Cloud computing is the delivery of computing services over the internet rather than having local servers or personal devices handle applications. Computing services can include servers, storage, databases, networking, software, analytics, and intelligence. These services are moved outside an organization’s firewall and can be accessed via the web. Cloud computing lowers operating costs and allows for efficient scaling as customers pay on an as-needed or pay-per-use business model.
Characteristics of cloud computing
According to the National Institute of Standards and Technology (NIST), all true cloud environments have five key characteristics:
- On-demand self-service: Cloud customers can quickly sign up, pay for, and start using cloud resources on their own without help from a sales agent.
- Broad network access: Customers access cloud services via the internet.
- Resource pooling: Different types of customers (individuals, organizations, or different departments within an organization) all use the same servers, storage, or other computing resources.
- Rapid elasticity or expansion: Cloud customers can easily scale their use of resources up or down as their needs change.
- Measured service: Customers pay for the amount of resources they use in a given period of time rather than paying for hardware or software upfront. (Note that in a private cloud, this measured service usually involves some form of chargebacks where IT keeps track of how many resources different departments within an organization are using.)
Types of cloud computing
Not all clouds are the same. Cloud computing is divided into subcategories depending on the physical location of computing resources and who can access those resources.
Public clouds are owned and operated by a third-party cloud service provider who offers services to the general public. With a public cloud, all hardware, software, and other supporting infrastructure is owned and managed by the cloud provider. These services are accessed and managed using a web browser.
A private cloud is a cloud environment used exclusively by one organization and can be physically located on the organization’s on-site data center. Large enterprises typically choose to keep their data and applications in a private cloud for security reasons. In other cases, private clouds are used in order to comply with company regulations.
Organizations have two options when using a private cloud: it can be set up in the organization’s own data center, or a hosted private cloud service can be used. With a hosted private cloud, a public cloud vendor agrees to set aside computing resources and allow only one customer to use those resources.
A hybrid cloud is a combination of public and private clouds bound together by the technology that allows data and applications to be shared between them. Companies choose hybrid cloud computing for greater flexibility, increased deployment options, and optimized infrastructure, security, and compliance.
Cloud service models
Cloud services are typically deployed based on the end-user (business) requirements. Primary services include:
Infrastructure as a Service (IaaS)
Iaas is the most basic category of cloud computing services. Computer infrastructure such as servers, storage, and networking are delivered as a service. Iaas is popular among enterprises because of the convenience of having the cloud vendor manage their IT infrastructure. Popular Iaas providers include Amazon Web Services, Microsoft Azure, and IBM.
Platform as a Service (PaaS)
PaaS is a computing platform that is delivered as a service. The platform is outsourced in place of a company or data center buying and managing its own hardware and software layers. It provides an on-demand environment for developing, testing, delivering, and managing software applications. PaaS is designed for developers to create and deploy software. Popular PaaS vendors include Amazon Web Services, Microsoft Azure, IBM
Software as a Service (SaaS)
Saas is a software delivery method that provides access to software and its functions remotely as a web-based service. With SaaS, cloud providers host and manage the software application and underlying infrastructure and handle the required maintenance. SaaS customers pay a recurring (often monthly or annual) fee to subscribe to the service. Popular SaaS vendors include Salesforce, Google G Suite, Dropbox, and Adobe Creative Cloud.
Benefits of Cloud Computing
While the reason behind why companies decide to use cloud computing vary, a few remain at the forefront:
- Low costs
- Anytime, anywhere access
- High availability