When you ask an uninitiated person to define the cloud, you usually get an answer along the lines of “accessing your data and apps on the Internet instead of your computer”. But as the cloud becomes more widely adopted, its definition becomes more accurate.
So What is the Cloud?
A cloud offer needs to meet certain criteria. First of all, it must be on-demand, self-serviced and paid based on your usage.
On-demand means the service is available and simple has to be put to use. Usually, in IT, when you need an application, you must figure out where to install it and how to make it available to the users who need it. You could draw a parallel with electricity in our homes, as if, when buying a new device, you would decide to which power plant it should be connected. The electricity we consume is on-demand, because you just plug your device and it works. For IT applications and services, the cloud is not unlike our electric grid. The services are there, just waiting to be tapped into.
Then what qualifies as “the cloud” has to be deliverable via the Internet or, at the very least, via a network. Delivered via the internet usually is the accepted definition, but more and more organizations are deploying private clouds and access them through their local network, without necessarily going through the Internet. And because other criteria are met, I say it qualifies as cloud.
Finally, a cloud service is elastic, meaning that for a light usage, you will be consuming few resources, whereas a more sustained usage will consume more resources.
The Types of Services
Infrastructure as a Service (IaaS)
The Infrastructure as a Service enables organizations to acquire infrastructure resources (ie: CPUs, memory, storage, network, and so on) on an on-demand basis, with usage-based billing, and accessible via their network to benefit from the elasticity of the resources.
Platform as a Service (PaaS)
The Platform as a Service is comprised of what the infrastructure provides, and adds an additional layer of software and service components that enable application development.
Software as a Service (SaaS)
Software as a Service is a cloud-based software owned and operated by a third party. Users access it via the Internet and, often, using a web browser.
A well known example that explains the difference between the three services is the Pizza as a Service analogy.
Cloud Deployment Models
The cloud can be deployed according to three main models: public cloud, private cloud, and hybrid cloud.
What is known as the public cloud is comprised of cloud providers making their infrastructure available to multiple clients. Services used by various organizations are then located on the same equipment, and IT resources are shared among clients.
A private cloud, on the other hand, has its combined resources available for a single organization.
The hybrid cloud, as you may have guessed, is somewhere in between. An organization could have its own private cloud and also use the public cloud for different applications. This is known as a hybrid cloud.
So where to start? What do you need? The first step is to talk with a reliable cloud provider and see what they offer.