Learning Objectives
By the end of this chapter, you will be able to:
- Describe cloud computing and the benefits of using cloud services
- Define cloud computing and identify the role of high availability and scalability
- Describe the shared responsibility model and how reliability and predictability arise from it
- Define the public, private, and hybrid cloud models and how each affects security and governance
- Identify appropriate use cases for each cloud model and the manageability benefits that follow
- Describe the consumption-based model and the cloud service types it pays for
- Compare cloud pricing models and recognise Infrastructure as a Service (IaaS)
- Describe serverless computing and Platform as a Service (PaaS)
Executive Summary
- Cloud computing rents shared infrastructure from a hyperscale provider, replacing fixed capital expenditure with metered operating expenditure that scales with demand.
- The shared responsibility model divides duties between Microsoft and the customer; the division shifts as a workload moves from IaaS through PaaS to SaaS, and the customer keeps responsibility for data and accounts at every layer.
- Public, private, and hybrid cloud each carry different sovereignty, cost, and control trade-offs; the correct choice depends on the workload profile, the regulator involved, and the budget shape.
- Pricing models combine pay-as-you-go, reserved capacity, spot instances, and savings plans; matched correctly to a workload they cut spend without sacrificing capacity.
- Serverless removes server management entirely, billing per execution rather than per reserved hour, and sits inside the broader Platform as a Service family on Azure.
Assumptions
- The reader has general IT literacy: knows what a server, an operating system, a database, and a web application are.
- All examples use Microsoft Azure terminology, even where the underlying concept is provider-neutral; the cloud model definitions remain accurate against other public clouds, but service names belong to Azure.
- Identity refers to Microsoft Entra ID throughout this chapter; the older name "Azure Active Directory" is not used.
- Scenarios reference fictional organisations (Contoso, Northwind, Fabrikam, Wide World Importers) that have no relationship to any real company.