Amazon Cloudfront FAQ

If you're not aware of Amazon Cloudfront Service, I'd suggest you to read What is Amazon Cloudfront? before going through the FAQ.

  • With CloudFront, your files are delivered to end-users using a global network of edge locations.

  • Amazon CloudFront employs a global network of edge locations and regional edge caches that cache copies of your content close to your viewers. Amazon CloudFront ensures that end-user requests are served by the closest edge location. As a result, viewer requests travel a short distance, improving performance for your viewers.

  • Amazon CloudFront is a good choice for distribution of frequently accessed static content that benefits from edge delivery—like popular website images, videos, media files or software downloads.

  • The regional edge caches are located between your origin web server and the global edge locations that serve content directly to your viewers.

  • By default, if no cache control header is set, each edge location checks for an updated version of your file whenever it receives a request more than 24 hours after the previous time it checked the origin for changes to that file. This is called the “expiration period.” You can set this expiration period as short as 0 seconds, or as long as you’d like, by setting the cache control headers on your files in your origin.

  • Amazon CloudFront does not cache the responses to POST, PUT, DELETE, and PATCH requests – these requests are proxied back to the origin server. You may enable caching for the responses to OPTIONS requests.

  • WebSocket is a real-time communication protocol that provides bidirectional communication between a client and a server over a long-held TCP connection. By using a persistent open connection, the client and the server can send real-time data to each other without the client having to frequently reinitiate connections checking for new data to exchange. WebSocket connections are often used in chat applications, collaboration platforms, multiplayer games, and financial trading platforms.

  • Field-Level Encryption is a feature of CloudFront that allows you to securely upload user-submitted data such as credit card numbers to your origin servers.

  • You can integrate your CloudFront distribution with AWS WAF, a web application firewall that helps protect web applications from attacks by allowing you to configure rules based on IP addresses, HTTP headers, and custom URI strings. Using these rules, AWS WAF can block, allow, or monitor (count) web requests for your web application.

  • Yes, CloudFront can automatically compress your text or binary data. To use the feature, simply specify in your cache behavior settings that you would like CloudFront to compress objects automatically and ensure that your client adds Accept-Encoding: gzip in the request header (most modern web browsers do this by default).

  • Lambda@Edge allows you to run code at global AWS edge locations without provisioning or managing servers, responding to end users at the lowest network latency. You just upload your Node.js code to AWS Lambda and configure your function to be triggered in response to Amazon CloudFront requests (i.e., when a viewer request lands, when a request is forwarded to or received back from the origin, and right before responding back to the end user). The code is then ready to execute at every AWS edge location when a request for content is received, and scales with the volume of requests across CloudFront edge locations.

Reference: Amazon Cloudfront FAQs