CDN Content Distribution & Caching 2

Question 1

Which cache eviction policy removes the item that has not been accessed for the longest period of time?

Accepted Answer

Least Recently Used (LRU)

Answer

LRU evicts the item whose last access time is the oldest, making it ideal for workloads with temporal locality.

Question 2

A CDN edge node receives a request for a resource with 'Cache-Control: no-store'. What must the CDN do?

Accepted Answer

Not store any part of the request or response

Answer

'no-store' is the strictest directive, instructing the CDN to never persist any part of the transaction.

Question 3

What is 'cache warming' in the context of CDN operations?

Accepted Answer

Pre-populating edge caches with content before user requests arrive

Answer

Cache warming proactively pushes content to edge nodes to avoid cold-start latency spikes when traffic begins.

Question 4

Which HTTP header does a CDN use to indicate that a cached response is stale but still being served while a background revalidation occurs?

Accepted Answer

Warning: 110

Answer

HTTP Warning code 110 ('Response is Stale') signals that the CDN is serving a stale cached response.

Question 5

A media company serves video segments of varying popularity. Which caching strategy best handles a long-tail content distribution?

Accepted Answer

Use tiered caching with a large regional cache behind edge nodes

Answer

Tiered caching allows long-tail content to be fetched once to a regional parent cache and then served to multiple edge nodes.

(CDN) Content Delivery Network Certification Practice Test