Amazon CloudFront – Content Delivery Network (CDN)

Amazon CloudFront can be used to deliver your entire website, including dynamic, static, streaming, and interactive content using a global network of edge locations. Requests for your content are automatically routed to the nearest edge location, so content is delivered with the best possible performance. Amazon CloudFront is optimized to work with other Amazon Web Services, like Amazon Simple Storage Service (Amazon S3), Amazon Elastic Compute Cloud (Amazon EC2), Amazon Elastic Load Balancing, and Amazon Route 53. Amazon CloudFront also works seamlessly with any non-AWS origin server, which stores the original, definitive versions of your files. Like other Amazon Web Services products, there are no long-term contracts or minimum monthly usage commitments for using Amazon CloudFront – you pay only for as much or as little content as you actually deliver through the content delivery service.

Using a network of edge locations around the world, Amazon CloudFront caches copies of your static content close to viewers, lowering latency when they download your objects and giving you the high, sustained data transfer rates needed to deliver large popular objects to end users at scale. Requests for your dynamic content are carried back to your origin servers running in Amazon Web Services (e.g., Amazon EC2, Elastic Load Balancing) over optimized network paths for a more reliable and consistent experience. These network paths are constantly monitored by Amazon and connections from CloudFront edge locations to the origin are reused to serve your dynamic content from our content delivery network (CDN) with the best possible performance.

A single API call lets you get started distributing content from your Amazon S3 bucket or Amazon EC2 instance or other origin server through the Amazon CloudFront network. Or, interact with Amazon CloudFront through the AWS Management Console’s simple graphical user interface. There is no need to create separate domains for your static and dynamic content. With CloudFront, you can just use the same domain name to point to all of your website content. Any changes you make to your existing configuration take effect across the entire global network within minutes. Plus, since there’s no need to negotiate with a sales person, you can get started quickly and begin delivering your entire website using Amazon CloudFront.

Amazon CloudFront is designed for use with other Amazon Web Services, including Amazon S3, where you can durably store the definitive versions of your static files, and Amazon EC2, where you can run your application server for dynamically generated content. If you are using Amazon S3 or Amazon EC2 as an origin server, data transferred from the origin server to edge locations (Amazon CloudFront “origin fetches”) will be billed at a lower price than Internet data transfer out of Amazon S3 or Amazon EC2. Amazon CloudFront also integrates with Elastic Load Balancing. For instance, you can deploy your web application on Amazon EC2 servers behind Elastic Load Balancing and use Amazon CloudFront to deliver your entire website. Learn more about pricing for all AWS services.

Amazon CloudFront passes on the benefits of Amazon’s scale to you. You pay only for the content that you deliver through the network, without minimum commitments or up-front fees. This applies for any type of content that you deliver – static, dynamic, streaming media, or a web application with any combination of these.

With Amazon CloudFront, you don’t need to worry about maintaining expensive web-server capacity to meet the demand from potential traffic spikes for your content. The service automatically responds as demand increases or decreases without any intervention from you. Amazon CloudFront also uses multiple layers of caching at each edge location and collapses simultaneous requests for the same object before contacting your origin server. These optimizations further help reduce the need to scale your origin infrastructure as your website becomes more popular.

Amazon CloudFront is built using Amazon’s highly reliable infrastructure. The distributed nature of edge locations used by Amazon CloudFront automatically routes end users to the closest available location as required by network conditions. Origin requests from the edge locations to AWS origin servers (e.g., Amazon EC2, Amazon S3, etc.) are carried over network paths that Amazon constantly monitors and optimizes for both availability and performance.

Amazon CloudFront uses a global network of edge locations, located near your end users in the United States, Europe, Asia, and South America and Australia.

There are many great use cases for Amazon CloudFront, including:

A typical website generally contains a mix of static content and dynamic content. Static content includes images or style sheets; dynamic or application generated content includes elements of your site that are personalized to each viewer. A website may also have forms that a user submits to log in, search or post a comment.

