Achieving Service Level Agreement in Cloud Environment Using Job Prioritization in Hierarchical Scheduling

This work presents a novel scheme for Service Level Agreements (SLAs) in a service-oriented architecture (SOA). An SLA is a contract that guarantees quality of service (QoS) between service providers and consumers. An SLA can be split into several parts for an SOA system which is consisting of different services. A split SLA is used to guarantee quality of services for one of services in an SOA system. However, these contract rules do not regulate follow-up process in services. SLA violations may occur consequently. For instance, interactions between services are not encrypted because the encryption parameter isn't included in the split SLA contract. Confidential data would be transmitted through unsafe channels. There would be a security issue of SLA Management for follow-up processes in an SOA system. The novel scheme in this work addresses these problems. Using SLAs management proposed in this work can identify the services that consumer needs and split the contracts for follow-up services. SLAs are not only guaranteed between service providers and consumers but also assured in follow-up processes. The proposed method improves the security and completeness of SLA using in an SOA system.

An Service Level Agreement (SLA) is a contract between service provider and consumer, and includes appropriate actions to be taken upon violation of the contractual obligations. To ensure the negotiation on an SLA is reasonable by reference the measured history data. The paper proposes a feasible Web Service Level Agreement (WS-SLA) Establishing Framework, which can flexible define trustable SLA requirements and penalties actions upon service providers based on monitoring data from service consumer. Web service QoS (WS-QoS) Monitor provides the automatic approach for measureing Quality of Service (QoS) parameters from service requester side. WS-SLA Editor allows service consumer to flexible define their SLA requirement and penalties actions upon service providers.

Business-to-Business (B2B) applications are developed predominantly based on service-oriented architectural style which is generally realized using a set of loosely coupled web services. These web services can be selected statically during design-time or dynamically during run-time. The functional and non-functional QoS requirements are typically captured in the Service Level Agreement (SLA) that is mutually agreed between the service provider and the service consumer. Whenever an SLA violation happens, the service provider incurs a penalty. In order to minimize such penalties, the application that is built through a design-time composition of web services needs to be monitored. Whenever a violation of SLA is predicted, those statically composed web services are dynamically reconfigured. This is called as dynamic reconfiguration in SOA. In this case, even the alternate service selection happens at design-time itself. On the other hand, whenever the web services needed for an SOA application development are selected and composed dynamically at run-time, it is called as dynamic composition. The turnaround time involved in both these approaches for mission-critical applications with stringent SLA requirements is compared. It has been inferred that the dynamic reconfiguration approach not only maintained the turnaround time always within the accepted limits, it also incurred only less overhead when compared to dynamic composition approach.

Online service is used to be as Pay-Per-Use in Cloud computing. Service user need not be in a long time contract with cloud service providers. Service level agreements (SLAs) are understandings marked between a cloud service providers and others, for example, a service user, intermediary operator, or observing operators. Since cloud computing is an ongoing technology giving numerous services to basic business applications and adaptable systems to manage online agreements are significant. SLA maintains the quality-of-service to the cloud user. If service provider fails to maintain the required service SLA is considered to be SLA violated. The main aim is to minimize the SLA violations for maintain the QoS of their cloud users. In this research article, a toolbox is proposed to help the procedure of exchanging of a SLA with the service providers that will enable the cloud client in indicating service quality demands and an algorithm as well as Negotiation model is also proposed to negotiate the request with the service providers to produce a better agreement between service provider and cloud service consumer. Subsequently, the discussed framework can reduce SLA violations as well as negotiation disappointments and have expanded cost-adequacy. Moreover, the suggested SLA toolkit is additionally productive to clients so clients can secure a sensible value repayment for diminished QoS or conceding time. This research shows the assurance level in the cloud service providers can be kept up by as yet conveying the services with no interruption from the client's perspective

