CDN (Content Delivery Network) Simulator — Interactive System Design Lab

Simulate user requests hitting CDN edge nodes vs. origin servers. Observe cache hits (fast, served from the edge) and misses (slow, round-trip to origin), invalidate caches globally, and see the latency difference between serving from the edge vs. crossing the globe to the origin.

See how edge caching reduces latency and origin load.

This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.

Concepts covered

  • CDN
  • content delivery network
  • edge caching
  • cache hit rate
  • origin server
  • latency

Read the guide

  • CDN (Content Delivery Network) — Speed isn't just about fast servers; it's about physics. Learn how CDNs beat the speed of light by moving content closer to your users.
  • DNS (Domain Name System) — The Phonebook of the Internet. But unlike a physical phonebook, this one is distributed, hierarchical, and capable of intelligent routing based on who is asking.

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