CDN Architecture & Components 5

Question 1

What role does an 'Internet Exchange Point' (IXP) play in CDN infrastructure?

Accepted Answer

It is a physical facility where CDNs and ISPs interconnect to exchange traffic directly

Answer

IXPs are neutral facilities enabling CDNs to peer with many ISPs under one roof, reducing latency and transit costs.

Question 2

Which CDN architecture concept describes placing edge servers inside an ISP's own network to eliminate the last-mile hop?

Accepted Answer

Embedded CDN / ISP-hosted PoP (e.g., Netflix Open Connect)

Answer

Embedded CDNs install appliances directly inside ISP networks so content travels zero hops over the public internet to reach subscribers.

Question 3

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

Accepted Answer

Proactively fetching and caching content at edge nodes before user demand arrives

Answer

Cache warming via prefetch pushes anticipated objects to edge nodes ahead of a live event or product launch so the first user request is a cache hit.

Question 4

In CDN health monitoring, what is an 'active health check' as opposed to a 'passive' one?

Accepted Answer

Active checks send synthetic probe requests to origins/edges on a schedule; passive checks infer health from real user traffic failures

Answer

Active health checks proactively test endpoints at intervals, enabling failure detection even when no real users are sending traffic.

Question 5

What is the purpose of a CDN's 'WAF' (Web Application Firewall) component at the edge?

Accepted Answer

To inspect and block malicious HTTP traffic (SQLi, XSS, etc.) before it reaches the origin

Answer

An edge WAF applies rule-based and ML-driven inspection to HTTP requests, filtering attacks at the CDN layer before they can harm the origin.

(CDN) Content Delivery Network Certification Practice Test