Cloud Migration
Study notes covering cloud fundamentals, migration strategy, Azure App Service, and PaaS databases. Each module has notes, a cheat sheet, and a quiz using real exam-style questions.
Cloud computing delivers computing resources over the internet using remote servers in data centers. Instead of buying and maintaining hardware, you pay only for what you use.
The three service models define who manages which layer of the stack.
IaaS (Infrastructure as a Service): You rent virtualized compute, storage, and networking. You manage the OS upward. The provider handles hardware, network, and virtualization. Azure example: Virtual Machines.
PaaS (Platform as a Service): Managed platform for deploying apps. Provider handles OS, runtime, and middleware. You manage your app and data only. Azure example: Azure App Service.
SaaS (Software as a Service): Complete software delivered over the internet on subscription. Provider manages everything including the application. Examples: Microsoft 365, Salesforce.
The analogy to remember: IaaS is renting land and building. PaaS is renting a furnished house and decorating. SaaS is staying in a hotel where everything is handled for you.
The four deployment models: Public cloud is shared infrastructure from third-party vendors. Private cloud is dedicated infrastructure for one organization. Hybrid cloud combines public and private. Multi-cloud uses multiple providers simultaneously to avoid vendor lock-in.
The three major cloud providers: Azure excels at enterprise and hybrid workloads. AWS has the broadest service catalog and largest market share. GCP leads in data analytics and AI with BigQuery and Vertex AI.