Cloud Computing Service Model: SaaS | PaaS | IaaS

Cloud Services are among the most in-demand services recently, with big organizations like Microsoft, Google, Amazon, Oracle driving the path for innovation development. Rather than depending on their own private servers, organizations incline toward contracting out the storage to reputable providers, ignoring the obligation regarding supporting the foundation and guaranteeing security.

Cloud Computing Service Models

There are three main types of cloud computing services. Each type of cloud computing provides different levels of control, flexibility, and management so that you’ll select the proper set of services for your needs. The three Cloud Service Models are as follows:

Infrastructure As A Service (IaaS)

• It is the most flexible type of cloud service which lets you rent the hardware and contains the basic building blocks for cloud and IT.
• It gives complete control over the hardware that runs your application (servers, VMs, storage, networks & operating systems).
• It’s an instant computing infrastructure, provisioned and managed over the internet.
• IaaS gives you the very best level of flexibility and management control over your IT resources.
• It is most almost like the prevailing IT resources with which many IT departments and developers are familiar.
• Examples of IaaS: VM or EC2 (from AWS), Storage or Networking.

Check Out: What is IAM in AWS?

Platform As A Service (PaaS)

• PaaS is a cloud service model that gives a ready-to-use development environment where developers can specialize in writing and executing high-quality code to make customized applications.
• It helps to create an application quickly without managing the underlying infrastructure. For example, when deploying a web application using PaaS, you don’t have to install an operating system, web server, or even system updates. However, you can scale and add new features to your services.
• This cloud service model makes the method of developing and deploying applications simpler and it is more expensive than IaaS but less expensive than SaaS.
• This helps you be more efficient as you don’t get to worry about resource procurement, capacity planning, software maintenance, patching, or any of the opposite undifferentiated work involved in running your application.
• Examples of PaaS: Elastic Beanstalk or Lambda from AWS, WebApps, Functions or Azure SQL DB from Azure, Cloud SQL DB from Google Cloud, or Oracle Database Cloud Service from Oracle Cloud.

Software As A Service (SaaS)

• SaaS provides you with a complete product that is run and managed by the service provider.
• The software is hosted online and made available to customers on a subscription basis or for purchase in this cloud service model.
• With a SaaS offering, you don’t need to worry about how the service is maintained or how the underlying infrastructure is managed. It would help if you believed how you’d use that specific software.
• Examples of SaaS: Microsoft Office 365, Oracle ERP/HCM Cloud, SalesForce, Gmail, or Dropbox.

Read More: About Secret Manager AWS.

Graphical Comparison of Cloud Computing Service Models

Characteristics Of Cloud Computing

• Multi-Tenant: Multi-tenancy is an architecture in which a single instance of a software application serves multiple customers. Each customer is called a tenant.
• Self-Sevice: Self-service cloud computing is a private cloud service where the customer provisions storage and launches applications without an external cloud service provider. With a self-service cloud, users access a web-based portal to request or configure servers and launch applications.
• Elastic (Scale-Up | Scale-Down): Elasticity is the ability to grow or shrink infrastructure resources dynamically as needed to adapt to workload changes in an autonomic manner, maximizing the use of resources. This can result in savings in infrastructure costs overall.
• Web-Based: It means you can access your resources via Web-Based applications.
• Automated: Most of the things in the Cloud are automated, and human intervention is less.
• Pay As You Go Model: You only have to pay when utilizing cloud resources.
• Modern Web-Based Integration:  It allows you to configure multiple application programs to share data in the cloud. In a network that incorporates cloud integration, diverse applications communicate either directly or through third-party software.
• Secure: Cloud services create a copy of the data that you want to store to prevent any form of data loss. If one server loses the data by any chance, the copy version is restored from the other server.

Which Cloud Service Model To Learn?

One of the most common questions I get from my students is which Cloud Computing Service Model I should learn?

• So, If you are System Administrator, you should learn both Infrastructures as a Service (IaaS) and Platform as a Service (PaaS). The reason is that whatever you are building or deploying is over Infrastructure as a Service, ie. PaaS always runs on top of IaaS. That’s the reason you should know both.
• If you are working as a consultant such as a financial consultant or working on a packaged application such as HRMS, SAP, etc., you should learn Software as a Service (SaaS).

Sample Questions

Here are a few sample questions that you should be able to solve after reading this blog.

Q1. Do Amazon Web Services fall into which of the following cloud-computing category?

1. Platform as a Service
2. Software as a Service
3. Infrastructure as a Service
4. Back-end as a Service

Correct Answer: 3
Amazon Web Services falls into the Infrastructure as a Service cloud-computing category.

Q2. Which one of the following can be considered as the most complete cloud computing service model? 

1. PaaS
2. SaaS
3. IaaS

Correct Answer: 2
Explanation: The most complete cloud computing service model must contain the computing hardware and software, as well as the solution itself. Hence the SaaS model has all these features.

Q3. Which one of the following provides the resources or services such as virtual infrastructure, virtual machines, virtual storage, and several other hardware assets?

1. PaaS
2. SaaS
3. IaaS
4. All of the above

Correct Answer: 3
Explanation: The IaaS (Infrastructure as a service) service provider maintains all the infrastructure, while the client is responsible for several other deployment aspects.

Q4. You plan to provide Infrastructure as a Service (IaaS) resources in Azure. Which resource is an example of IaaS? 

1. an Azure web app
2. an Azure virtual machine
3. an Azure logic app
4. an Azure SQL database

Correct Answer: 2.
Explanation/Reference: One can control hardware using IaaS resources and applications using PaaS resources.