☁️ Cloud Essentials Overview

🌐 Cloud Delivery Models

Cloud deployment models can be grouped into three main service types:

🖥️ On-Premises (Traditional)

Everything is hosted in your own data center. You are responsible for:

  • Physical servers
  • Networking and firewalls
  • Storage (disks, SANs)
  • Virtualization layer
  • Operating systems
  • Middleware and applications

All hardware and software must be maintained, patched, and secured manually.

🏗️ IaaS – Infrastructure as a Service

In IaaS, the cloud provider manages:

  • Physical servers
  • Storage hardware
  • Networking
  • Virtualization

You manage:

  • Operating systems
  • Runtime environments
  • Databases
  • Application logic
  • Security (at the OS/app level)

📌 Examples: EC2, S3, VPC, EBS

🧱 PaaS – Platform as a Service

In PaaS, the provider handles everything except the application code and data. You manage:

  • Your application logic
  • The data it needs

📌 Examples: AWS Elastic Beanstalk, Heroku, Google App Engine

💻 SaaS – Software as a Service

In SaaS, the provider manages everything — you simply use the product.

📌 Examples: Gmail, Dropbox, Salesforce, Microsoft 365

🌍 AWS Global Infrastructure

Amazon Web Services (AWS) offers a highly available and redundant infrastructure built on three core components:

🗺️ Regions

A region is a geographical area (e.g., eu-west-2 = London). Each region contains multiple Availability Zones (AZs) and is isolated from other regions for fault tolerance and compliance.

  • AWS has 30+ regions globally
  • Service availability and pricing vary by region

🧩 Availability Zones (AZs)

An AZ is one or more data centers with independent power, cooling, and networking. They are:

  • Physically separated
  • Connected by high-speed, low-latency private fiber
  • Typically 3 to 6 AZs per region

✅ Best practice: Deploy workloads across multiple AZs for high availability

🚦 Points of Presence (PoPs) / Edge Locations

AWS maintains over 400 Edge Locations and regional caches to serve content faster, closer to the user.

  • Used by services like CloudFront and Route 53
  • Improve latency, performance, and content delivery
  • You can serve content globally without deploying infrastructure in every country

🧭 Note:
This overview introduces core cloud models and AWS infrastructure components.
More complex AWS services and architectural stacks (e.g., EC2, IAM, S3, VPC, Lambda, Route 53, etc.)
will be explored in detail in later modules as part of this hands-on journey.