MODULE 5 - Network: VPC Fundamentals
Overview
This module introduces Amazon VPC (Virtual Private Cloud), AWS's virtual networking service. You will learn to design isolated and secure networks for your cloud resources.
Learning Objectives
By the end of this module, you will be able to:
- Understand the components of a VPC
- Design public and private subnets
- Configure routing tables
- Understand the role of the Internet Gateway
- Master IP addressing and CIDR notation
Weekly Content
1. Amazon VPC - Overview
┌─────────────────────────────────────────────────────────────┐
│ AMAZON VPC │
├─────────────────────────────────────────────────────────────┤
│ │
│ "Your private network in the AWS cloud" │
│ │
│ ┌─────────────────────────────────────────────────────┐ │
│ │ VPC (10.0.0.0/16) │ │
│ │ │ │
│ │ ┌─────────────────┐ ┌─────────────────┐ │ │
│ │ │ Public Subnet │ │ Private Subnet │ │ │
│ │ │ 10.0.1.0/24 │ │ 10.0.2.0/24 │ │ │
│ │ │ │ │ │ │ │
│ │ │ ┌───────────┐ │ │ ┌───────────┐ │ │ │
│ │ │ │ Web Server│ │ │ │ Database │ │ │ │
│ │ │ └───────────┘ │ │ └───────────┘ │ │ │
│ │ │ │ │ │ │ │ │ │
│ │ └───────┼─────────┘ └───────┼─────────┘ │ │
│ │ │ │ │ │
│ │ ┌───────┴─────────────────────┘ │ │
│ │ │ │ │
│ │ ▼ │ │
│ │ ┌─────────────────┐ │ │
│ │ │ Internet Gateway│ ◄──── Internet Access │ │
│ │ └─────────────────┘ │ │
│ │ │ │
│ └─────────────────────────────────────────────────────┘ │
│ │
└─────────────────────────────────────────────────────────────┘
2. VPC Components
| Component | Description | Role |
|---|---|---|
| VPC | Isolated virtual network | Main container |
| Subnet | Subnetwork in an AZ | Segmentation |
| Route Table | Routing table | Traffic direction |
| Internet Gateway | Internet gateway | Public access |
| NAT Gateway | Address translation | Internet egress for private |
| Security Group | Instance firewall | Instance-level security |
| NACL | Control list | Subnet-level security |
3. CIDR Notation
┌─────────────────────────────────────────────────────────────┐
│ CIDR NOTATION │
├─────────────────────────────────────────────────────────────┤
│ │
│ 10.0.0.0/16 = 65,536 IP addresses │
│ │ │ │
│ │ └── Mask (16 fixed bits) │
│ └── Network address │
│ │
│ Common examples: │
│ │
│ /16 ████████████████████████████████ 65,536 IPs │
│ /20 ████████████████ 4,096 IPs │
│ /24 ████████ 256 IPs │
│ /28 ██ 16 IPs │
│ /32 █ 1 IP │
│ │
│ RFC 1918 private ranges: │
│ • 10.0.0.0/8 (class A) │
│ • 172.16.0.0/12 (class B) │
│ • 192.168.0.0/16 (class C) │
│ │
└─────────────────────────────────────────────────────────────┘
4. Public vs Private Subnet
┌─────────────────────────────────────────────────────────────┐
│ PUBLIC vs PRIVATE SUBNET │
├─────────────────────────────────────────────────────────────┤
│ │
│ PUBLIC SUBNET PRIVATE SUBNET │
│ ────────────── ───────────── │
│ • Route to IGW • No route to IGW │
│ • Auto public IP • Private IP only │
│ • Internet accessible • Isolated from Internet │
│ │
│ Use cases: Use cases: │
│ • Web servers • Databases │
│ • Load balancers • Application servers │
│ • Bastion hosts • Internal services │
│ │
│ Routing table: Routing table: │
│ 10.0.0.0/16 → local 10.0.0.0/16 → local │
│ 0.0.0.0/0 → igw-xxx (no 0.0.0.0/0 route) │
│ │
└─────────────────────────────────────────────────────────────┘
Exercise: VPC Design
Scenario
Design a VPC for a 3-tier web application:
- Tier 1: Load Balancer (public)
- Tier 2: Application Servers (private)
- Tier 3: Database (private)
Constraints
- 2 availability zones
- High availability
- Isolated database
Deliverable
Complete VPC diagram with:
- CIDR ranges
- Subnets per AZ
- Routing tables
- Security Groups
Navigation
- VPC Concepts - Fundamentals
- Subnets and Routing - Configuration
- Internet Gateway - Public access
- CIDR Calculator - Address calculation
- Validation Quiz - 30 questions to validate your knowledge
- Lab: VPC Schema - Practical exercise
Next week: MODULE 6 - Network Security