CDN Security & Performance Optimization 3

Question 1

When configuring a CDN WAF, what is the key difference between a 'detection mode' and a 'prevention mode' ruleset?

Accepted Answer

Detection mode logs threats without blocking; prevention mode actively blocks

Answer

In detection (monitoring) mode the WAF logs rule matches but passes traffic through; in prevention (blocking) mode matched requests are dropped.

Question 2

A CDN is configured to cache a page for 1 hour (max-age=3600). The origin sends a 'Cache-Control: no-store' header in a subsequent response. What should the CDN do?

Accepted Answer

Immediately purge the cached copy and not cache the new response

Answer

'no-store' instructs all caches including CDNs to neither store nor serve the response from cache; the object must be removed.

Question 3

Which CDN performance feature compresses the TCP slow-start window by reusing existing TCP connections between CDN POPs and the origin?

Accepted Answer

Persistent (keep-alive) connections with origin

Answer

Persistent connections between CDN edge nodes and origin avoid the TCP slow-start penalty on every new object fetch, reducing latency.

Question 4

What does 'cache key normalization' accomplish in CDN configuration?

Accepted Answer

Removes irrelevant query parameters so equivalent URLs share a single cached object

Answer

Cache key normalization strips or sorts query parameters that don't affect content, preventing redundant cache entries for the same effective resource.

Question 5

A financial services company requires that customer PII never be stored on CDN edge nodes. Which CDN configuration achieves this?

Accepted Answer

Set max-age=0 and private cache-control on API responses

Answer

'Cache-Control: private, max-age=0' prevents CDN edge nodes from caching responses, ensuring PII stays only at the origin.

(CDN) Content Delivery Network Certification Practice Test

(CDN) Content Delivery Network Certification Practice Test

CDN Security & Performance Optimization 3