Today, cloud computing is one of the most promising upcoming technologies and enterprise—no matter how big or small, almost every companies and organization has adopted it as a part of their IT strategy. It is difficult these days to have any meaningful conversation about an IT strategy without including cloud computing in the overall solution discussions.

Cloud computing, or simply the cloud in layman terms, refers to the availability of resources on the internet. These resources are made available to users on the internet as services. For example, storage is available on demand through the internet to users for them to store their files, documents, and so on. Here, storage is a service provided by a cloud provider.

A cloud provider is an enterprise or consortium of companies that provide cloud services to other enterprises and consumers. They host and manage the services on behalf of the user. They are responsible for enabling and maintaining the health of services. Typically, there are large data centers across the globe opened by cloud providers to cater to IT demands from users.

Cloud resources consist of hosting services on on-demand infrastructure, such as compute, network, and storage facilities. This flavor of the cloud is known as Infrastructure as a Service.

Cloud adoption is at an all-time high and is further growing because of the advantages it provides. Some of these advantages are mentioned here:

• Pay-as-you-go: Customers do not need to purchase hardware and software for cloud resources. There is no capital expenditure for using cloud resource. Customers just pay for the resource for the time they are used.
• Global access: Cloud resources are available globally via the internet. Customers can access their resources on demand from any where.
• Unlimited resources: The scale of the cloud is unlimited. Customers can provision as many resources as they want, without any constraints. This is also known as unlimited scalability.
• Managed Services: The cloud provides numerous services that are managed by the cloud provider for customers. This takes away the technical and financial burdens from customers.

There are three different deployment patterns available on Azure. They are

• Infrastructure as a Service (also popularly known as IaaS)
• Platform as a Service (also popularly known as PaaS)
• Software as a Service (also popularly known as SaaS)

The difference between these three deployment patterns is the level of control exercised by customer viz-a-viz Azure. The next image shows different levels of control within each of these deployment patterns.

It is clear from the previous image that customers have more control using IaaS deployments and it keeps reducing from PaaS to SaaS deployments.

IaaS is a deployment types in which customer provision their own infrastructure on Azure. Azure provides infrastructure resources and customers can provision them on demand. Customer are responsible for maintaining and governing their infrastructure. Azure will ensure to maintain the physical infrastructure on which these virtual infrastructure resources are hosted. Under this approach, customers needs active management and operations on the Azure environment.

PaaS takes away infrastructure deployments and control from customer. This is a higher level abstraction compared to infrastructure as service. In this approach, customers bring their application, code and data and deploy them on Azure provided platform. These platform are managed and governed by Azure and customer are responsible solely for their application. Customers perform activities related to their applications deployment only. This model provides faster and easier options for deployment of applications compared to infrastructure as a service.

SaaS is a level higher abstraction compared to PaaS. In this approach, software and its services are available for end user consumption. Customer bring only their data into these services. Customers do not have any control over these services.