In hosting environments such as Infrastructure as a Service (IaaS) clouds, desirable application performance is typically guaranteed through the use of Service Level Agreements (SLAs), which specify minimal fractions of resource capacities that must be allocated by a service provider for unencumbered use by customers to ensure proper operation of their workloads. Most IaaS offerings are presented to customers as fixed-size and fixed-price SLAs, that do not match well the needs of specific applications. Furthermore, arbitrary colocation of applications with different SLAs may result in inefficient utilization of hosts' resources, resulting in economically undesirable customer behavior. In this thesis, we propose the design and architecture of a Colocation as a Service (CaaS) framework: a set of strategic and operational services that allow the efficient colocation of customer workloads. CaaS strategic services provide customers the means to specify their application workload using an SLA language that provides them the opportunity and incentive to take advantage of any tolerances they may have regarding the scheduling of their workloads. CaaS operational services provide the information necessary for, and carry out the reconfigurations mandated by strategic services. We recognize that it could be the case that there are multiple, yet functionally equivalent ways to express an SLA. Thus, towards that end, we present a service that allows the provably-safe transformation of SLAs from one form to another for the purpose of achieving more efficient colocation. Our CaaS framework could be incorporated into an IaaS offering by providers or it could be implemented as a value added proposition by IaaS resellers. To establish the practicality of such offerings, we present a prototype implementation of our proposed CaaS framework.

Currently, many industrial companies generate many losses in their after sales this is generated to an error in the control of inventories and in turn in a mishandling of their assets through their processes, therefore the present research proposes a management model of processes and control of inventories in order to reduce customer losses due to the large number of existing complaints and thus increase sales. Therefore, the process management model, which will contribute to the standardization, optimization and control of its critical processes, and for which indicators, procedures and policies will be proposed for each stage of the process in order to measure its efficiency and effectiveness for correct decision making. With respect to the control of inventories, it is proposed to make a segmentation of the products, which allows the identification of the most important products for the company, to then design a demand forecast model for families of products that will later be individualized considering their factors initial and finally using an inventory management model will obtain the optimal quantity of spare parts order to use in the technical service of the equipment reducing the annual costs related to the inventory.

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We study techniques to enforce and provision differentiated service levels in Computational Grid systems. The Grid offers simplified provisioning of peak-capacity for applications with computational requirements beyond local machines and clusters, by sharing resources across organizational boundaries. Current systems have focussed on access control, i.e., managing who is allowed to run applications on remote sites. Very little work has been done on providing differentiated service levels for those applications that are admitted. This leads to a number of problems when scheduling jobs in a fair and efficient way. For example, users with a large number of long-running jobs could starve out others, both intentionally and non-intentionally. We investigate the requirements of High Performance Computing (HPC) applications that run in academic Grid systems, and propose two models of service-level management. Our first model is based on global real-time quota enforcement, where projects are granted resource quota, such as CPU hours, across the Grid by a centralized allocation authority. We implement the SweGrid Accounting System to enforce quota allocated by the Swedish National Allocations Committee in the SweGrid production Grid, which connects six Swedish HPC centers. A flexible authorization policy framework allows provisioning and enforcement of two different service levels across the SweGrid clusters; high-priority and low-priority jobs. As a solution to more fine-grained control over service levels we propose and implement a Grid Market system, using a market-based resource allocator called Tycoon. The conclusion of our research is that although the Grid accounting solution offers better service level enforcement support than state-of-the-art production Grid systems, it turned out to be complex to set the resource price and other policies manually, while ensuring fairness and efficiency of the system. Our Grid Market on the other hand sets the price according to the dynamic demand, and it is further incentive compatible, in that the overall system state remains healthy even in the presence of strategic users. / QC 20101116

Supply chain agility has been receiving a lot of attention in recent literature as a way for organizations to become more responsive to change and improve customer service levels. However, agility is typically dealt with qualitatively, and organizations are usually unsure of the steps to take to improve their agility and the customer service level to target. This research studies supply chain agility based on a case study of Intel Corporation, a large semiconductor manufacturer. Here, agility is defined as the ability to satisfy customer demands by reacting effectively to changes in market stimuli. Reacting effectively does not mean reacting to every change in supply or demand. Doing so means increasing supply chain variability unnecessarily, which is amplified by the bullwhip effect. The essence of supply chain agility is determining the degree to which variability should be managed through artificial means such as safety stock, and appropriate triggers for changing production levels and inventory targets. The purpose of this research is to examine factors that influence supply chain agility and identify a cost-effective plan for achieving it. The first phase addresses the problem of identifying target inventory and customer service levels based on regression analysis of historical data and financial analysis of inventory holding costs and stock-out costs. The impact of three factors (forecast error, order lead-time, and demand variability) on the relationship between inventory and customer service level is also examined. The second phase of the research evaluates strategies for production and inventory control with the goal of finding the appropriate trade-off between minimizing cost (of holding inventory and stock-outs) and minimizing variability. Control policies based on the Exponentially Weighted Moving Average (EWMA) control chart with control limits on demand forecasts are proposed to detect when tighter control of processes is necessary. A Monte Carlo supply chain simulation is used to evaluate the performance of these policies under various levels of forecast error and demand variability. Results indicate that several control chart-based policies outperform Intel's current planning policy in terms of cost without significantly increasing variability. The selection of the appropriate policy must be based on the decision-makers' desire to minimize cost compared to the desire to minimize variability, as each policy results in a trade-off between these two objectives.

