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.

A Reference Architecture for Multi-Level SLA Management

Abstract: Service-orientation is the core paradigm for organising business interactions and modern IT architectures. At the business level, service industries are becoming the dominating sector in which solutions are flexibly composed out of networked services. At the IT level, the paradigms of Service-Oriented Architecture and cloud computing realise service-orientation for both software and infrastructure services. Service composition across different layers is a major advantage of this paradigm. Service Level Agreements (SLAs) are a common approach to specifying the exact conditions under which services are to be delivered, and thus are a prerequisite for supporting the flexible trading of services. However, typical SLAs are only specified at a single layer and do not provide insight into metrics or parameters at the various lower layers of the service stack. Thus they do not allow service providers to manage their service stack optimally. In this chapter, we present a reference architecture for a multi-level SLA management framework. We discuss fundamental concepts of the framework and detail its main architectural components and interactions.

Virtual private networks: joint resource allocation and routing design

Abstract: We consider the resource allocation problem in the design of intranets or virtual private networks (VPNs) that is faced by a service provider, which has service level agreements with various customers to carry their multiservice traffic. The design allocates bandwidth on each link to the VPNs such that, when the traffic of a customer is optimally routed over its VPN, a weighted aggregate measure of carried bandwidth over the service provider's infrastructure is maximized, subject to constraints that each VPN carries a specified minimum. Multiplexing is across services and routes within each VPN, but not across VPNs. The traffic modelling is at the flow or call level, with random arrivals and holding times of calls and each call requiring (effective) bandwidth, which is characteristic of the call's service type, on all links in its route. The network is modelled as a multirate loss network. Scalability of the design process, i.e., the ability to handle OC3 and higher rates, is an important contribution, and this is achieved by the systematic use of a refined uniform asymptotic approximation. Our software package VPN DESIGNER incorporates these results. We report on numerical results for problems with up to 8 VPNs on a network with 8 nodes, 24 OC3 links, 5 services and up to 640 routes.

Designing for resilience

Abstract: The motivation for this work comes from a desire to improve resilience of mission critical cyber enabled systems including those used in critical infrastructure domains such as cyber, power, water, fuel, financial, healthcare, agriculture, and manufacturing. Resilience can be defined as the ability of a system to persistently meet its performance requirements despite the occurrence of adverse events. Characterizing the resilience of a system requires a clear definition of the performance requirements of the system of interest and an ability to quantify the impact on performance by the adverse events of concern. A quantitative characterization of system resilience allows the resilience requirements to be included in the system design criteria. Resilience requirements of a system are derived from the service level agreements (SLAs), measures of effectiveness (MOEs), and measures of performance (MOPs) of the services or missions supported by the system. This paper describes a methodology for designing resilient systems. The components of the methodology include resilience characterization for threat models associated with various exposure modes, requirements mapping, subsystem ranking based on criticality, and selective implementation of mitigations to improve system resilience to a desired level.

Implementing service excellence in higher education

Abstract: Purpose – The purpose of this paper is to provide a critical analysis of the importance of service excellence in higher education.Design/methodology/approach – The research upon which this paper is based employed a phenomenological approach. This method was selected for its focus on respondent perceptions and experiences. Both structured and semi‐structured interviews were conducted to collect relevant data on service excellence. The focus of the research study was on achieving and implementing service excellence in higher education. Findings are analysed and results are grounded in relevant theories and the principle of service excellence.Findings – Preliminary results suggest that implementing service excellence establishes a direct link between a workforce and successful competitive strategies. In order to compete efficiently and effectively in their niche market, higher education institutions need to implement service excellence to ensure both internal and external customer satisfaction. A strong inst...