There are numerous cloud computing solutions that can overwhelm you. While this can be a very vast topic if we delve into the specific details, let us stick to the basics. Primarily, there are three major types of cloud computing which are broadly classified as:
- Infrastructure as a Service (IaaS)
- Platform as a Service (PaaS)
- Software as a Service (SaaS)
There are different ways to integrate these technologies into your business, depending on your needs.
Infrastructure as a Service (IaaS)
In cloud computing terminology, Infrastructure as a Service (IaaS) is the most basic level of hierarchy. Everything other service is built on top it.
An IaaS provider offers pre-installed hardware through a virtualized interface or Hyper V. It generally includes fundamentals like dedicated hardware, virtual machines, and storage. As OS can be built only on top of fundamental hardware, they are not included in IaaS.
With IaaS, you are responsible to install and maintain an OS on top of the basic infrastructure. After installing an OS, you can install the applications and services required on that OS once again.
To sum it up succinctly, IaaS is the base on which other technologies like SaaS and other cloud services are built upon.
Examples of IaaS: Azure stack, Rackspace, Google Compute Engine
Analogy for understanding IaaS:
Consider an example of building a hotel. IaaS would be like getting a hotel site with the building foundation built out, roads and utilities to the site in working condition, and all building materials (steel, beams, columns, cement, doors, windows, elevators, doors, pipes, electrical cables) laid out in silos to purchase and implement in construction. This material is made available to you at a price. You can use specialized labor to build a hotel.
Similarly, the basic infrastructure such as VM, storage, server, network is made available to you from an IaaS provider. You would need system architects and administrators to put all the pieces together and install software licenses.
Platform as a Service (PaaS)
Platform as a Service (PaaS) goes one step beyond IaaS which includes operating environment like Operating System and application services. Thus, we can say that the platforms (i.e. operating systems) which are built on top of the basic hardware i.e. infrastructure can be categorized under PaaS.
Platforms like operating systems, databases, web servers, execution environments can be included in PaaS.
IaaS and PaaS are closely intertwined together. Organizations committed to a specific development environment for a certain application without managing the deployment themselves opt for PaaS.
Examples of PaaS: Azure Apps, AWS Elastic Beanstalk, Heroku, Apache Stratos, Google App Engine
Analogy for understanding PaaS:
Let’s take our hotel construction example. PaaS is like getting a ready-made hotel building, with utilities, elevators, floors, and rooms. You have a ready-to-go hotel that can be operational with minimum changes. You also have the choice to customize your hotel the way you want. Design and add furniture, electronics, sheets, towels, and decorations to suit your requirement. This provides a platform for you to complete the hotel, so that guests can use the hotel.
Similarly, PaaS comes with pre-built platform that may include pre-installed OS and services which you can populate with your data and applications. You have less requirement of system architects, but you still need system administrators.
Software as a Service (SaaS)
The most advanced type of cloud computing, which is also the most widely used, as it offers access to a certain application directly. This saves a lot of hassle that exists in IaaS and PaaS stages.
Being a fully managed solution offered and owned by a third-party vendor like Apps4Rent, SaaS solutions can be directly accessed by the end-users for day-to-day activities. Office 365 falls under the SaaS category as end users can use Microsoft’s solutions like Office on a monthly subscription basis.
Examples of SaaS: Office 365, Google Suite, Dropbox, BigCommerce
Analogy for understanding SaaS:
Once the hotel is constructed, it is only of value when the guests arrive. Similarly, the software/application is required to be put on the platform dealt in the PaaS stage. Software as a Service is like renting a room in a hotel. Just like guests in the hotel don’t worry about how the hotel was built, the end-users of the software don’t care about platform or infrastructure if the service is fine.
Similarly, users can host their applications and services by paying a subscription fee. If their services are hosted fine, they don’t worry about things like platform and infrastructure which are managed by others.
|Components||Managed by IaaS|
|Managed by PaaS|
|Managed by SaaS|
What should you choose?
Selection of right type of cloud computing technology depends on what you require from the technology and your profile as well.
If you are the end consumer who uses software like MS Office, emails, social networks – SaaS is perfect for you as it is primarily suited for the end-users.
If you are into development who doesn’t want to manage infrastructure – PaaS is suitable as you want to focus on developing the application without bothering about the management of the platform.
If you have a complicated IT implementation that you are migrating to the Cloud – IaaS may be the right solution for you as it involves the development of infra right from scratch.