CDN Vs API Gateway
CDN (Content Delivery Network) and API Gateway serve very different roles in modern architectures, though both act as intermediaries between clients and servers. Here’s a breakdown to clarify their purposes, differences, and when to use each:
🌍 CDN (Content Delivery Network)
Purpose:
To distribute and cache static content like images, CSS, JavaScript, fonts, and videos closer to the user's geographic location for faster load times.
| Feature | Description |
|---|---|
| Primary Use | Caching and delivering static assets |
| Works With | Web assets, files, media (not APIs) |
| Performance Benefit | Reduces latency via edge servers |
| Security Benefit | DDoS protection, TLS offloading |
| Examples | Cloudflare, Akamai, Amazon CloudFront, Fastly |
| Typical Content | HTML, JS, CSS, images, videos, fonts |
| Protocols | HTTP/HTTPS |
🔀 API Gateway
Purpose:
To manage, route, and secure API requests coming into a microservices or backend system.
| Feature | Description |
|---|---|
| Primary Use | API routing, security, throttling, monitoring |
| Works With | REST, GraphQL, gRPC, SOAP APIs |
| Performance Benefit | Caching responses, rate limiting |
| Security Benefit | Authentication (OAuth, JWT), IP whitelisting, SSL termination |
| Examples | Amazon API Gateway, Kong, Apigee, NGINX, Azure API Management |
| Typical Content | Dynamic JSON/XML data |
| Protocols | HTTP/HTTPS, WebSocket, gRPC |
⚖️ CDN vs API Gateway – Key Differences:
| Feature | CDN | API Gateway |
|---|---|---|
| Purpose | Deliver static content | Manage and secure API traffic |
| Use Case | Speed up websites, media delivery | Handle backend API requests |
| Content Type | Static assets | Dynamic API responses |
| Caching | Strong focus on caching | Optional caching (for GETs) |
| Security | DDoS, TLS, edge firewall | Auth, throttling, IP filtering |
| Integration | Edge of network | Entry point to backend/microservices |
✅ When to Use:
- Use a CDN for:
- Accelerating web page load speeds
- Distributing videos, images, fonts, etc.
- Offloading traffic from your origin server
- Use an API Gateway for:
- Routing requests to microservices
- Applying authentication/authorization
- Rate limiting and versioning APIs