Variety of QoS - the MNM Service Model Applied to Web Hosting Services

In today’s IT environments customers often have to rely on best-effort services such as IP and e-mail. In order to have a competitive advantage, service providers offer different kinds of guarantees for their services which are often called Quality of Service (QoS) parameters. Parameters in this sense are service-specific, and are not limited to classical network QoS parameters (e.g. delay, jitter, loss). However, customers and providers still share no common understanding regarding the specification of these parameters. To address this issue we propose a QoS specification process composed of two steps: model the service in question and specify the QoS parameters with respect to the resulting model. In this paper, we identify requirements for an extension of the MNM Service Model in order to support the mentioned specification process. Therefore, we analyze a scenario, the Web Hosting Service offered by the Leibniz Supercomputing Center, to identify typical QoS aspects. We then use the example scenario to gain requirements for an extension of the model for service-oriented QoS parameters.