Edge caching is the practice of storing copies of web content on servers close to users, often inside a content delivery network. Instead of every request reaching the origin server, nearby edge nodes can answer with a cached response, which lowers latency and reduces load on the core infrastructure.
In cyber security, edge caching matters because it can improve resilience during traffic spikes and help absorb some denial-of-service pressure. It also changes the attack surface: if cache rules are misconfigured, attackers may poison cached objects, serve stale or unauthorized content, or bypass protections by manipulating headers and URLs. Defenders monitor cache keys, TTLs, invalidation behavior, and origin shielding to keep content consistent and secure. In live services, edge caching is often the difference between a stable experience and an overloaded origin when many users arrive at once.