CDN Caching: Strategies, Headers, and Optimization

Caching is the heart of CDN performance. Every millisecond of latency reduction and every origin request eliminated comes down to effective caching strategy. This cluster covers the complete caching lifecycle — from setting the right headers to optimizing hit ratios and handling invalidation.

Articles in This Cluster

1. Caching StrategiesOverview of CDN caching approaches.
2. Cache-Control HeadersMastering HTTP cache headers.
3. Cache Key DesignWhat goes into the cache key and why it matters.
4. Cache InvalidationPurging and refreshing cached content.
5. TTL OptimizationSetting optimal time-to-live values.
6. Stale-While-RevalidateServing stale content during revalidation.
7. Cache HierarchyMulti-tier caching and origin shields.
8. Cache WarmingPre-populating caches for optimal performance.
9. Browser vs CDN CacheUnderstanding the two caching layers.
10. Dynamic Content CachingCaching personalized and dynamic responses.
11. Negative CachingCaching error responses strategically.
12. Cache Hit Ratio OptimizationMaximizing cache efficiency.
13. Cache Stampede PreventionPreventing thundering herd problems.
14. Edge Side Includes (ESI)Assembling pages at the edge.

This topic cluster contains 14 articles progressing from foundational concepts to advanced implementations. Read them in order for a comprehensive understanding, or jump to any topic that interests you.