Azure public cloud architectures

Now you have a better understanding of the different cloud models, let's focus some more on public cloud architectures.

Infrastructure as a Service (IaaS)

Part of this first chapter is dedicated to migrating and running your business applications in an Infrastructure as a Service (IaaS) model, using similar concepts to those related to your on-premises datacenter, with virtual networking, virtual storage, and virtual machines as the main architectural building blocks.

However, that is not the only way that you can run your applications in Azure. As a segue to other chapters in this book, let me briefly describe where Azure can help in business innovation, or the digital transformation of your workloads, using other architectures besides virtual machines.

Platform as a Service options (App Service, SQL Database, Azure Container Instances, and Azure Kubernetes Service)

Platform as a Service (PaaS) refers to running your workloads in Azure without deploying virtual machines. You could, for example, run a web application in Azure App Service without deploying the underlying virtual machine first. This brings efficiency and optimization, since you have less operational management to worry about. Alternatively, you could use a service such as Azure SQL Database or Cosmos DB, allowing you to run the exact same flavor of your database solution, but again without having to take any virtual machines into consideration. As mentioned earlier, having this flexibility of architecture while also not needing to deploy and manage your own infrastructure dependencies anymore provides room for innovation. In addition, new capabilities are easier to adopt in a PaaS model than they are in an IaaS model, as the deployment of the service is much faster, thanks to the lack of operating system dependency and development language support, to name just a couple of reasons. PaaS can also be cost-effective, as most PaaS services are cheaper than their IaaS alternatives (for example, using Azure web apps is cheaper than deploying an Azure web virtual machine with the same performance characteristics).

Serverless (Functions, Cosmos DB, Logic Apps, and Cognitive Services)

Outside of these two standard concepts of IaaS and PaaS, you also have serverless and microservices. Looking at Azure serverless services, one option is to use Azure Functions, a serverless compute service that enables you to run code on demand without having to explicitly provision or manage infrastructure. You can use Azure Functions to run a script or piece of code in response to a variety of events. Another serverless service offered by Azure is Azure Logic Apps, a business workflow engine that provides connectors to more than 200 business applications, such as Dropbox, OneDrive, SAP, DocuSign, and Adobe. With Logic Apps, you can build a step-by-step workflow with logical intelligence to replace your current chain of complex, (mostly) virtual machine-based workloads.

Microservices is an application development approach in which a more complex application architecture, known as a monolithic application, gets divided into several smaller components. Each component has a single purpose, such as managing product ordering, order payment, or shipment follow-up, in a broader e-commerce platform solution. Microservices are a very popular strategy for migrating (legacy) applications to the public cloud. Microservices are also known as containers or containerized applications. At present, Docker (http://www.docker.com) is the standard container format for microservices and is fully supported by Azure.

Azure allows you to bring your containers into Azure and run them with Azure Container Instances (ACI) as a standalone container workload. Or, if you are looking for more advanced orchestration capabilities, you can also deploy Azure Kubernetes Service (AKS), providing a Kubernetes clustered environment as a service. Besides the advantage of legacy app support, containers are also very interesting because they are lightweight, running one specific task, and can easily be moved around across different environments. The same container image can run on a developer's Mac, be pushed into an Azure container registry, run on top of Azure Web App for Containers, run as an Azure container instance, or run in your own datacenter on top of RedHat OpenShift infrastructure or some other public cloud infrastructure. This is the main reason why containers are so popular today.

How can these different cloud architectures lead to business innovation? For a long time, businesses were struggling in optimizing IT and streamlining IT processes, searching for ways to align operations and developer teams—not always with huge success. However, by shifting from infrastructure (IaaS) to platform services or serverless (PaaS/SaaS), a huge part of this dependency is removed. The flexibility of using the public cloud and the different operational models it provides will definitely help in business innovation.

Outside of the technical IT-side of optimization, this could also lead to freeing up more resources and saving money that the business can then invest in new innovation. Let's look at some more reasons for moving to the cloud.