Service level

About: Service level is a research topic. Over the lifetime, 7647 publications have been published within this topic receiving 126093 citations. The topic is also known as: service level.

Pricing and Service Level Decisions under a Sharing Product and Consumers’ Variety-Seeking Behavior

Abstract: We developed a two-period duopoly model to show how consumers’ variety-seeking behavior affects the pricing and service level decisions of a traditional product and a sharing product. Our analysis revealed that, without considering the consumers’ variety-seeking behavior, the traditional product attracted consumers with a high level of service and high price, while the sharing product attracted consumers with a low level of service and low price. When we only considered variety-seeking behavior and did not adjust the service level, the product with the low level of service benefited from the consumers’ variety-seeking behavior, while the product with the high level of service lost profits. When we considered the variety-seeking behavior and adjusted the service level as well as the price, the sharing product was attractive to variety-seeking consumers and it gained a greater competitive advantage over the traditional product. For two periods, the number of variety-seeking consumers who switched from buying traditional products to buying sharing products was greater than those who switched from buying sharing products to buying traditional products. Furthermore, we found that when the consumers’ variety-seeking behavior was not obvious, the number of consumers shifting from the traditional product increased monotonically. In contrast, when the variety-seeking behavior was obvious, the number of consumers shifting from the traditional product decreased monotonically.

Performance monitoring of service-level agreements for utility computing using the event calculus

Abstract: Utility computing (UC) is concerned with the provisioning of computational resources (compute-power, storage, network bandwidth), on a per-need basis, to corporate businesses. Service-level agreements (SLAs) - contracts between a provider and a customer - are a sine qua non in the deployment of UC. A crucial stage in the life-cycle of contracts (such as SLAs) is their automated performance monitoring while active; a significant aspect of which concerns the tracking of contract state. In this work, we define an ontology to capture aspects of SLAs that are pertinent to the tracking of state for performance monitoring, and generalise these aspects so that the ontology may be applicable to other contract domains. The ontology is formalised as an XML-based language, called CTXML (contract tracking XML). The semantics for CTXML are presented in terms of a computational model based on the event calculus.

Automatic SLA Matching and Provider Selection in Grid and Cloud Computing Markets

Abstract: Cloud computing is a novel computing paradigm that offers data, software, and hardware services in a manner similar to traditional utilities such as water, electricity, and telephony. Usually, in Cloud and Grid computing, contracts between traders are established using Service Level Agreements (SLAs), which include objectives of service usage. However, due to the rapidly growing number of service offerings and the lack of a standard for their specification, manual service selection is a costly task, preventing the successful implementation of ubiquitous computing on demand. In order to counteract these issues, automatic methods for matching SLAs are necessary. In this paper, we introduce a method for finding semantically equal SLA elements from differing SLAs by utilizing several machine learning algorithms. Moreover, we utilize this method to enable automatic selection of optimal service offerings for Cloud and Grid users. Finally, we introduce a framework for automatic SLA management, present a simulation-based evaluation, and demonstrate several significant benefits of our approach for Cloud and Grid users.

A SLA framework for QoS provisioning and dynamic capacity allocation

Abstract: Any QoS scheme must be designed from the perspective of pricing policies and service level agreements (SLAs). Although there has been enormous amount of research in designing mechanisms for delivering QoS, its applications has been limited due to the missing link between QoS, SLA and pricing. Therefore the pricing policies in practice are very simplistic (fixed price per unit capacity with fixed capacity allocation or pricing based on peak or 95-percentile load etc.). The corresponding SLAs also provide very limited QoS options. This leads to provisioning based on peak load, under-utilization of resources and high costs. We present a SLA based framework for QoS provisioning and dynamic capacity allocation. The proposed SLA allows users to buy a long term capacity at a pre-specified price. However, the user may dynamically change the capacity allocation based on the instantaneous demand. We propose a three tier pricing model with penalties (TTPP) SLA that gives incentives to the users to relinquish unused capacities and acquire more capacity as needed. This work may be viewed as a pragmatic first step towards a more dynamic pricing scenario. We solve the admission control problem arising in this scheme using the concept of trunk reservation. We also show how the SLA can be used in virtual leased-line service for VPNs, and Web hosting service by application service providers (ASPs). Using Web traces we demonstrate the proposed SLA can lead to more efficient usage of network capacity by a factor of 1.5 to 2. We show how this translates to payoffs to the user and the service provider.

Provisioning for large scale cloud computing services

Abstract: Resource provisioning, the task of planning sufficient amounts of resources to meet service level agreements, has become an important management task in emerging cloud computing services. In this paper, we present a stochastic modeling approach to guide the resource provisioning task for future service clouds as the demand grows large. We focus on on-demand services and consider service availability as the key quality of service constraint. A specific scenario under consideration is when resources can be measured in base instances. We develop an asymptotic provisioning methodology that utilizes tight performance bounds for the Erlang loss system to determine the minimum capacity levels that meet the service availability requirements. We show that our provisioning solutions are not only asymptotically exact but also provide better QoS guarantees at all load conditions.