Purpose: The purpose of this study was to analyze possible strategies that can be used to improve the efficiency of the spare parts safety stock management in a multinational company which operates in the electronic industry. Research question: “Which safety stock dimensioning strategies are most suitable in an after-sales business environment, characterized by high level customer service and unpredictable demand?” Method: The theoretical framework illuminated the study’s phenomenon which was mainly based on peer-reviewed scientific articles but also academic books. Furthermore, the empirical data collection in this study was conducted through a mixed research approach, where the qualitative data was collected through three semi-structured interviews and several unstructured interviews, while the quantitative data consisted of calculations using numerical variables provided by the case company. Conclusion: The study concluded that the so called estimated safety stock method as well as the probabilistic demand based on history method are the most suitable safety stock dimensioning strategies to utilize in business environments where firms that offer products with unpredictable demand are facing challenges related to finding a balance between providing a high service level and keeping their costs as low as possible. / Syfte: Syftet med denna studie var att analysera möjliga strategier som kan användas för att förbättra säkerhetslagerhanteringen av reservdelar hos ett globalt företag inom elektronikindustrin. Frågeställning: “Vilka dimensioneringsstrategier för säkerhetslager är mest lämpliga i en eftermarknadsverksamhet, kännetecknad av hög servicenivå och oförutsägbar efterfrågan?” Metod: Det teoretiska ramverket belyste studiens fenomen som var baserad på främst expertgranskade vetenskapliga artiklar men även böcker. Vidare genomfördes den empiriska datainsamlingen i denna studie genom en mixad forskningsmetod, där den kvalitativa datan var i form av fyra semistrukturerade intervjuer samt flera ostrukturerade intervjuer, medan den kvantitativa datan bestod av beräkningar med hjälp av numeriska variabler tillhandahållna av fallföretaget. Slutsats: Studiens slutsatser visade att den så kallade manuellt bedömt säkerhetslager metoden samt probabilistisk efterfrågan baserad på historisk data metoden är de mest lämpliga dimensioneringsstrategier för säkerhetslager att använda i affärsmiljöer där företag som erbjuder produkter med oförutsägbar efterfrågan står inför utmaningar relaterade till att hitta en balans mellan att tillhandahålla en hög servicenivå och att ha så låga kostnader som möjligt.

Small companies and organizations have expressed doubts about using cloud services due to unclear Service Level Agreement (SLA) contracts. These contracts are usually based on security frameworks and measures adapted for data security in general, but not for complex cloud data specifically. The purpose of this study was therefore to compare end users’ opinions of the security measures and security frameworks that were being used for their SLA contracts for cloud services. The study was carried out through semi-structured interviews, thematization, and comparison with earlier research on SLA and cloud security. The result showed that security frameworks on which SLA contracts were based were being used in a too general way by cloud service providers. This made the contracts unclear and not entirely relevant to their own operations. Therefore, the users wanted implementations of security measures that were easier to interpret, well-established and recognized, and relevant to their own operations. The users wanted the security measures to be more detailed by having the cloud service providers divide them into more categories relevant to their particular activities. The users also wanted SLA contracts adapted to their individual needs for cloud security specifically. One conclusion was that frameworks such as ISO, NIST, and COBIT were being used in a too general way for generating cloud service SLAs. Another conclusion was that cloud service security measures should be more specific to users’ own operations and easier to interpret in relation to established frameworks. Cloud service providers could use NIST, ISO, and COBIT to generate more specific measures. One solution would be to automatically generate more specific SLA contracts by auto-selecting established frameworks and well-defined security measures.