One major issue of cloud computing is developing Service Level Agreement (SLA)-oriented cloud management system, because situations like resource failures may lead to the violation of SLA by the provider. Several research works has been carried out regarding cloud management system were the impact of SLA is not properly addressed in the perspective of resource failure. In order to achieve SLA in such circumstance, a novel-layered architecture of SLA-oriented Cloud Management System (SLAOCMS) is proposed for service provisioning and management which highlight the importance of various components and its impacts on the performance of SLA- based jobs. There are two components such as Task Scheduler and Load Balancer which are introduced in SLA Management Framework to achieve SLA during resource failure. So, an SLA Aware Task Scheduling Algorithm (SATSA) and SLA Aware Task Load Balancing Algorithm (SATLB) are proposed in the above components to improve the performance of SLAOCMS by successfully achieving the SLA’s of all the user jobs. The results of traditional and proposed algorithms are compared in the scenario of resource failure with respect to violations of SLA-based jobs. Moreover, SLA negotiation framework is introduced in application layer for supporting personalized service access through the negotiation between the service consumer and service provider.

Cloud computing and Internet of Things (IoT) are computing technologies that provide services to consumers and businesses, allowing organizations to become more agile and flexible. The potential business values that cloud consumers can achieve depend a lot on the quality of service in the provided cloud services. Therefore, ensuring the quality of service through service-level agreements (SLA) for such cloud-based services is crucial for both the service providers and service consumers. As SLA is critical for cloud deployments and wider adoption of cloud services, the management of SLA in cloud and IoT has thus become an important and essential issue. In this paper we provide an understanding of the current status and maturity level of SLA management in industrial IoT and academic efforts in this field. We also conduct a preliminary survey of current research on SLA management in order to identify open challenges and gaps that need to be addressed in future research directions. In particular, we investigate how to provide useful SLA management support adapted to the maturity level and current industrial practices, and shorten the gap between academia and industry.

Nowadays, Cloud providers revise the terms of their Service Level Agreements (SLAs) to include security provisions due to their criticality for their customers. In order to speed up their adoption by service providers and consumers and to make them more actionable, security SLAs monitoring should be described in a machine-processable, agile and extensible way. Several tools for SLA management are available on the market but most deal with performance metrics and do not refer to security properties. There are other tools for monitoring cloud security, in a non-SLA way. However, they are not associated with SLA management systems. We propose an extension to an SLA language (i.e., rSLA) to enable the description of security requirements in an SLA document. We also extend the rSLA framework by a security methodology that makes use of known tools and that enables continuously checking that the security requirements are respected during runtime according to the SLA document.

A Service Level Agreement (SLA) establishes the trustworthiness of service providers and consumers in several domains; including the Internet of Things (IoT). Given the proliferation of Blockchain technology, we find it compelling to reconsider the assumption of trust and centralised governance typically practised in SLA management including monitoring, compliance assessment, and penalty enforcement. Therefore, we argue that, such critical tasks should be operated by blockchain-based smart contracts in a non-repudiable manner beyond the influence of any SLA party. This paper envisions an IoT scenario wherein a firefighting station outsources end-to-end IoT operations to a specialised service provider. The contractual relationship between them is governed by an SLA which stipulates a set of quality requirements and violation consequences. The main contribution of this paper lies in designing, deploying and empirically experimenting a novel blockchain-based SLA monitoring and compliance assessment framework in the context of IoT. This is done by utilising Hyperledger Fabric (HLF), an enterprise-grade blockchain technology. Our work highlights a set of considerations and best practice at two sides, the IoT application monitoring-side and the blockchain-side. Moreover, it experimentally validates the reliability of the proposed monitoring approach, which collects relevant metrics from each IoT component and examines them against the quality requirements stated in the SLA. Finally, we propose a novel design for smart contracts at the blockchain-side, analyse and benchmark the performance, and demonstrate that the new design proves to successfully handle Multiversion Concurrency Control (MVCC) conflicts typically encountered in blockchain applications, while maintaining sound throughput and latency.

