Systems, Services, Solutions of the Public Cloud

Background

A common view of the cloud is that it is nothing new, that people have been using centralized computing in the form of mainframes for instance. While this sheds light on some of the similarities between mainframes and the cloud, it does not reflect the differences between them, differences that are significant. One useful analogy is to compare the cloud and earlier technologies, with the smart phone and the traditional telephone. While the telephone as such is not new and the smart phone can do the same kinds of things as the traditional phone, it is much more flexible and powerful, and this is down to, in large part, how mobile devices take advantage of the cloud, making them more functional and helping extend battery life (Liu, Chen, Ma, & Xie, 2016). As a term “cloud computing” is problematic because it does not mean one thing, but is “an umbrella term” (Missbach, Stelzel, Gardiner, Anderson & Tempes 2013) that refers not just to a set of technologies but a new model of delivering a wide range of computing resources, services and solutions.

Fortunately, the National Institute of Standards and Technology (NIST) has made a deliberate effort to define cloud computing and done this well, so much so that its three-page description of this term is now considered the standard for the industry. NIST defines cloud computing as “a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction” (Mell & Grance, 2011). This definition is comparable to the four key characteristics of cloud computing as “pay-per-use”, “elastic capacity and the illusion of infinite resources”, a “self-service interface” and “resources that are abstracted or virtualised” (Voorsluys, Broberg, & Buyya, 2011). The cloud is “ubiquitous”, “convenient”, and “on-demand” in the sense that users can access applications and data from anywhere and at any time, and because organizations (or “customers” as the literature often calls them) can, without having to talk to anyone, provision computing resources and services from a “shared pool of configurable computing resources,” a business model that involves renting multi-tenanted infrastructure.