SLA management in federated environments

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.

Service Level Agreement (SLA) is an important document to facilitate IT service provisioning by clearly defined Quality of Service (QoS) parameters. The management of SLA is the main subject in the discipline of Service Level Management (SLM) . SLM is very important to improve relationship between IT service provider and its customer. It delivers documented agreement as a common understanding of expectation and possible achievements to the agreed cost. It means SLM builds the interface between an IT organization and its cust omer, so it plays a critical and important role in the context of IT service management. In this paper, an SLM best practice from CISCO will be analyzed with the assessment criteria of SLM framework by Thomas Schaaf. The result will be followed with several suggestion to fulfil the gap in this CISCO’s best practice.

A service level agreement (SLA) is a service contract that includes the evaluation criteria for agreed service quality standards. Since agreeable specifications on the evaluation criteria cannot be limited in practice, competitive SLA management products must be extensible in terms of their support for contract-specific SLA compliance evaluations. While the need of running and managing those software products as services increases, we have found that developing a good solution for configuring them as per contractual terms is a challenging task. This paper presents the Fresco framework, which facilitates configuring extensible SLA management systems using Web services. An XML-based specification of SLA management related data called SCOL will also be presented to show how the framework supports contract-specific SLA terms and contract-specific extensions of the deployed SLA management software. The paper furthermore shows how the Fresco system uses a template-based approach to communicate with other Web services applications with support for various input and output formats. Our experience with implementing the Fresco framework for a leading commercial SLA management software product demonstrates that the framework facilitates the creation of effective and efficient solutions for configuring extensible SLA management systems.

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.

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.

A Service Level Agreement (SLA) is a legal contract between parties to ensure the Quality of Service (QoS). It specifies one or more service level objectives (SLO), to ensure that the QoS delivered has met customer expectations. However, It becomes hard to guarantee QoS levels and detect SLA violations. Therefore, we propose to use MDE (Model Driven Engineering) to express the SLA contract requirements. This latter, created with a specific modeling language (DSML), will be used harmonically with a Multi-agent systems (MASs) in order to monitor SLA violations in real-time. Indeed, MASs are suitable tools for self-detection of failures and self-monitoring of cloud operations and services, QoS negotiation and SLA management. They are designed to operate in a dynamically changing environment. Our main motivation is firstly to use MDE technology for the creation of the SLA contract and then to integrate MASs in order to control the quality of service contract and guarantee transparency and symmetry with respect to the SLA contract between prospective signatories.

The efficient management of a quality level of Internet service is becoming increasingly important to both customers and service providers. This article describes how service level agreements for multimedia Internet service can be managed and controlled. We first present a literature survey on the problems of SLA management: SLA parameter definition, SLA measurement, and QoS management. We present a utility model to capture the management and control aspects of SLAs for multimedia Internet service. This utility model has been used in microeconomics theory, but here we have applied it to SLA management. This model provides a computationally feasible solution for admission control and quality adaptation for multimedia Internet service and SLA management. It also allows management policies to be flexibly expressed by service providers. Finally, we apply the utility model to the SLA management of VoIP service and describe how to use it for admission control, dynamic quality adaptation, and resource allocation for SLA assurance.

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.

The emerging transformation from a product oriented economy to a service oriented economy based on Cloud environments envisions new scenarios where actual QoS (Quality of Service) mechanisms need to be redesigned. In such scenarios new models to negotiate and manage Service Level Agreements (SLAs) are necessary. An SLA is a formal contract which defines acceptable service levels to be provided by the Service Provider to its customers in measurable terms. SLAs are an essential component in building Cloud systems where commitments and assurances are specified, implemented, monitored and possibly negotiable. This is meant to guarantee that consumers’ service quality expectations can be achieved. In fact, the level of customer satisfaction is crucial in Cloud environments, making SLAs one of the most important and active research topics. This paper presents an SLA implementation for negotiation, monitoring and renegotiation of agreements for Cloud services based on the CMAC (Condition Monitoring on A Cloud) platform. CMAC offers condition monitoring services in cloud computing environments to detect events on assets as well as data storage services.

