Differentiated services traffic conditioner based on Token Buckets and Time Sliding Window

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

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.

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 contract between the service provider (SP) and the customer. Among various parameters, SLA imposes penalties on the SP when the customer's quality-of-service (QoS) requirements are violated. Hence, it is desirable to avoid SLA violations and such penalties. SLA also states the maximum amount of downtime a connection may tolerate during its lifetime. In this study, we present a dynamic provisioning scheme called Preemption-Oriented SLA-Aware Provisioning (POSAP) for telecom mesh networks, which considers a connection's (1) availability requirements, (2) penalty, and (3) state. In addition to the connection's various parameters (availability, penalty, etc.), the amount of affordable downtime is used as a metric to determine the risk of violating the connection's SLA, and hence, its priority. Connection's priority is denoted by urgency level. Our scheme allows resource preemption among connections, i.e., high-priority connections may preempt backup resources from low-priority connections. Also, new connection requests may preempt resources from existing connections. Urgency level determines how resources can be preempted. Our scheme is applied to a US-wide network. Our results show the improved performance in terms of (1) reduced SLA violations, (2) increased network utilization, and (3) increased network revenue, compared to a dedicated primary-backup (P-B) scheme.

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.

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.

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.

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.

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.

Achievable quality of service (QoS) among flows with disparate metrics in Differentiated Services (Diffserv) presents challenges for network edge traffic conditioners. A fair traffic conditioner was presented by M. El-Gendy and K. Shin in [1]. It provides fairness guarantees by inverting a form of the TCP rate equation as an edge conditioner. It achieves fairness by conditioning all flows regardless of the individual characteristics. We analyzed this conditioner in [2] for effectiveness and provided an enhancement in the area of packet loss rate estimation. We have continued our research and our new contributions are two fold. We present a trend factor in TCP loss rate dynamics and its effect on traffic conditioning. Here, we employed the Holt-Winters algorithm which integrates trend measurement in loss rate estimation. We also investigated the effect of the Time Sliding Window algorithm as a rate estimator on the trend factor and how it affects packet marking. We have analyzed the effectiveness of these two working in tandem in the achievement of fairness in Diffserv.

One of the challenging issues in Cloud computing Environment is meeting the Service Level Agreement (SLA). The SLA is an agreement signed between the service provider and the service consumer for accessing the service provided by the service provider over the internet. We can investigate the negotiation strategy between the service provider and the service consumer through the third party called a Broker. In many approaches SLA is designed and trusted through the measurement of various non-functional requirements such as response time of job, CPU usage, memory usage and the storage used by the consumer. Main focus of the business process is satisfying the customer need by quick response. In our proposed approach for satisfying the service consumer (customer), parameter such as response time of deadline based job is considered. The response time of the job is affected due to improper scheduling of the job. Therefore a novel hierarchical scheduling with job prioritization is used to give more priority for deadline based jobs. This approach will satisfy the service consumer and meet the SLA by increasing the performance of the scheduling algorithm.

In the last decade, Service Level Agreements (SLAs) play a pivotal role in Cloud Computing especially for guaranteeing quality, availability and responsibility. SLA involves different actors including customers and service providers. The problem that arises is how to establish an SLA contract between those actors and especially how to help the customer to choose the provider that offers the adequate services. Another important point is the measures to guarantee that the provider respects its contract with the consumer. Our approach embraces model driven engineering principles to automate the generation of the SLA contract and its real-time monitoring. For this purpose, we propose three languages dedicated respectively to the customer, the supplier, and the contract specification. Since we cannot predict QoS values at advance, we propose to use machine learning to learn QoS behavior at run-time.

In this paper, the work is carried upon the security of cloud computing environment from the economic denial of service (EDOS) attacks. The cloud computing environments have become popular in the past decade, as number of businesses has shifted their work online to the cloud. The cloud service providers offer the maximum uptime for their users, which is committed in the form of service level agreements (SLAs). The uptime is the term used to indicate the availability of the cloud computing resources for client's application to run its processes. If at any point, the client application is not able to run its operations due to non-availability of resources, it is considered as the downtime, which is negative to the uptime and considered as SLA violation. The SLAs keep the information about the SLA violations and their settlements, which is considered as the loss of the cloud service providers. For example, the uptime of 99.99% is committed by cloud service provider, and due to any internal or external reason, achieved uptime is lower than committed value, the cloud service provider may face a penalty as per defined in the SLA, which is considered direct profit loss for the service provider. In order to reduce the financial losses due to the EDOS attacks, the proposed model is designed by combining the periodic authentication, pattern analysis and data flow control mechanisms to prevent the cloud from attacks. The proposed Multi-Layered Attack Recognition (MLAR) Model has outperformed the existing controlled access based EDOS (CA-EDOS) prevention model on the basis of resource utilization and response delay parameters.

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.