Denna rapport belyser aspekter som kunder borde vara medveten om vid kontraktering med en molnleverantör. Molntekniken är effektiv, skalbar och relativt enkel att implementera, men det finns också ett antal nackdelar med tekniken som kunder borde vara uppmärksam på. I denna rapport är fokuseringen på hur villkoren och avtalen vid kontaktering med molnleverantörer ser ut, men fokus ligger också på att öka medvetenheten med riskerna vid kontraktering under en lång tidsperiod. Det finns fortfarande många frågetecken som behöver övervägas och analyseras när det gäller molntekniken. Inriktningen på denna rapport är därför kontrakten och designen av dessa ser ut och som leverantörerna oftast skriver ihop till sin egen fördel. Dessa leverantörsfördelar kommer att uppmärksammas i rapporten, dock är fördelarna med molntekniken lätta att upptäcka vid presentationer om tekniken, men kontrakten kan också innebära problem om beroendet på servicen är stor. För det är kontrakten leverantörerna hänvisar till om det skulle uppkomma fel på servicen. Exempelvis säger kontrakten att vid störningar på servicen kan maximalt 50 % av månadsbeloppen en kund betalar varje månad, återbetalas till kunden. Detta kan vid långvarit störning innebära finansiella problem för kunden. Kontrakt-aspekterna integritet, prestanda och kontrakts ändringar är oftast till fördel för leverantören, men det finns även ytterligare aspekter att försöka förhandla sig till bättre villkor på. Dock finns det åtgärder kunder kan göra för att förbättra sitt kontrakt. Exempelvis kan företag arbeta tillsammans för att stärka inflytandet mot leverantören för att på det sättet kunna förhandla sig till bättre kontraktsdetaljer. / This report highlights the aspects for customers to be aware of before contracting with a cloud provider. Cloud technology is efficient, effective, scalable and easy to implement, but there is also drawbacks that customers or potentials customers should know before contracting. The focus area in this report are the terms and agreements aspects when working with a cloud provider, but the report also highlights the risks with contracting with cloud providers in the long term. The focus is also on the design of the contracts that the providers want to design for their own winning. The report wants to make the reader aware of these pitfalls. There are several benefits with Cloud Computing and information about the technology is easy to find, but the information about the contracts are kept in the shadows and written in small letters by high paid lawyers. With maximum 50% payback of the monthly paid by the customer to the provider, if there is service disruption, the contracts can be an economical nightmare for the customers. With aspects such as privacy, performance and contract changes details that are in favor for the provider, are many aspects to consider when reading and negotiating about a contract. But there are things the costumers can do to improve their contract. An example is that by working together with other companies when the procurement is underway, the leverage is strengthened against the providers to negotiate for better contract details.

The assurance of Quality of Service (QoS) to the applications, although identified as a key feature since long ago [1], is one of the fundamental challenges that remain unsolved. In the Cloud Computing context, Quality of Service is defined as the measure of the compliance of certain user requirement in the delivery of a cloud resource, such as CPU or memory load for a virtual machine, or more abstract and higher level concepts such as response time or availability. Several research groups, both from academia and industry, have started working on describing the QoS levels that define the conditions under which the service need to be delivered, as well as on developing the necessary means to effectively manage and evaluate the state of these conditions. [2] propose Service Level Agreements (SLAs) as the vehicle for the definition of QoS guarantees, and the provision and management of resources. A Service Level Agreement (SLA) is a formal contract between providers and consumers, which defines the quality of service, the obligations and the guarantees in the delivery of a specific good. In the context of Cloud computing, SLAs are considered to be machine readable documents, which are automatically managed by the provider's platform. SLAs need to be dynamically adapted to the variable conditions of resources and applications. In a multilayer architecture, different parts of an SLA may refer to different resources. SLAs may therefore express complex relationship between entities in a changing environment, and be applied to resource selection to implement intelligent scheduling algorithms. Therefore SLAs are widely regarded as a key feature for the future development of Cloud platforms. However, the application of SLAs for Grid and Cloud systems has many open research lines. One of these challenges, the modeling of the landscape, lies at the core of the objectives of the Ph. D. Thesis. / García García, A. (2014). SLA-Driven Cloud Computing Domain Representation and Management [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/36579

No / Aims and This analysis paper describes a comparative evaluation of service deliverables within the Service Level Agreements (SLA) of two acute psychiatric services; one inclusive and the other exclusive of occupational therapy. Methods: Six SLA agreements provided the standards by which the two services were evaluated. The SLAs were evaluated because they are used by the service managers and commissioners to measure performance and clinical effectiveness. The role of the occupational therapists and their contribution to the planning and delivery of the performance indicators is also considered. An evaluation framework was applied to explore the potential role occupational therapy may have had in any performance difference between the two sites. In doing so it is hoped to provide some evidence to support and inform occupational therapists and service managers on the role and of occupational therapy in acute mental health services. This comparative evaluation followed the first three of the five audit stages: 1. Preparing for audit; 2. Selecting criteria; and 3. Measuring performance level. Findings: The service with occupational therapy performed better on home leave day use, ward occupancy and less than 3-day admissions. Conclusions: By delivering their key roles of individual assessment, therapeutic groups, individual treatment and discharge planning occupational therapist were able to contribute to the overall efficiency of service delivery. These findings support the role of the occupational therapist in an acute psychiatric setting and provide guidance for managers on how to utilise occupational therapy in the delivery of service outcomes.