Cloud computing boasts several attractive benefits for businesses and end users. Three of the main benefits of cloud computing are:
User self-provisioning, also known as cloud self-service, is a system that allows end users to set up and launch applications and services in a cloud computing environment without the direct intervention of an IT organization or a service provider. User self-provisioning can be used in public, private and hybrid cloud scenarios.
In many public clouds, user self-provisioning can take place over the Internet using web applications or services provided by a third-party provider partnering with the cloud provider, or the cloud provider may have its own back-end system for self-provisioning. In many enterprises, an IT organization will establish a portal application that business unit leaders and end users can use to request the resources necessary to run a new application.
Many self-provisioning user portals are paired with a service catalog, which is a list of applications and services that are sanctioned by an enterprise’s IT organization and available for self-provisioning. The IT organization can establish several back-end policies that automatically assign compute, storage and network resources to support the applications in a service catalog, along with specific security and performance settings.
Many cloud providers, particularly those that cater to smaller businesses, provide their own user self-provisioning portals to customers. Many leading providers of Software-as-a-Service (SaaS), such as Salesforce.com, provide customer portals that allow user self-provisioning. If an IT organization wants to be the gatekeeper of cloud resources consumed by an enterprise, it can set up its own internal self-provisioning portals.
Elasticity is the ability of an IT infrastructure to quickly expand or cut back capacity and services without hindering or jeopardizing the infrastructure's stability, performance, security, governance or compliance protocols.
Although the words scalability and elasticity are sometimes used as synonyms, scalability is more often used to describe the ability a system has to successfully cope with an expanding workload, while elasticity implies that the system is also capable of decommissioning capacity or resources when they are no longer needed.
In this sense, elasticity is a synonym for adaptability. Attributes of an elastic IT environment include the environment's ability to expand and contract in response to business needs. In a cloud service environment, elasticity may also imply that the ability the service can expand and contract in real time, using service level agreements (SLAs) to make changes autonomically, instead of relying on human administrators.
Customers for cloud services that are described as being elastic pay only for the capacity and resources they use.
Metered services (also called pay-per-use) is any type of payment structure in which a customer has access to potentially unlimited resources but only pays for what they actually use. Metered services are becoming increasingly common in enterprise information technology (IT) environments. With utility computing, for example, a company can purchase computing resources to match fluctuating needs. This approach is promoted as being more cost-effective for the company than maintaining a large infrastructure that exceeds the company's average computing power requirements.
Metered services are also gaining popularity in the consumer market. Some Internet service providers (ISPs) have begun to charge customers according to usage instead of charging a flat monthly subscription fee. A growing number of entertainment Web sites also use a pay-per-use structure. Apple Computer's iTunes, for instance, allows users to sample over 2,000 music sample files for free, but charges the user a small fee for a complete download of any given song.