Cloud services are offered to consumers based on Service Level Agreements (SLAs) signed between Cloud Service Provider (CSP) and consumer. Due to on-demand provisioning of resources there is exponential growth of cloud consumers. Job scheduling is one of the areas that has attracted researchers to improve performance of cloud management system. Along with the on premise infrastructure, Small and Medium Enterprises (SMEs) also depend on public cloud infrastructure (leading to hybrid cloud) for seamless continuity of their businesses. In this context, ensuring SLAs and effective management of hybrid cloud resources are major challenging issues to be considered. Hence, there is a need for an effective scheduling algorithm which considers multiple objective functions like SLA (deadline), cost and energy while making scheduling decisions. Most of the state of the art schedulers in hybrid cloud environment considered single objective function. However, in real world, it is inadequate for scheduling effectiveness. To overcome this problem, we proposed an integrated framework which ensures SLAs (deadline), cost effectiveness and energy efficiency with an underlying scheduling algorithm known as SCE-TS. This algorithm is evaluated with different workloads and SLAs using a cloud platform. The empirical study revealed that the proposed framework improves scheduling efficiency in terms of meeting SLAs, cost and energy efficiency. It is evaluated and compared with the state of the art and found to be effective in making scheduling decisions in cloud environment.

Currently, from the customer's opinion, the establishment and monitoring of Service Level Agreements (SLA) between cloud service consumers (CSC) and cloud service providers (CSP) is far to be ideal. This contacts require crucial importance for consumers having companies whose success is conditioned by the announced Quality of Service (QoS) that the service provider delivers. Inflexible term and price conditions, nontransparent verification of advertised service quality, and inflexible expression of SLAs represent today the most gap in terms of SLAs on the cloud market. This paper presents an approach of an autonomous framework based Agreement-Broker as a third party in the cloud market that provides a way to source out tasks regarding the management of SLAs. Thus the Agreement-Broker adds an additional transitive connection between consumers and providers without affecting any existing one. The Agreement-Broker's main purposes are: –Registering declarations in the form of established SLAs; –Giving customers the opportunity to discover provided SLAs and to easily compare them; –Notifying participating parties about agreementrelated events like creation, violation or termination Thus, the overhead for managing SLAs which causes congestion between consumers and providers is minimized for both and a higher trust is established by broker of an external entity.

The concept of presence was initially associated with an instant messaging service, allowing an end user to recognize the presence of a peer online to send or receive messages. Now the technology has grown up to include various services like monitoring performance of any type of end user device, and services are accessible from anywhere, any time. The need for enhanced value remains the driving force behind these services, for example, Voice over Internet Protocol (VoIP) services, which is drawing tremendous research interest in services performance evaluation, measurement, benchmarking, and monitoring. Monitoring service level parameters happens to be one of the most interesting application-oriented research issues because various service consumers at the customer companies/end users’ level are finding it very difficult to design and monitor an effective SLA (Service Level Agreement) with the presence-enabled service providers. This chapter focuses on to these specific issues and presents a new approach of SLA monitoring through Data Envelopment Analysis (DEA). This extreme point approach actually can work much better in the context of SLA monitoring than general central-tendency-based statistical tools, a fact which has been corroborated by similar application examples of DEA presented in this chapter and has therefore it acts as the primary motivation to propose this new approach. Towards this end, this chapter first builds up the context of presence-enabled services (Day, Rosenburg, & Sugano, 2000), its SLA and SLA parameters, and the monitoring requirements. Then it explains the basics of DEA and its application in various other engineering and services context. Ultimately, a DEA application framework for monitoring an SLA of presence-enabled services is proposed which can serve as a clear guideline for the customers of presence-enabled services, not only for SLA monitoring but also at various other stages of implementing presence-enabled services frameworks. This approach exploits the definitive suitability of the application of DEA methods to presence-enabled service monitoring problems, and can be easily implemented by the industry practitioners.

