Networking & Content Delivery
Amazon CloudFront
Global CDN with edge caching
Amazon CloudFront is a content delivery network that caches content at global edge locations, reducing latency and offloading origins. It integrates with S3, ALBs, API Gateway, and supports HTTPS via ACM, geo-restriction, signed URLs, and WAF.
When to use it
- Static/dynamic web content for global users
- Caching S3 content at edges with Origin Access Control
- HTTPS termination and WAF protection at the edge
- Media streaming and large file downloads
When NOT to use it
- Non-cacheable TCP/UDP acceleration where Global Accelerator fits better
- Content that must never be cached without careful cache-control settings
Key exam points
- Origin Access Control secures S3 origins so only CloudFront can fetch objects
- TTL and cache keys control hit rates; invalidation clears cached objects
- Works with AWS WAF and Shield for edge security
- Signed URLs/cookies restrict access to paid or private content
Compared with
- Amazon S3 — S3 stores the content; CloudFront caches and serves it close to users.