Abstract: Like most entrepreneurs, data center operators pursue goals such as profit-maximization, improvement of the company’s reputation or basically to exist on the market. Part of those aims is to guarantee a given quality of service. Quality characteristics are specified in a contract called the service level agreement. Central part of this agreement is non-functional properties of an IT service. The system availability is one of the most important properties as it will be shown in this paper. To comply with availability requirements, data center operators can use virtualization technologies. A clear model to assess the effect of virtualization functions on the parts of a data center in relation to the system availability is still missing. This paper aims to introduce a basic model that shows these connections, and consider if the identified effects are positive or negative. Thus, this work also points out possible disadvantages of the technology. In consequence, the paper shows opportunities as well as risks of data center virtualization in relation to system availability.
Abstract: In this corporate world, the technology of Web
services has grown rapidly and its significance for the development
of web based applications gradually rises over time. The success of
Business to Business integration rely on finding novel partners and
their services in a global business environment. However, the
selection of the most suitable Web service from the list of services
with the identical functionality is more vital. The satisfaction level of
the customer and the provider’s reputation of the Web service are
primarily depending on the range it reaches the customer’s
requirements. In most cases, the customer of the Web service feels
that he is spending for the service which is undelivered. This is
because the customer always thinks that the real functionality of the
web service is not reached. This will lead to change of the service
frequently. In this paper, a framework is proposed to evaluate the
Quality of Service (QoS) and its cost that makes the optimal
correlation between each other. In addition, this research work
proposes some management decision against the functional deviancy
of the web service that is guaranteed at time of selection.