Cloud computing
Cloud computing provides the IT infrastructure and environment to develop/host/run services and applications on demand, with pay-as-you-go pricing, as a resilient service. It also provides resources to store data. The services can in turn be scaled up and down to meet a customer's variable operational needs, ensuring maximum cost efficiency.
There are three primary cloud service delivery models:
Saas (software as a service)
Software as a service refers to software or applications that are accessed over the internet (typically from a public cloud, multi-tenancy (or shared) environment). Unlike desktop applications, Saas apps require no installation as they connect via the internet. Microsoft Office 365 is a popular example.
Iaas (infrastructure as a service)
Infrastructure as a service delivers computing infrastructure – such as CPU, RAM, storage and processors as virtual servers, along with networking capabilities – to provide a hosted data centre on demand upon which businesses can run their applications. This is computing as a service, rather than businesses having to purchase and manage their own expensive infrastructure. As with most cloud services it can be scaled up and down and customers usually only pay for what they consume.
Paas (platform as a service)
Paas refers to the environment within which developers can build and launch new applications. Well known cloud platforms include Microsoft Azure and Amazon EC2 and Force.com.
Typically organisations will use more than one cloud deployment type depending on their needs. The most common deployment types are:
Public cloud
Public clouds are intended to be used by multiple parties at once and are designed to provide maximum value for money through a standardised and hi-scale approach. Many public clouds operate internationally for scale or geographic resilience, but this gives rise to some concerns for some businesses over where their data is being stored at any given time.
Private cloud
Private clouds are intended to be restricted to a single customer or trusted community. These are popular among organisations looking to access the benefits of cloud computing but retain higher control and flexibility of configuration compared with a public cloud. Private clouds can be run inside a company data centre or hosted by a third party. This is an ideal solution where data sovereignty is a key issue.
Hybrid cloud
A hybrid cloud, as the name infers, is a cloud capability that joins either on-premise infrastructure to private or public clouds, or clouds to each other, to provide a customer with a bespoke environment to meet their specific operational needs.
