What Does Cloud Computing Mean?
Cloud computing is a service model that allows information technology (IT) customers to obtain computing resources over the internet. In network diagrams and flowcharts, an icon that resembles a cloud is traditionally used to represent the internet.
A cloud computing environment has five important characteristics that differentiate it from a traditional computing environment:
- Self Service – the customer can provision computing resources by themselves, on demand.
- Network Access – resources are provisioned and accessed over the internet.
- Resource Pools – resources are pooled together to serve the needs of multiple customers.
- Elasticity – resources can be rapidly provisioned or scaled down depending on real-time need.
- Measured Services – resource usage can be monitored and controlled by the customer.
Cloud Deployment Models
Organizations have several choices for deploying a cloud computing models:
- Public Clouds - allow resources to be accessed by authorized subscribers.
- Private Clouds - restrict resource access to a specific group or organization.
- Community Clouds - allow resources to be shared among two or more organizations.
- Hybrid Clouds - resources are provided by at least two cloud service providers.
Cloud Delivery Models
Organizations have several choices for delivering cloud computing:
Software as a Service (SaaS) - SaaS is the form of cloud service that most consumers are familiar with. When SaaS applications are used in business, it tends to reduce the cost of software ownership by removing the need for technical staff to install, manage and maintain software. SaaS applications can be free or purchased through a subscription model. Tier 1 SaaS vendors include Google, Salesforce and Microsoft.
Platform as a Service (PaaS) - The provider manages backend resources for software, including operating systems, middleware and databases. PaaS services are used to improve developer productivity and reduce time-to-market. Tier 1 vendors include Microsoft Azure, Amazon Web Services, Google Cloud, IBM Cloud and Oracle Cloud Infrastructure.
Infrastructure as a Service (IaaS) - IaaS allows customers to virtually build a data center without having to invest in capacity planning or the physical maintenance and management of it. Tier 1 vendors include AWS Elastic Compute Cloud , Google Compute Engine and Alibaba Elastic Compute Service.