CDN Security & Performance Optimization 5

Question 1

A CDN operator needs to prevent hotlinking — third-party sites embedding their customers' images. Which security feature is most effective?

Accepted Answer

Signed URL or Referer-based access control at the edge

Answer

Signed URLs (with expiry and token) or Referer header checking at the CDN edge blocks requests that don't originate from authorized domains.

Question 2

What is the primary security risk addressed by enabling 'Origin Shielding' in a CDN configuration?

Accepted Answer

Prevents attackers from discovering and directly targeting the origin IP address

Answer

By routing all traffic through the CDN and keeping the origin IP hidden, shielding prevents attackers from bypassing the CDN to attack the origin directly.

Question 3

Which CDN performance optimization technique proactively sends resources to the client before they are explicitly requested, based on predicted page dependencies?

Accepted Answer

Server Push (HTTP/2 Push) or Early Hints (103)

Answer

HTTP/2 Server Push and the 103 Early Hints status code allow the server or CDN to push critical resources before the browser has parsed the HTML and discovered them.

Question 4

A CDN's edge node receives a request with the header 'Accept-Encoding: br, gzip'. Which compression format should the CDN prioritize for maximum compression ratio?

Accepted Answer

Brotli (br)

Answer

Brotli (br) typically achieves 15–25% better compression than gzip for text-based assets, reducing transfer size and improving load times.

Question 5

What is a 'Cache Poisoning' attack in the context of CDN security?

Accepted Answer

Injecting malicious content into the CDN cache so it is served to legitimate users

Answer

Cache poisoning tricks the CDN into storing and serving a malicious or altered response, affecting all users who receive the cached content.

(CDN) Content Delivery Network Certification Practice Test

(CDN) Content Delivery Network Certification Practice Test

CDN Security & Performance Optimization 5