You can use a single CloudFront distribution as a content distribution network to deliver your entire website, including both static and dynamic or interactive content to the end users to content uploaded by the end user to the origin. This means that you can continue to use a single domain name (e.g., www.mysite.com) for your entire website without the need to separate your static and dynamic content. Meanwhile, you can still continue to use separate origin servers for different types of content on your website. Amazon CloudFront provides you with granular control for configuring multiple origin servers and caching properties for different URLs on your website. These performance optimizations and functionality can help speed up the download of your entire website which can help lower site abandonment.

Amazon CloudFront can help improve performance of your entire website in the following ways:

• Amazon CloudFront can cache static content at each edge location. This means that your popular static content (e.g., your site’s logo, navigational images, cascading style sheets, JavaScript code, etc.) will be available at a nearby edge location for the browsers to download with low latency and improved performance for viewers. Caching popular static content with Amazon CloudFront also helps you offload requests for such files from your origin sever – CloudFront serves the cached copy when available and only makes a request to your origin server if the edge location receiving the browser’s request does not have a copy of the file.
• Amazon CloudFront proxies requests for dynamic or interactive content (e.g., web forms, comments, login boxes, etc.) back to your origin running in an AWS Region or any other origin. Each of your end users is routed to the edge location closest to them, in terms of internet latency. Then, their requests are carried back to your origin server running in AWS on connections that Amazon monitors and optimizes for performance. Amazon CloudFront also reuses existing connections between the CloudFront edge and the origin server reducing connection setup latency for each origin request. Other connection optimizations are also applied to avoid internet bottlenecks and fully utilize available bandwidth between the edge location and the viewer. This means that Amazon CloudFront can speed-up the delivery of your dynamic content and provide your viewers with a consistent and reliable, yet personalized experience when navigating your web application.
  
• Amazon CloudFront allows content to be uploaded to your origin server. All requests to upload content are proxied by Amazon CloudFront edge locations back to your origin. Amazon CloudFront also applies the same performance benefits to upload requests as those applied to the requests for downloading dynamic content.
• You can also use Amazon CloudFront edge locations to upload large files (up to 20GB per file) to your origin using the PUT HTTP method. Amazon CloudFront can also be used to deliver your API using HTTP methods such as GET, HEAD, POST, PUT, DELETE, PATCH and OPTIONS.
  

Amazon CloudFront is a good choice for software developers who wish to distribute applications, updates or other downloadable software to end users. Amazon CloudFront’s high data transfer rates speed up downloading your applications, improving the customer experience and lowering your costs. Amazon CloudFront also offers lower prices than Amazon S3 at higher usage tiers.

If your application involves rich media – audio or video – that is frequently accessed, you will benefit from Amazon CloudFront’s lower data transfer prices and improved data transfer speeds. Amazon CloudFront offers multiple options for delivering your media files – both pre-recorded media and live media.

• Streaming of pre-recorded media: You can deliver your on-demand media using Adobe’s Real Time Messaging Protocol (RTMP) streaming via Amazon CloudFront. You store the original copy of your media files in Amazon S3 and use Amazon CloudFront for low-latency delivery of your media content. Amazon CloudFront integrates with Amazon S3 so you can configure media streaming by making a simple API call or with a few clicks in the AWS Management Console. You also benefit for the high throughput delivery of your media when using Amazon CloudFront, so you can deliver content in full HD quality to your viewers.
• Progressive download of on-demand media: You can store the original versions of your media content in Amazon S3 and configure an Amazon CloudFront download distribution for progressive download of your video and audio files. Popular media files are cached at the edge to help you scale and give your viewers the best possible performance.
• Delivering live events: If you need to deliver a live event – audio or video – to a global audience, Amazon CloudFront can improve performance and help offload requests to your origin infrastructure by caching your live media for a short period of time and collapsing simultaneous requests for the same media fragment to a smaller number of requests sent to the origin. In addition, Amazon CloudFront’s live HTTP solutions give you the ability to deliver your live event to viewers using different device platforms, including both Flash based and Apple iOS devices.