IaaS (Infrastructure as a service)
It is the widest type. In this case the client is provided with the IT infrastructure and he receives:
* storage
* compute (the vendor provides virtualized CPUs, GPUs, HPCs)
* network resources.
This means that as a customer, instead of buying servers and hardware, you „rent” them from an external provider in a virtual form. The customer uses his programs and applications, which are located on the vendor servers by using their processing power.
As far as payment models are concerned, there are several, but among them the most popular will be the pay-as-you-go model. The user pays for the time of use (hours, weeks, etc.) and/or the place used (for the size of files).
Some of IaaS providers:
Amazon AWS;
DigitalOcean;
Microsoft Azure;
Rackspace Open Cloud;
Google Compute Engine;
HP Enterprise Converged Infrastructure;
IBM SmartCloud Enterprise.
Excel Ribbon contains multiple tabs, each with several groups of commands. You will use these tabs to perform the most common tasks in Excel.
Minimizing or Maximizing the Ribbon – Hold down the CTRL key and press the F1 key.
PaaS (Platform as a Service)
The key word here is : “Platform”. This model is especially aimed at programmers for software development, testing, etc., because the vendor provides tools on which they can work. The vendor take responsibilities for security, software providing and creating backups, and etc..
The vendor provides here the so-called development environment, which can reduce the working time of developers. The tools offered to companies usually include also a business analytics services or monitoring.
PaaS is also ideal for working on a single product by people from different places/time zones, as the environment is accessible via the internet.
PaaS providers:
Oracle Cloud Platform;
Google App Engine;
Microsoft Azure;
Salesforce aPaaS;
Red Hat OpenShift PaaS;
Mendix aPaaS;
SAP Cloud Platform.
SaaS (Software as a Service)
SaaS is the highest level on the pyramid when it comes to cloud models, which means that it requires a basic level of IT skills from the user. It is very common and you probably used it many times without even realizing it. You use Google sheets? You used SaaS. In this case, as a customer, you are provided with everything from the vendor and you don’t have to worry about IT operations. This means that you don’t have to manage the software (you don’t have to install or update it), it’s in the cloud that you can access with your browser or make backups etc. All this work will be done for you by your provider.
As a rule, payments work here in a subscription model (you pay for the service on a monthly basis), some can be free of charge (free in limited functionality).
SaaS providers:
Salesforce;
Microsoft (for example Office 365);
Adobe Creative Cloud;
Box;
Google G Suite;
Slack;
Cisco
Besides these three best-known types, there are a few others, less frequently listed. It is important to remember that you can combine these models with each other.