Cloud computing, also mentioned as “the cloud,” is that the delivery of on-demand computing
resources—everything from applications to data centers—over the web on a pay-for-use
To get a standard understanding of cloud computing, let’s start with the US National Institute
of Standards and Technology (NIST’s) definition of cloud computing.
NIST defines cloud computing as a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources which will be rapidly provisioned and released with minimal management effort or service provider interaction.
Examples of computing resources include networks, servers, storage, applications, and services.
This cloud model is composed of five essential characteristics of Cloud Computing, three deployment models, and three service models.
Let’s start with understanding the five essential characteristics of the cloud—which include on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service.
5 Essential Characteristics of Cloud Computing:
On-demand Self-service, the 1st characteristic, means that you get access to cloud resources such as the processing power, storage, and network you need, using a simple interface, without requiring human interaction with each service provider.
The 2nd characteristic, Broad Network Access, means cloud computing resources are often
accessed via the network through standard mechanisms and platforms like mobile phones,
tablets, laptops, and workstations.
The 3rd characteristic, Resource Pooling, is what gives cloud providers economies of
scale, which they pass on to their customers, making cloud cost-efficient.
Using a multi-tenant model, computing resources are pooled to serve multiple consumers; cloud resources are dynamically assigned and reassigned, consistent with demand, without customers needing to concern themselves with the physical location of these resources.
Rapid Elasticity, the 4th characteristic, implies that you simply can access more resources
when you need them and reduce once you don’t—because resources are elastically
provisioned and released.
And the 5th characteristic, Measured Service, means you simply buy what you employ or
reserve as you go; if you’re not using resources, you’re not paying.
Resource usage is monitored, measured, and reported transparently supported utilization.
As we see, cloud computing is basically about utilizing technology “as a service”—leveraging
remote systems on-demand over the open internet, scaling up and scaling back, and paying for what you use.
It is a revolution therein it’s changed the way the planet consumes compute services
by making them more cost-efficient while also making organizations more agile in responding
to changes in their markets.
We just went over the five essential characteristics of Cloud Computing
While we will go into greater depth of the deployment and the service models in the later
videos, let me leave you with a quick overview of those models.
There are three sorts of cloud deployment models—
Public cloud is once you leverage cloud services over the open internet on hardware owned by the cloud provider, but its usage is shared by other companies.
Private cloud means the cloud infrastructure is provisioned for exclusive use by one organization. It could run on-premises or it might be owned, managed, and operated by a service provider. And once you use a mixture of both public and personal clouds, working together seamlessly,
that is classified as the Hybrid model.
Now, let’s check out the three service models that are supported the three layers during a computing stack – Infrastructure, Platform, and Applications.
These cloud computing models are aptly mentioned as Infrastructure as a Service (Iaas),
Platform as a Service (PaaS), and Software as a Service (SaaS).
In an Infrastructure as a Service model, you get access to infrastructure and physical
computing resources such as servers, networking, storage, and data center space – without the need to manage or operate them.
In a Platform as a Service model, you get access to the platform, that’s the hardware
and software tools, usually those needed to develop and deploy applications to users over
Software as a Service may be a software licensing and delivery model during which software and applications are centrally hosted and licensed on a subscription basis, and sometimes also mentioned as “on-demand software.”