We consider whether the off-line compilation of a set of Service Level Agreements (SLAs) into low-level management policies can lead to the runtime maximization of the overall business profit for a service provider. Using a simple Web application hosting SLA template for a utility service provider, we derive low-level QoS management policies and validate their consistency. We show how the default first come first served (FCFS) mechanism for the runtime scheduling of triggered policies fails to deliver an all times maximum business profit for the service provider. To achieve a better business profit, first a penalty/reward model that is derived from the SLA Service Level Objectives (SLOs) is used to assign runtime utility tags to triggered policies. Then three policy scheduling algorithms, which are based on the prediction of the future state of the running SLAs, are used to drive the runtime actions of the Policy Decision Point (PDP). The prediction function per see involved the unsolved problem of predicting in realtime the evolution of the transient state of a variant of an M/M/Ct/Ct queue. A simple approximative solution to the latter problem is provided. Finally, using the VS policy simulator tool, comparative simulation results for the business profit generated by each of the proposed policy scheduling algorithms are presented. VS is a novel tool which we have developed to respond to the increasing need of benchmarking SLA and policy-based management solutions.

Service Level Agreements (SLAs) aims at offering a simple and clear way to build up an agreement between the final users and the service provider in order to establish what is effectively granted by the cloud providers. In this paper we will show the SLA-related activities in mOSAIC, an european funded project that aims at exploiting a new programming model, which fully acquires the flexibility and dynamicity of the cloud environment, in order to build up a dedicated solution for SLA management. The key idea of SLA management in mOSAIC is that it is impossible to offer a single, static general purpose solution for SLA management of any kind of applications, but it is possible to offer a set of micro-functionalities that can be easily integrated among them in order to build up a dedicated solution for the application developer problem. Due to the mOSAIC API approach (which enable easy interoperability among moSAIC components) it will be possible to build up applications enriching them with user-oriented SLA management, from the very early development stages.

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.

The advent of information and communication technology has changed the nature of business-to-business interaction among organizations. The use of electronic contracts with automated support for their management allows an increase of effectiveness and efficiency in contract processing, opening new possibilities for interaction among parties. Service Providers and their customers negotiate utility based Service Level Agreements (SLA) to determine costs and penalties based on the achieved performance levels. The global QoS to be provided to the end customer can be strongly affected by any violation on each single SLA. In order to prevent such violations, SLAs need to be flexible and dynamically adaptable. In this work we focus on the WS-Agreement specification, a Web Service protocol to establish agreements on the QoS level to be guaranteed in the provision of a service. We propose to enhance the flexibility of its approach by integrating new functionality to the protocol that enable the parties of a WS-Agreement to re-negotiate and modify its terms during the service provision.

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.

By leveraging the Internet, cloud computing allows users to have on-demand access to large pools of configurable computing resources. PaaS (Platform as a Service), IaaS (Infrastructure as a Service), and SaaS (Software as a Service) are three basic categories for the services provided by cloud the computing environments. Quality of service (QoS) metrics like reliability, availability, performance, and cost determine which resources and services are available in a cloud computing scenario. Provider and the user-specified performance characteristics, such as, rejection rate, throughput, response time, financial cost, and energy consumption, form the basis for QoS. To fulfil the needs of its customers, cloud computing must ensure that its services are given with the appropriate quality of service QoS. A “A legally enforceable agreement known as a “Service Level Agreement” (SLA) between a service provider and a customer that outlines service objectives, quality of service requirements, and any associated financial penalties for falling short. We, therefore, presented “A Proactive Resource Supply based Run-time Monitoring of SLA in Cloud Computing”, which allows for the proactive management of SLAs during run-time via the provisioning of cloud services and resources. Within the framework of the proposed work, SLAs are negotiated between cloud users and providers at run-time utilizing SLA Manager. Resources are proactively allocated via the Resource Manager to cut down on SLA violations and misdetection costs. As metrics of performance, we looked at the frequency with which SLAs were broken and the money lost due to false positives. We compared the proposed PRP-RM-SLA model’s simulated performance to the popular existing SLA-based allocation strategy SCOOTER. According to simulation data, the suggested PRP-RM-SLA model is 25% more effective than the current work SCOOTER at reducing SLA breaches and the cost of misdetection.