Cloud Service Level Agreement Research Articles

A Framework for Optimizing the Response Quality of Services in Mobile Cloud Computing Systems

subject of providing mobile users with an optimized service based on the Service Level Agreement (SLA) in cloud computing environment is one of the controversial issues, because there are a lot of challenging features in this environment such as the heterogeneity of cloud resources and also processing power of mobile phones. In this article, a framework called CSRAM is proposed for optimizing the response quality of services (QoS) in mobile cloud computing systems that tries to increase the precision and speed of the best service selection by offloading part of the computations to the cloud as well as using the context information of service provider in request adaptation process. In the proposed framework, it was tried to design a modular system and also to consider an appropriate algorithm for using in service request adaptation process. Finally, with regarding to seven effective environmental parameters as the inputs and also, with comparison between CSRAM framework and another applied framework, more flexibility was achieved in changing the environmental parameters of the problem, Reduction in the imposed computational load on user's mobile phone and also, increase in solution precision based on the reality.

TRUSTED CLOUD COMPUTING FRAMEWORK FOR HEALTHCARE SECTOR

Cloud computing is rapidly evolving due to its effi cient characteristics such as cost-effectiveness, availability and elasticity. Healthcare organizatio ns and consumers lose control when they outsource t heir sensitive data and computing resources to a third p arty Cloud Service Provider (CSP), which may raise security and privacy concerns related to data loss and misuse appealing threats. Lack of consumers’ knowledge about their data storage location may lea d to violating rules and regulations of Health Insu rance Portability and Accountability Act (HIPAA) that can cost them huge penalty. Fear of data breach by int ernal or external hackers may decrease consumers’ trust i n adopting cloud computing and benefiting from its promising features. We designed a HealthcareTrusted Cloud Computing (HTCC) framework that maintains security, privacy and considers HIPAA regulations. HTCC framework deploys Trusted Computing Group (TCG) technologies such as Trusted Platform Module (TPM), Trusted Software Stack (TSS), virtual Trusted Platform Module (vTPM), Trusted Network Connect (TNC) and Self Encrypting Drives (SEDs). We emphasize on using strong multi-factor authentic ation access control mechanisms and strict security controls, as well as encryption for data at storage , in-transit and while process. We contributed in customizing a cloud Service Level Agreement (SLA) by considering healthcare requirements. HTCC was evaluated by comparing with previous researchers’ work and conducting survey from experts. Results wer e satisfactory and showed acceptance of the framework. We aim that our proposed framework will assist in optimizing trust on cloud computing to be adopted i n healthcare sector.

SLA-based operations of massively multiplayer online games in clouds

Successful massively multiplayer online games (MMOGs) have today millions of registered users and hundreds of thousands of active concurrent players. To be able to guarantee quality of service (QoS) to a highly variable number of concurrent users, game operators statically over-provision a large infrastructure capable of sustaining the game peak load, even though a large portion of the resources is unused most of the time. To address this problem, we introduce in this work a new MMOG ecosystem for hosting and provisioning of MMOGs which effectively splits the traditional monolithic MMOG companies into three main service providers: game providers, game operators, and resource providers. Their interaction is regulated through comprehensive service level agreements (SLA) that establish the price, terms of operation, and compensation for service violations. In our model, game operators efficiently provision resources for MMOGs from multiple cloud providers, based on dynamic load forecasts, and ensure proper game operation that maintains the required QoS to all clients under varying resource availability. Game providers manage multiple distributed MMOGs for which they lease services under strict operational SLAs from game operators to satisfy all client requests. These three self-standing, smaller, more agile service providers enable access to the MMOG market for the small and medium enterprises, and to the current commercial cloud providers. We evaluate, through simulations based on real-life MMOG traces and commercial cloud SLAs, the impact of resource availability on the QoS offered to the MMOG clients. We find that our model can mitigate the negative effects of resource failures within four minutes and that MMOG server consolidation can accentuate the negative effects of failures in a resource-scarce environment. We further investigate different methods of ranking MMOG operational offers with either single or multiple (competing) MMOG providers. Our results show that compensations for SLA faults in the offer selection process can lead up to 11---16 % gain in the game providers' income. We also demonstrate that adequate ranking of offers can lead to MMOG operational cost reductions from 20 up to 60 %.

Towards service level agreements engineering process in cloud computing

Cloud computing becomes the most common product within IT markets and the global business in general. It offers a powerful and flexible resources and services including software as a service (SaaS), infrastructure as a service (IaaS) and platform as a service (PaaS). On the other hand, service level agreement (SLA) is a formal contract between the cloud vendors and providers, and customers including organisations and individuals. SLA is considered as an awkward process for both providers and customers since each part has a different understanding about its detailed structure, phases and embedded elements. In this paper, a fine-defined engineering model with five well-structured phases for managing SLA in a cloud environment is introduced. This SLA engineering model will benefit both cloud providers and consumers. It will allow providers to structure and organise the SLA correctly in attractive way for customers. Simultaneously, it will provide customers with the necessary and sufficient awareness to get a fair SLA for resources or services they may access. Also, a case study is presented to demonstrate how the proposed five phases utilised to construct the required SLA in a private cloud.

Adaptive and similarity-based tradeoff algorithms in a price-timeslot-QoS negotiation system to establish cloud SLAs

Since participants in a Cloud may be independent bodies, some mechanisms are necessary for resolving the different preferences to establish a service-level agreement (SLA) for Cloud service reservations. Whereas there are some mechanisms for supporting SLA negotiation, there is little or no negotiation support involving price, time slot, and QoS issues concurrently for a Cloud service reservation. For the concurrent price, timeslot, and QoS negotiation, a tradeoff algorithm to generate and evaluate a proposal which consists of price, timeslot, and QoS proposals is necessary. The contribution of this work is designing a multi-issue negotiation mechanism to facilitate 1) concurrent price, time slot, and QoS negotiations including the design of QoS utility functions and 2) adaptive and similarity-based trade-off proposals for price, time slots, and level of QoS issues. The tradeoff algorithm referred to as "adaptive burst mode" is especially designed to increase negotiation speed, total utility, and to reduce computational load for evaluating proposals by adaptively generating concurrent set of proposals. The empirical results obtained from simulations carried out using an agent-based testbed suggest that using the negotiation mechanism, (i) a consumer and a provider agent have a mutually satisfying agreement on price, time slot, and QoS issues in terms of the aggregated utility and (ii) the fastest negotiation speed with (iii) comparatively lower number of evaluated proposals in a negotiation.

Cloud SLAs

The variability in the service level agreements (SLAs) of cloud providers prompted us to ask the question how do the SLAs compare and how should the SLAs be defined for future cloud services. We break down a cloud SLA into easy to understand components and use it to compare SLAs of public cloud providers. Our study indicates that none of the surveyed cloud providers offer any performance guarantees for compute services and leave SLA violation detection to the customer. We then provide guidance on how SLAs should be defined for future cloud services.