AWS 5.6: CloudFront

Question 1

What problem does CloudFront solve in network communication?

Answer 1

It reduces network latency and performance issues caused by long distances between users and the origin server.

Question 2

What is an origin server in the context of CloudFront?

Answer 2

The origin server is where the original version of the data is stored (e.g., images, videos, web content).

Question 3

Why does distance between the user and origin server affect performance?

Answer 3

Because data must travel across multiple networks, increasing latency, which slows down loading and user experience.

Question 4

What is a Content Delivery Network (CDN)?

Answer 4

A distributed network of servers that deliver content to users from locations closer to them.

Question 5

How does CloudFront improve performance compared to traditional delivery?

Answer 5

By delivering content through edge locations close to users instead of always fetching from the origin server.

Question 6

What are edge locations in CloudFront?

Answer 6

Global data centres that cache content closer to users for faster delivery.

Question 7

Explain how CloudFront uses Route 53 in request routing.

Answer 7

Route 53 uses geolocation routing to direct the user to the closest edge location, improving speed.

Question 8

Describe the full request flow when a user accesses content using CloudFront.

Answer 8

User sends request

Route 53 finds closest edge location

Request goes to edge location

If cached → content returned immediately

If not cached → edge fetches from origin server

Content stored (cached) at edge

Returned to user

Question 9

What happens when the requested content is NOT in the edge cache?

Answer 9

CloudFront retrieves it from the origin server, then caches it at the edge for future requests.

Question 10

What is caching in CloudFront?

Answer 10

Storing copies of data at edge locations so it can be served quickly without contacting the origin server again.

Question 11

What happens when cached data becomes stale?

Answer 11

It is removed from the cache to make space for updated content.

Question 12

What is TTL (Time to Live) and why is it important?

Answer 12

TTL defines how long content stays in the cache before it expires.

It controls:
* Freshness of data
* Cache efficiency

Question 13

Why is CloudFront considered cost-effective compared to traditional CDNs?

Answer 13

Because:
* No contracts
* Pay-as-you-go pricing
* No minimum fees

Question 14

How does CloudFront improve user experience?

Answer 14

By reducing:
* Latency
* Load times
* Network delays

Question 15

A user in Japan accesses a website hosted in the US. Without CloudFront, what happens vs with CloudFront?

Answer 15

Without CloudFront:
* Request travels long distance → high latency

With CloudFront:
* Request goes to nearest edge (Japan) → faster response

Question 16

A website has many images and videos. Why is CloudFront especially useful here?

Answer 16

Because it efficiently delivers high-density content (media files) with reduced latency.

Question 17

Why does CloudFront not always contact the origin server?

Answer 17

Because it uses cached content at edge locations, reducing load on the origin.

Question 18

If TTL is set very low, what impact does this have?

Answer 18

More frequent origin requests
* Less caching efficiency
* More up-to-date content

Question 19

If TTL is set very high, what impact does this have?

Answer 19

• Better performance (more caching)
• Risk of outdated/stale content

Question 20

Which combination correctly explains CloudFront performance improvement?

Answer 20

• Edge locations
• Caching
• Reduced latency
• Route 53 routing to nearest edge