by Brian Sheehan, VP, Network Systems & Support
There’s a lot of buzz about cloud computing, and the reality is that most organizations will be using some form of it in the near future. The question remaining for many organizations is simply: what will my cloud look like? At the crux of this question is understanding the basic definition and purpose of cloud computing, as it has certainly come to mean a lot of different things to a lot of different people.
The following provides an excellent overview of cloud computing. It is excerpted, with permission, from the National Institue of Standards and Technology’s (NIST) Information Technology Laboratory. NIST is a non-regulatory federal agency within the U.S. Department of Commerce that promotes U.S. innovation and industrial competitiveness.
The NIST Definition of Cloud Computing
Authors: Peter Mell and Tim Grance; Version 15, 10-7-09
Definition of Cloud Computing:
Cloud computing is a model for enabling 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 promotes availability and is composed of five essential characteristics, three service models, and four deployment models.
Essential Characteristics:
- On-demand self-service
- Broad network access
- Resource pooling
- Rapid elasticity
- Measured service
Service Models:
Cloud Software as a Service (SaaS). The capability provided to the consumer is to use the provider’s applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface such as a web browser (e.g., web-based email).
Cloud Platform as a Service (PaaS). The capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider.
Cloud Infrastructure as a Service (IaaS). The capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications.
Deployment Models:
Private cloud. The cloud infrastructure is operated solely for an organization. It may be managed by the organization or a third party and may exist on premise or off premise.
Community cloud. The cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be managed by the organizations or a third party and may exist on premise or off premise.
Public cloud. The cloud infrastructure is made available to the general public or a large industry group and is owned by an organization selling cloud services.
Hybrid cloud. The cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting for load-balancing between clouds).