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CDN (Content Delivery Network)

Traffic Management

A globally distributed network of edge servers that cache and serve content close to the user.

A CDN is a set of geographically distributed 'edge' servers (Points of Presence) that cache content near end users, cutting round-trip latency and offloading origin servers. Originally used for static assets (images, JS/CSS, video), modern CDNs also do dynamic content acceleration, edge compute (running small functions at the edge), DDoS absorption, and TLS termination.

How it connects

CDN (Content Delivery Network) as the source, with the components it typically interacts with.

CDN edge nodes routeA CDN is aCDNs are commonly placedCDN (ContentDelivery Network)Traffic ManagementLoad BalancerTraffic ManagementCachingPerformanceObject / BlobStorageStorage
  • → Load Balancer: CDN edge nodes route cache-miss traffic back through a regional load balancer to reach origin servers.
  • → Caching: A CDN is a specialized edge cache; the same eviction/TTL/staleness tradeoffs from generic caching apply to CDN edge nodes.
  • → Object / Blob Storage: CDNs are commonly placed directly in front of object storage (e.g. S3 + CloudFront) to serve static assets and media with low latency.

Often used alongside

Load BalancerCachingObject / Blob Storage