Cloud computing is the delivery of computing services like servers, storage, databases, networking, software, analytics and more—using the Internet (“the cloud”).
Companies offering these services are called cloud service providers and typically charge for cloud computing services based on usage.
These companies have highly optimized data centers that provide software resources and hardware resources for use.
In order expand technology based companies have to invest in there IT infrastructure.
To avoid investing heavily on in house IT resources these companies can use facilities provided by these providers.
Organizations have to simply connect to the cloud and use various resources on pay per use basis. This helps companies from scales up and scale down easily.
Service Models of Cloud Computing :
The most basic category of cloud computing services. With IaaS, companies rent IT infrastructure—servers and virtual machines (VMs), storage, networks —from a cloud provider on a pay-as-you-go basis.Its like you are given a computer without even having OS on it. Amazon Web Services (AWS), DigitalOcean, Linode, Rackspace,Microsoft Azure, Google Compute Engine (GCE) are some examples of Iaas.
Software as a Service(SaaS):
SaaS is a method of delivering software services over the Internet. In SaaS cloud service providers host and manage the application.
These services are available to multiple users at a time.
Users connect to the application using their web browser or lightweight client side application.
Example of SaaS providers are Google Docs, Gmail, Microsoft office 360.
Platform as a Service(PaaS):
PaaS provide computing platform for programming language execution environment. An OS, web server and a DB.
This model provides facility to deploy or host applications over the cloud without worrying
About managing the underlying infrastructure of server , storage databases.
Users access PaaS through web browser. PAAS providers charge for that access on per user basis.
Popular PaaS platform include Amazon Web Services , Google App Engine , Microsoft Azure.
• Cost Effective , Rapid Development.
• Easy Deployments.
Cloud Deployment Models:
There are three types of Cloud Deployment Models –
Public Cloud :
Public Cloud is publicly accessible cloud environment owned and managed my cloud service providing companies.
Some examples of public cloud includes –
Online software applications
Cloud storage services
Cloud hosting, including website hosting
Cloud based development environments
Features of Public Cloud:
Scalability : Because cloud resources are available on demand from the public cloud’s
vast pool of resources, applications running in those clouds can be scaled easily or automatically to run seamless in case of sudden increase or decrease in traffic on a web application.
Reliability : The number of servers and networks involved in creating public clouds and multiple copies of a application is maintained by these Cloud Service Providers , even if one physical component fails, the cloud service runs without being affected by the remaining components.
In the private cloud model, clouds (pool of resources) can only be accessed by a single organization, thus providing greater control and privacy to the organization.
Like other cloud models, private clouds provide computing power as a service within a virtual environment, using pools that underlie physical computing resources.
Hybrid cloud is the combination of one or more public cloud providers (such as Amazon Web Services or Google Cloud Platform) with a private cloud platform — one that’s designed for use by a single organization — or private IT infrastructure. The public cloud and private infrastructure, which operate independently of each other, communicate over an encrypted connection, using technology that allows for the portability of data and applications.
In a hybrid cloud arrangement the public and private clouds are distinct and independent things.
This enables organizations to store protected or sensitive data on a private cloud, while retaining the ability to leverage computational resources from the public cloud to run applications that rely on this data. This keeps data exposure to a bare minimum because they’re not storing sensitive data long-term on the public cloud.