达到使用者的功能与质量要求,建立了基于SLA的资源管理模型,并对模型中的资源调度算法进行了深入研究。该模型以制造资源的服务质量(QoS)属性为评价标准,以服务水平协议(SLA)为约束条件,通过资源调度方法和策略为消费者提供有质量保证的制造服务。最后,以快速成型制造为应用,验证了模型的实用性及资源调度算法的可行性。

云计算中的SLA管理技术研究

云计算环境中,用户的需求动态变化,云供应商不能掌控用户需求变化,但必须提供用户满意的服务质量,因此,QoS保证是云计算技术未来持续发展的关键。QoS保证通过SLA实现。本文综述了云计算SLA管理中的SLA指标分类、资源监测、SLA违例管理以及SLA参数映射技术的研究现状,最后指出了云计算中基于SLA的资源管理是未来的研究方向。

一种面向SLA的云计算环境下虚拟资源调度方法

云计算环境下,应用提供者可以根据需要决定租用虚拟资源的数量。租用大量资源会得到Qo S保障,从而获得较好的收益,但应用提供者需要为租用资源付费。同样,租用少量资源,会节省租用资源投入,但资源不足难以保障Qo S,SLA(Service Level Agreement)违背会带来经济损失。因此,租用多少虚拟资源才能使得资源得到充分利用,达到应用提供者的收益最大化成为亟待解决的问题。针对此问题,从应用提供者收益角度考虑,兼顾SLA收益损失和服务器租用成本投入,提出虚拟机资源调度方法,旨在使得应用租用者收益最大化。该方法利用排队论建模目标云应用的性能,并引入SLA收益损失函数估算在租用一定虚拟资源情况下的SLA收益损失,最后,利用爬山算法动态调整物理资源租用数量以达到收益最大化的目标。实验结果表明,与当前常见的虚拟机资源调度方法 1VMPer Job、1VM4All和Bin Packing相比,所提出的方法使得云应用提供者的成本投入分别降低了17.92%、22.85%和10.74%。