CDN Content Distribution & Caching

Question 1

What is the main purpose of content distribution in a CDN?

Accepted Answer

Deliver content from nearby servers

Answer

The main purpose of content distribution in a CDN is to deliver web content to users from servers that are geographically closest to them. By replicating content across a global network of edge servers, CDNs reduce the physical distance data needs to travel. This significantly lowers latency and improves the speed and reliability of content delivery, enhancing the overall user experience.

Question 2

What is caching in the context of CDN?

Accepted Answer

Temporarily storing content near users

Answer

In the context of a CDN, caching involves temporarily storing copies of web content on edge servers located near end-users. When a user requests content, the CDN checks its local cache first. If the content is found, it's delivered quickly from the nearby server, reducing the load on the origin server and significantly speeding up content delivery.

Question 3

Why is cache expiration important?

Accepted Answer

Remove stale content timely

Answer

Cache expiration is crucial for ensuring that users always receive the most up-to-date content from a CDN. It defines how long cached content remains valid before it's considered stale and needs to be re-fetched from the origin server. Timely removal of stale content prevents users from seeing outdated information and ensures that any updates or changes to the original content are reflected promptly.

Question 4

What is a cache hit?

Accepted Answer

Content served from cache

Answer

A cache hit occurs when a user requests content, and that content is successfully found and served directly from the CDN's edge server cache. This is the ideal scenario for a CDN, as it signifies that the content was delivered quickly and efficiently from a nearby location. Cache hits result in faster load times and reduced latency for the end-user.

Question 5

What is a cache miss?

Accepted Answer

Content not found in cache

Answer

A cache miss occurs when a user requests content from a CDN, but the requested content is not found in the local edge server's cache. In this situation, the edge server must then retrieve the content from the origin server. While still delivered through the CDN, a cache miss typically results in slightly higher latency compared to a cache hit, as the content has to travel a greater distance.

(CDN) Content Delivery Network Certification Practice Test

(CDN) Content Delivery Network Certification Practice Test

CDN Content Distribution & Caching