Service Level Agreements (SLAs) are the means through which the provision of infrastructure, platform, and software services in Cloud Computing is regulated, along with functional and non-functional specifications of services. SLAs are intended to set a framework for the provision of services and for the cooperation between service providers and service consumers. Currently, Cloud SLAs are usually drafted by Cloud providers and do not allow much negotiation. Therefore, it becomes critical to analyze and assess if, and to what extent, the rights and the expectations of Cloud users (in particular private consumers and small and medium-sized enterprises) are respected by these SLAs and by existing legal mechanisms. With this perspective, in this chapter, we analyze whether the current Cloud SLAs are sufficiently in accordance with rights (if any) and business expectations of users in protecting their data concerns and whether they are able to establish trust between Cloud consumers and Cloud providers.

Cloud computing is very promising technology to deliver computing resources like infrastructure (IaaS), platform (PaaS), software (SaaS) etc. in form of services over the Internet. Server consolidation is the mechanism to minimize active (running) physical servers in the data center of cloud service provider. Consolidation helps the service provider to make efficient usage data center resources and in turn to minimize running cost of data center. Users have to pay as per service usage. SLA is like contract between cloud service provider and users. Service Level Agreement (SLA) is the mechanism of providing guaranteed services to cloud users. SLA Violation may cause high penalties to service provider. In this paper it is shown that if consolidation is maximized, it may cause more number of SLA violation. A balanced approach of server consolidation with minimal SLA violations is suggested in this paper.

Currently several enterprises depend on services provided to them by other parties for the realization of their own service offer. The interconnections in terms of services offered and required by companies shape complex systems, called service networks. The new cloud-computing paradigm is stressing the concept of the governance of relationship between IT customers and providers. The relationship is based on Service Level Agreements (SLA) and obligations, described inside contracts between providers and customers. Every customer needs to agree with a SLA in order to lease a new service. SLAs describe provisioning terms and encapsulate QoS characteristics as well as functional properties. Traditionally, providers define SLAs in which they guarantee explicit provisioning service level bounds for an agreed period. In the scientific literature, SLAs are hardly viewed as end-user documents, and merely as automated processes that assist the monitoring and scheduling of resources. In contrast, cloud IT marketplaces treat SLAs as static documents that do not allow for any processing. Moreover, strong diversity exists in how service providers coming from distinct business and socio-economical domains formulate and exercise their provisioning responsibilities. Such issues need to be resolved in order to make SLAs enacting tools for managers and services' providers in order to govern contracts. The contribution of this paper is to discuss some relevant open issues not covered by current contract management approaches and tools. In particular we will explore how service composition, with specific focus on service levels, limits and shapes technical, legal and organizational aspects related to the contract of the composed service.

Service level agreement (SLA) is a formal contract between a service provider and a service consumer to guarantee the Quality of service (QoS) expectations, it is used in all areas of information technology, such as Cloud Computing, Internet of Things (IoT), networks and Web services. For IoT applications, the main challenges are: (1) how to describe the SLA terms, such as QoS properties, service levels, penalties in SLA violation, (2) how to monitor these terms, and (3) how to integrate an SLA into all the IoT application layers. Therefore, in this paper, we propose ML-SLA-IoT, a framework for SLA specification and monitoring. It covers the entire layers of an IoT application. It describes precisely QoS levels, provided services, and obligations. It differs from other SLA specification languages in the specification of user preferences, the use of microservices (for reusability, dynamism and ease of integration) and ML-SLA (multi-level metrics and QoS according to existing constraints and user preferences). Furthermore, ML-SLA-IoT monitors SLA terms in an automatic and decentralised manner using smart contracts and blockchain technologies without the intervention of the third-party. Finally, we present a comparative study and experiments with existing solutions regarding to some criteria for SLA specification and monitoring. Our results show that ML-SLA-IoT gives better performance in terms of dynamic pricing, obligation combination, and SLA monitoring.