According to the National Institute of Standards and Technology, cloud computing has 5 essential characteristics: On demand / self service All you need to access cloud computing is a device with a browser, an internet connection, and a username and password to your service of choice. Interacting with sales representatives is rarely required. Managing a full IT infrastructure is no longer a pre-requisite. For businesses, capital expenditure and time to market are greatly reduced. Broad network access Cloud computing is accessible from a network. This will mostly be over the internet. In the case of private cloud-based services, the device can be located anywhere within the enterprise. Resource pooling Cloud service providers use a multi-tenant model where, through virtualization, a single server can safely host multiple clients simultaneously. This process is known as resource pooling. Rapid elasticity Rapid elasticity is the cloud computing term for scalable provisioning, which is the ability to provide scalable services. Cloud computing users can automatically request additional space, a provisioning that can seem seamless to the end user, in their services. Like resource pooling, this is done through virtualization. Measured service The billing process is transparent. Each customer pays only for the resources they have used.