There are five essential characteristics of Cloud Computing which define the underlying service standard. 

 

Characteristics

 

On-Demand Self-Service -- A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service’s provider.

 

Broad Network Access -- Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms.

 

Resource Pooling -- The provider’s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. There is a sense of location independence in that the customer generally has no control or knowledge over the exact location of the provided resources but may be able to specify location at a higher level of abstraction.

 

Rapid Elasticity -- Capabilities can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time.

 

Measured Service -- Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service. Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service.

 

Deployment Models

 

Based on these characteristics, there are five deployment models that can be mixed and matched to accommodate the service levels stipulated for your systems, predominantly as it relates to performance and availability.

 

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.

 

Private (Internal) 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.

 

Enterprise Cloud – The cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns. It may be managed by the organizations or a third party and may exist on premise or off premise.

 

Hybrid (Federated) Cloud – The cloud infrastructure is a composition of two or more clouds that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability.

 

Virtual Private Cloud – a cloud service that simulate a private cloud inside a public cloud infrastructure.