Cloud Basics

What is cloud computing?

Cloud computing has evolved from a risky and confusing concept to a strategy that organizations large and small are beginning to adopt as part of their overall computing strategy. Companies are now starting to ask not whether they should think about cloud computing but what types of cloud computing models are best suited to solve their business problems. 

There are many important cloud fundamental services —

• Infrastructure as a Service (IaaS) and Platform as a Service (PaaS) — to develop and deploy applications to support the business and open up new innovative opportunities and new revenue streams.
• Software as a Service (SaaS) provides packaged business process offerings that live in cloud and leverage both IaaS and PaaS services.

While cloud computing and services can be use for some relatively simple purposes also. like -

• e-mail
• Customer relationship management

Cloud computing is a method of providing a set of shared computing resources that includes - 

• Applications
• Computing
• Storage
• Networking
• Development
• Deployment platforms
• Business processes

Cloud computing turns traditional and typical computing assets into shared pools of resources that are based on an underlying Internet foundation.

Clouds come in different versions, depending on your needs. There are two primary deployment models of cloud -

• Public
• Private

Most organizations use a combination of private computing resources (data centers and private clouds) and public services as a hybrid environment.

The cloud doesn't exist in isolation to other corporate IT investments. The reality is that most companies use a combination of public and private cloud services in conjunction with their data center. Companies use different methods, depending on their business requirements to link and integrate these services. The way you construct your hybrid computing environment is determined by complexity of workloads and how you want to optimize performance of those workloads to support your constituents.

We may consider following factors for deciding deployment kind for cloud -

• Particular performance
• Security requirements
• Specific business goals

IaaS- 

The delivery of services such as hardware, software, storage, networking, data center space, and various utility software elements on request. Both public and private versions of IaaS exist.

In a public IaaS, user needs a simple sign-up mechanism to acquire resources. When users no longer need the resources, they can de-provision them.

In a private IaaS, IT organization or an integrator creates an infrastructure designed to provide resources on demand to internal users and sometimes partners. IaaS is the fundamental element used by other cloud models. Some customers bring their own tools and software to create applications.

PaaS- 

A mechanism for combining IaaS with an abstracted set of middle-ware services, software development and deployment tools that allow the organization to have a consistent way to create and deploy applications on a cloud or on-premises environment. A PaaS environment supports coordination between the developer and the operations organization, typically called DevOps. A PaaS offers a consistent set of programming and middleware services that ensure developers have a well-tested and well-integrated way to create applications in a cloud environment. A PaaS requires an infrastructure service.

SaaS- 

A business application created and hosted by a provider in a Multi-Tenant (shared) model. The SaaS application sits on top of both a PaaS and foundational IaaS. A SaaS environment can be built directly on an IaaS platform. Typically these underlying services aren’t visible to end-users of a SaaS application.

Cloud Capabilities -

• Elasticity and self-service provisioning
• Billing and metering of service usage
• Workload management
• Management services