What are the models in cloud computing, their types, definitions, examples, where to use, advantages or disadvantages?

Cloud computing is divided into two primary sets of models:

  1. Service-Based Models 
  2. Deployment Models

 

1) Service-Based Models:

These models define the type of services offered by the cloud provider. They determine what level of control and flexibility the user has over the infrastructure, platform, or software. 

Service-based models are 4 Types:

  1. Infrastructure as a Service (IaaS)
  2. Platform as a Service (PaaS)
  3. Software as a Service (SaaS)
  4. Function as a Service (FaaS)

1) Infrastructure as a Service (IaaS):

Definition:

Provides the basic building blocks like virtual servers, storage, and networks over the internet. You manage the system, but the hardware is maintained by the cloud provider.

Features:

  • Gives you virtual machines, storage, and network access.
  • Highly scalable—you can add or remove resources as needed.
  • Pay only for what you use.

Examples:

AWS EC2, Microsoft Azure Virtual Machines, Google Compute Engine.

Advantages:

  • Full control over your system setup.
  • Cost-effective for businesses that need flexibility.
  • No need to buy and maintain physical hardware.

Disadvantages:

  • Requires technical knowledge to set up and manage.
  • You’re responsible for updates, security, and backups.

 

2) Platform as a Service (PaaS):

Definition:

Provides a ready-made platform for developers to build, test, and deploy applications without worrying about hardware or infrastructure.

Features:

  • Tools for application development, like programming languages and databases.
  • Automated updates and scaling of resources.
  • Focused on simplifying app development.

Examples:

Google App Engine, Microsoft Azure App Services, Heroku.

Advantages:

  • No need to manage the backend or hardware.
  • Saves time for developers to focus on coding.
  • Automatic updates and scalability.

Disadvantages:

  • Limited customization options compared to IaaS.
  • Dependent on the provider for system reliability and updates.

 

3) Software as a Service (SaaS):

Definition:

Provides ready-to-use software applications over the internet on a subscription basis. No installation or maintenance is required.

Features:

  • Access through a browser or app—no downloads needed.
  • Managed by the provider, including updates and security.
  • Available from anywhere with an internet connection.

Examples:

Gmail, Microsoft 365, Google Drive, Salesforce.

Advantages:

  • Easy to use and quick to get started.
  • No need for maintenance—everything is handled by the provider.
  • Accessible from any device with the internet.

Disadvantages:

  • Less control over the software (features and data).
  • Can become expensive with ongoing subscriptions.
  • Requires a reliable internet connection to work.

 

4) Function as a Service (FaaS):

Definition:

Also called “serverless computing,” it lets you run small pieces of code that do specific tasks without managing the servers.

Features:

  • Runs code only when needed, not continuously.
  • You only pay for the execution time of your code.
  • No need to worry about hardware or system setup.

Examples:

AWS Lambda, Google Cloud Functions, Azure Functions.

Advantages:

  • Highly cost-effective—you pay only for what you use.
  • Scales automatically based on the demand.
  • Simplifies development by focusing only on the code.

Disadvantages:

  • Not suitable for long-running processes.
  • Limited control over the infrastructure.
  • May face latency issues if used at a large scale.

 

14+ interview questions with simple and clear answers covering service-based models in cloud computing

Question 1. What are the main models of cloud computing?

Answer: Cloud computing is divided into two main models:

  • Service-Based Models (IaaS, PaaS, SaaS, FaaS).
  • Deployment Models (Public Cloud, Private Cloud, Hybrid Cloud, Community Cloud).

 

Question 2. What are service-based models in cloud computing?

Answer: Service-based models define the type of services offered by a cloud provider. These include:

  • IaaS (Infrastructure as a Service): Basic hardware like servers and storage.
  • PaaS (Platform as a Service): A platform for developers to build apps.
  • SaaS (Software as a Service): Ready-to-use software like Gmail or Microsoft 365.
  • FaaS (Function as a Service): Running small code snippets without managing servers.

 

Question 3. What is IaaS, and where is it used?

Answer: IaaS provides virtual machines, storage, and networks over the internet.

  • Use Case: When you need control over the system setup, like hosting a custom website or database.
  • Example: AWS EC2, Google Compute Engine.

 

Question 4. What are the advantages of IaaS?

Answer:

  • Full control over your system setup.
  • Cost-effective for businesses that need flexibility.
  • No need to maintain physical hardware.

 

Question 5. What is a disadvantage of using IaaS?

Answer:

  • Requires technical knowledge to manage.
  • You’re responsible for security, updates, and backups.

 

Question 6. What is PaaS, and how is it different from IaaS?

Answer: PaaS provides a platform for developers to build, test, and deploy applications without managing hardware.

Difference:

  • IaaS gives you hardware control.
  • PaaS focuses on simplifying app development by managing the backend for you.

Example: Google App Engine, Heroku.

 

Question 7. What are the benefits of PaaS?

Answer: Developers can focus on coding without worrying about hardware.

  • Automatic updates and scalability.
  • Saves time and resources.

 

Question 8. When should you avoid using PaaS?

Answer:

  • When you need full customization over infrastructure.
  • If you rely on the platform provider’s reliability.

 

Question 9. What is SaaS, and can you give some examples?

Answer:

  • SaaS provides ready-to-use software over the internet.
  • Examples: Gmail, Microsoft 365, Google Drive, Salesforce.

 

Question 10. What are the advantages and disadvantages of SaaS?

Answer:

Advantages:

  • Easy to use and quick to set up.
  • No maintenance required—it’s handled by the provider.
  • Accessible from anywhere.

Disadvantages:

  • Limited control over features and data.
  • Can become costly with ongoing subscriptions.
  • Needs a stable internet connection.

 

Question 11. What is FaaS, and how does it work?

Answer: FaaS (Function as a Service) runs small pieces of code for specific tasks without managing servers.

Example:

AWS Lambda, Google Cloud Functions.

How it works:

You upload your code, and the provider runs it when triggered. You only pay for the time the code runs.

 

Question 12. What are the pros and cons of FaaS?

Answer:

Advantages:

  • Cost-effective—you pay only when the code runs.
  • Automatically scales to handle demand.
  • Focus on the code, not the servers.

Disadvantages:

  • Not suitable for long-running tasks.
  • Limited control over the infrastructure.

 

Tags:

Leave a comment

You must be logged in to post a comment.

0 Comments