Task Statement 3.4: Determine high-performing and/or scalable network architectures.
📘AWS Certified Solutions Architect – (SAA-C03)
1. What is Edge Networking?
Edge networking means delivering content and applications to users from locations that are physically closer to them instead of from a central server.
Key Idea:
- Users connect to a nearby AWS edge location
- This reduces:
- Latency (delay)
- Network congestion
- Load on origin servers
2. AWS Edge Locations
AWS has Edge Locations around the world.
They are used by:
- Amazon CloudFront
- AWS Global Accelerator
- AWS Shield (DDoS protection)
- AWS WAF
Purpose:
- Cache content
- Route traffic efficiently
- Improve performance and availability
3. Amazon CloudFront
What is it?
Amazon CloudFront is a Content Delivery Network (CDN).
It delivers:
- Static content (images, CSS, JS)
- Dynamic content (APIs, web apps)
- Streaming content
from edge locations close to users.
How CloudFront Works
- User requests content
- Request goes to nearest edge location
- If content is cached → returned immediately
- If not cached → fetched from origin (S3, EC2, ALB, etc.)
- Cached for future requests
Key Features
1. Caching
- Stores copies of content at edge locations
- Reduces load on backend systems
2. Origins
Supported origins:
- Amazon S3
- EC2 instances
- Application Load Balancer (ALB)
- On-premises servers
3. Cache Control
- Control how long content stays cached using:
- TTL (Time To Live)
- Cache headers
4. Security
- Integration with:
- AWS Shield (DDoS protection)
- AWS WAF (web filtering)
- HTTPS support
- Signed URLs and cookies
5. Performance Optimization
- Compression (Gzip/Brotli)
- HTTP/2 and HTTP/3 support
CloudFront Use Cases (Exam-Focused)
1. Static Content Delivery
- Serve images, videos, JavaScript files from edge locations
2. API Acceleration
- Speed up API responses globally
3. Dynamic Content Delivery
- Reduce latency even for non-cacheable content
4. Streaming
- Video streaming with low buffering
Important Exam Points
- CloudFront = CDN + caching
- Works well with S3, ALB, EC2
- Reduces latency and improves performance
- Supports both static and dynamic content
- Uses edge locations
4. AWS Global Accelerator
What is it?
AWS Global Accelerator improves application availability and performance using the AWS global network.
It provides:
- Static IP addresses
- Intelligent traffic routing
- Fast failover
How Global Accelerator Works
- User connects to a static IP
- Traffic enters AWS network at nearest edge location
- AWS routes traffic through its private global network
- Sends to the optimal endpoint (ALB, EC2, etc.)
Key Features
1. Static IP Addresses
- Provides 2 fixed IP addresses
- Useful for:
- DNS simplification
- Firewall whitelisting
2. Health Checks
- Continuously monitors endpoints
- Routes traffic only to healthy endpoints
3. Traffic Routing
- Routes to closest or best-performing region
- Can shift traffic between regions
4. Failover Support
- Automatically reroutes traffic if endpoint fails
5. TCP/UDP Support
- Works at network layer (Layer 4)
Global Accelerator Use Cases
1. Multi-Region Applications
- Route users to nearest healthy region
2. High Availability Systems
- Automatic failover between regions
3. Real-Time Applications
- Gaming servers
- Financial systems
- APIs needing low latency
Important Exam Points
- Uses AWS global network (not public internet)
- Provides static IPs
- Improves:
- Availability
- Fault tolerance
- Performance
- Works at Layer 4 (TCP/UDP)
5. CloudFront vs Global Accelerator
This comparison is very important for the exam:
| Feature | CloudFront | Global Accelerator |
|---|---|---|
| Type | CDN | Network routing service |
| Layer | Layer 7 (HTTP/HTTPS) | Layer 4 (TCP/UDP) |
| Main Purpose | Content caching & delivery | Traffic routing & failover |
| Caching | Yes | No |
| Static IP | No | Yes |
| Protocols | HTTP/HTTPS | TCP/UDP |
| Use Case | Websites, APIs, media | Multi-region apps, failover |
6. When to Use Which (Exam Decision Guide)
Use CloudFront when:
- You need caching
- You deliver static or dynamic content
- You want to reduce latency globally
- You use S3 for content delivery
Use Global Accelerator when:
- You need static IP addresses
- You want fast regional failover
- You have multi-region applications
- You need consistent performance for TCP/UDP traffic
Use Both Together (Important Scenario)
You can combine:
- CloudFront → for caching and content delivery
- Global Accelerator → for intelligent routing and failover
7. Key Differences from Other Services (Exam Traps)
CloudFront vs S3
- S3 stores data
- CloudFront delivers cached content faster
Global Accelerator vs Route 53
| Feature | Route 53 | Global Accelerator |
|---|---|---|
| Type | DNS-based routing | Network-level routing |
| Failover speed | Depends on DNS TTL | Immediate |
| Static IP | No | Yes |
8. Performance Benefits
Both services:
- Reduce latency
- Improve user experience
- Use AWS global infrastructure
But:
- CloudFront → reduces latency via caching
- Global Accelerator → reduces latency via optimized routing
9. Exam Tips (Very Important)
- If question mentions:
- “cache”, “static files”, “CDN” → CloudFront
- “static IP”, “failover”, “multi-region routing” → Global Accelerator
- If performance + caching needed → CloudFront
- If performance + availability + failover needed → Global Accelerator
10. Summary
- Edge networking brings content closer to users
- CloudFront:
- CDN
- Caching
- HTTP/HTTPS
- Global Accelerator:
- Network routing
- Static IPs
- TCP/UDP
- Failover
Both are critical for designing:
- High-performance
- Scalable
- Globally distributed architectures
