Many teams believe their CDN already protects them from DDoS. It is an understandable assumption — a CDN sits in front of your site, absorbs a lot of traffic, and marketing pages often blur the line. But a CDN and a DDoS-protection service are built for different jobs, and relying on one for the other leaves a gap that attackers know how to find.
What a CDN Is Actually For
A content delivery network exists to make your site fast and cheap, not to defend it. Its whole design is about serving cached copies of content from a location near the visitor.
- Geographic distribution: cached content served from the nearest point of presence.
- Lower origin load and bandwidth cost, because the CDN answers repeat requests itself.
- TLS termination, HTTP/2 and HTTP/3, and edge routing.
- Some incidental resilience: if an attack hits a cacheable URL and the CDN's capacity exceeds it, the origin never feels it.
That last point is real but narrow. It only holds when the attacked resource is cacheable and the CDN's spare capacity happens to exceed the attack. Neither is guaranteed, and an attacker who understands CDNs will deliberately break both assumptions.
Where a CDN Falls Short Under Attack
- Cache-busting: appending a unique query string to every request forces a cache miss, so the whole flood lands on your origin.
- Uncacheable endpoints: APIs, logins, search and checkout are never cached, and they are exactly what Layer 7 attacks target.
- Behavioural blindness: a CDN forwards valid-looking requests; it is not built to tell a real user from a bot sending the same valid request thousands of times.
- Origin exposure: many CDN setups leave the origin IP reachable directly, so an attacker who finds it bypasses the CDN entirely.
Speed is not security
A CDN answers the question 'how do I serve this faster?' DDoS protection answers 'how do I stay up when someone is trying to take me down?' They overlap at the edge, but optimising for one does not give you the other.
The Right Architecture: Use Both
The two are complementary, not competing. Keep the CDN for performance — caching, edge delivery, cheaper bandwidth — and put a dedicated protection layer in front for security. With Akarguard you route your domain through the reverse-proxy edge with a DNS change; it filters application-layer attacks, challenges automated clients, applies your WAF and rate limits, and keeps your origin IP hidden so direct floods have no target. Clean traffic is then forwarded on to your CDN or origin. You do not have to choose between fast and defended.
One honest caveat: Akarguard is a Layer 7 service. It filters the application-layer attacks and hides your origin; raw volumetric floods against the network are handled upstream by your host or transit provider, the same as with a CDN. The point is that the parts a CDN leaves exposed — uncacheable endpoints, behaviour, origin privacy — are exactly the parts a protection layer covers.