<P> Cloud computing is an information technology (IT) paradigm that enables ubiquitous access to shared pools of configurable system resources and higher - level services that can be rapidly provisioned with minimal management effort, often over the Internet . Cloud computing relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility . </P> <P> Third - party clouds enable organizations to focus on their core businesses instead of expending resources on computer infrastructure and maintenance . Advocates note that cloud computing allows companies to avoid or minimize up - front IT infrastructure costs . Proponents also claim that cloud computing allows enterprises to get their applications up and running faster, with improved manageability and less maintenance, and that it enables IT teams to more rapidly adjust resources to meet fluctuating and unpredictable demand . Cloud providers typically use a "pay - as - you - go" model, which can lead to unexpected operating expenses if administrators are not familiarized with cloud - pricing models . </P>

Which of the following is one of the characteristics of using software as a service model