Basic cloud concepts Part - 1

 

Let us start with very basic concepts of cloud computing. 

 

What is cloud computing ?

Cloud computing is the delivery of computing services over the internet.

Computing services include common IT infrastructure such as virtual machines, storage, databases, and networking.

Cloud Models

Cloud models define how cloud computing services are deployed and managed. They are broadly categorized into deployment models and service models.

Cloud Deployment Models:

The cloud deployment model defines the deployment type of cloud resources. The three main cloud models are: Private, Public, and Hybrid .

Public Cloud – Services are hosted by a cloud provider and shared among multiple customers (e.g., Azure, AWS, Google Cloud).

Private Cloud – Dedicated infrastructure for a single organization, offering more control and security.

Hybrid Cloud – A mix of public and private clouds, allowing data and applications to move between them.

The following table highlights a few key comparative aspects between the cloud models.

Multi-Cloud –  A fourth, and increasingly likely scenario is a multi-cloud scenario. In a multi-cloud scenario, you use multiple public cloud providers. Maybe you use different features from different cloud providers. In a multi-cloud environment you deal with two (or more) public cloud providers and manage resources and security in both environments.

Cloud Service Models:

Infrastructure as a Service (IaaS) – In an IaaS model, the cloud provider is responsible for maintaining the hardware, network connectivity (to the internet), and physical security. You’re responsible for everything else: operating system installation, configuration, and maintenance; network configuration; database and storage configuration; and so on.

With IaaS, you’re essentially renting the hardware in a cloud datacenter, but what you do with that hardware is up to you.

Provides virtual machines, storage, and networking (e.g., Azure Virtual Machines).

Some common scenarios where IaaS might make sense include: (Very important for exam)

•  Lift-and-shift migration: You’re standing up cloud resources similar to your on-prem datacenter, and then simply moving the things running on-prem to running on the IaaS infrastructure.
• Testing and development: You have established configurations for development and test environments that you need to rapidly replicate. You can stand up or shut down the different environments rapidly with an IaaS structure, while maintaining complete control.

Platform as a Service (PaaS) – In a PaaS environment, the cloud provider maintains the physical infrastructure, physical security, and connection to the internet. They also maintain the operating systems, middleware, development tools, and business intelligence services that make up a cloud solution.

In a PaaS scenario, you don't have to worry about the licensing or patching for operating systems and databases.

PaaS is well suited to provide a complete development environment without the headache of maintaining all the development infrastructure.

Offers a managed environment for application development (e.g., Azure App Services).

Some common scenarios where PaaS might make sense include:

• Development framework: PaaS provides a framework that developers can build upon to develop or customize cloud-based applications. Similar to the way you create an Excel macro, PaaS lets developers create applications using built-in software components. Cloud features such as scalability, high-availability, and multi-tenant capability are included, reducing the amount of coding that developers must do.
• Analytics or business intelligence: Tools provided as a service with PaaS allow organizations to analyze and mine their data, finding insights and patterns and predicting outcomes to improve forecasting, product design decisions, investment returns, and other business decisions.

Software as a Service (SaaS) – Software as a service (SaaS) is the most complete cloud service model from a product perspective. With SaaS, you’re essentially renting or using a fully developed application. Email, financial software, messaging applications, and connectivity software are all common examples of a SaaS implementation.

Delivers fully managed applications over the internet (e.g., Microsoft 365).

Some common scenarios for SaaS are:

• Email and messaging.
• Business productivity applications.
• Finance and expense tracking.

The shared responsibility model 

The Shared Responsibility Model in cloud computing defines the division of security and operational responsibilities between the cloud service provider (CSP) and the customer.

With the shared responsibility model, these responsibilities get shared between the cloud provider and the consumer. Physical security, power, cooling, and network connectivity are the responsibility of the cloud provider.

At the same time, the consumer is responsible for the data and information stored in the cloud. (You wouldn’t want the cloud provider to be able to read your information.) The consumer is also responsible for access security, meaning you only give access to those who need it.

The following diagram highlights how the Shared Responsibility Model informs who is responsible for what, depending on the cloud service type.

You’ll always be responsible for:

•  The information and data stored in the cloud

•  Devices that are allowed to connect to your cloud (cell phones, computers, and so on)

• The accounts and identities of the people, services, and devices within your organization

The cloud provider is always responsible for:

• The physical datacenter
• The physical network
• The physical hosts

Your service model will determine responsibility for things like:

• Operating systems
• Network controls
• Applications
• Identity and infrastructure

This concludes the main theory part of basic cloud concept. go through the topics carefully. 

Several questions comes from this part in AZ-900 certification exam which we will discuss later.

In the next part we will discuss some important terms related to cloud computing and also important for exam point of view.

So keep follow my blog. I will discuss in such way that you don't have to go anywhere for AZ-900 preparation.  

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