What Is Cloud Computing?

Cloud computing significantly altered some of the established IT conventions, even though the majority of the underlying technology and security fundamentals remain the same. Many of the key IT principles addressed in this chapter reaffirm the underlying features that remain constant as cloud computing provisioning and consumption models are embraced. The cloud computing Software-as-a-Service (SaaS) model uses internet-based computing resources to provide scalable and elastic IT-enabled capabilities to internal or external consumers.

Various cloud service providers, such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform, have their own definitions of cloud computing, based on their respective service offerings. The non-regulatory agency of the United States Department of Commerce, the National Institute of Standards and Technology (NIST), in its Special Publication (SP) 800-145, provides the most widely used definition for cloud computing, which is cited by IT experts and cloud computing professionals when communicating the basic terminology:

“Cloud computing is 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. This cloud model is composed of five essential characteristics, three service models, and four deployment models.”

Note

You can read about the NIST publication 800-145 cloud computing definition here: https://csrc.nist.gov/publications/detail/sp/800-145/final.

Now that you are familiar with the definition of cloud computing, it is time to focus on the five essential characteristics of cloud computing.