====== CloudFront (CDN) ======

**What it is:** AWS Content Delivery Network (CDN) that delivers content via edge locations.

**What it’s for:**
  * Speed up delivery of websites, images, videos, APIs (in some cases).
  * Add security features like HTTPS, WAF integration, DDoS protection (via Shield).

**Core components:**
  * **Distribution**: CloudFront configuration.
  * **Origin**: where CloudFront fetches content (S3, ALB, EC2, custom).
  * **Cache behavior**: rules for caching, headers, cookies, query strings.
  * **TTL**: cache time-to-live.

**Exam cues:**
  * “global users, faster static content” → CloudFront.
  * “reduce load on origin” → caching with CloudFront.

**Hard words:**
  * *distribution* /ˌdɪstrɪˈbjuːʃn/: phân phối/cấu hình phân phối
  * *behavior* /bɪˈheɪvjər/: hành vi (rule xử lý)
  * *cookie* /ˈkʊki/: cookie
  * *query string* /ˈkwɪri strɪŋ/: chuỗi tham số URL
  * *time-to-live (TTL)* /ˌtaɪm tə ˈlɪv/: thời gian sống (thời hạn cache)