Amazon CloudFront & Content Delivery
7 questions found
What is Amazon CloudFront and how does it improve website performance?
Beginner
Amazon CloudFront is a global content delivery network service that caches copies of your website content, such as images, videos, and web pages, at edge locations physically closer to your users around the world, so requests are served from a nearby location instead of traveling all the way back to your origin server, reducing latency significantly.
aws cloudfront create-distribution --origin-domain-name mybucket.s3.amazonaws.com
Real-world example
A global news website uses CloudFront so that a reader in Tokyo loads images and articles from a nearby edge location instead of waiting for content to travel from a server located in the United States.
Common follow-ups: What is an edge location and how many does AWS operate?;How does CloudFront decide which edge location serves a specific user?
S3 & Storage;VPC & Networking
What types of origins can CloudFront distribute content from?
Beginner
CloudFront can pull content from many types of origins including Amazon S3 buckets for static files, Elastic Load Balancers or EC2 instances for dynamic web applications, and even servers outside of AWS entirely, meaning you are not limited to only distributing content that already lives inside AWS.
aws cloudfront create-distribution --origin-domain-name myapp.example.com
Real-world example
An online store uses CloudFront with two different origins, an S3 bucket for its product images and an Application Load Balancer for its dynamic checkout pages, all delivered through a single CloudFront distribution.
Common follow-ups: Can a single CloudFront distribution have multiple origins?;How do you configure CloudFront to route different paths to different origins?
Elastic Load Balancing (ALB
NLB & CLB);EC2 & Compute
How does caching work in CloudFront, and how do you control how long content stays cached?
Intermediate
CloudFront caches content at edge locations based on cache behaviors you configure, including a time to live value that controls how long an object is kept before CloudFront checks the origin again for a fresh copy, and you can also control caching using HTTP headers like Cache Control sent directly from your origin server.
aws cloudfront create-invalidation --distribution-id ABC123 --paths '/images/*'
Real-world example
An e commerce site sets a long cache duration for rarely changing product images but a very short cache duration for its frequently updated pricing page, balancing performance with data freshness.
Common follow-ups: What is a cache invalidation and when should you use one?;How do query strings affect CloudFront caching behavior?
Amazon API Gateway;S3 & Storage
How do you secure content delivered through CloudFront so only authorized users can access it?
Intermediate
CloudFront supports signed URLs and signed cookies that let you generate time limited, cryptographically signed links to private content, as well as Origin Access Control which ensures that an S3 origin can only be accessed through CloudFront and never directly, preventing users from bypassing your distribution entirely.
aws cloudfront sign --url https://example.com/video.mp4 --key-pair-id ABC123 --private-key file://private_key.pem --date-less-than 2026-12-31
Real-world example
A video streaming platform generates signed URLs that expire after a few hours for each customer's video, ensuring that a shared link cannot be used indefinitely by unauthorized viewers.
Common follow-ups: What is the difference between signed URLs and signed cookies?;How does Origin Access Control differ from the older Origin Access Identity?
IAM;S3 & Storage
What role does CloudFront play in protecting applications from security threats?
Intermediate
CloudFront integrates directly with AWS WAF, letting you attach web application firewall rules that block common attacks such as SQL injection and cross site scripting before they ever reach your origin server, and it also supports HTTPS enforcement with free SSL certificates through AWS Certificate Manager, keeping data encrypted in transit.
aws cloudfront update-distribution --id ABC123 --distribution-config file://config-with-waf.json
Real-world example
A financial services company attaches AWS WAF rules to its CloudFront distribution to automatically block malicious traffic patterns before they reach its backend servers, reducing the load and risk on its origin infrastructure.
Common follow-ups: How do you attach a WAF web ACL to a CloudFront distribution?;What is the difference between CloudFront's built in DDoS protection and AWS Shield?
AWS WAF & Shield;AWS Certificate Manager (ACM)
How do Lambda at Edge and CloudFront Functions extend the capabilities of a CloudFront distribution?
Advanced
Lambda at Edge lets you run more complex custom code, written in Node.js or Python, at CloudFront edge locations to modify requests and responses, such as personalizing content or performing authentication checks, while CloudFront Functions offer a lighter weight, faster, and cheaper option written in JavaScript for simpler tasks like URL rewrites or header manipulation, both running much closer to the user than your origin server.
function handler(event) {
var request = event.request;
request.uri = request.uri.replace('/old-path/', '/new-path/');
return request;
}
Real-world example
A media company uses a CloudFront Function to automatically redirect users requesting an outdated URL structure to the correct new page, without ever needing to involve the origin server in that decision.
Common follow-ups: When should you use Lambda at Edge instead of CloudFront Functions?;What are the execution time limits for each option?
Lambda & Serverless;Amazon API Gateway
How does CloudFront support multi region high availability and failover for an application?
Advanced
CloudFront can be configured with origin failover, where you designate a primary and a secondary origin, so if the primary origin becomes unavailable or returns errors, CloudFront automatically routes requests to the secondary origin instead, providing seamless failover without requiring any changes on the client side.
aws cloudfront create-distribution --distribution-config file://config-with-origin-group.json
Real-world example
A global SaaS company configures CloudFront origin failover between its primary region's load balancer and a secondary region's load balancer, ensuring customers experience no downtime even if an entire AWS region has issues.
Common follow-ups: What criteria trigger a CloudFront failover to the secondary origin?;How does this compare to using Route 53 health checks for failover?
Amazon Route 53 & DNS Management;AWS Backup & Disaster Recovery