Amazon CloudFront Key Features
AWS Global Infrastructure
The AWS Cloud spans 117 Availability Zones within 37 Geographic Regions, with announced plans for 13 more Availability Zones and 4 more AWS Regions in New Zealand, the Kingdom of Saudi Arabia, Chile, and the AWS European Sovereign Cloud.
Global Edge Network
Reliable, low latency and high throughput network connectivity
Network Connectivity and Backbone
Amazon CloudFront peers with thousands of Tier 1/2/3 telecom carriers globally, is well connected with all major access networks for optimal performance, and has hundreds of terabits of deployed capacity. CloudFront edge locations are seamlessly connected to AWS Regions through the fully redundant AWS network backbone. This backbone is comprised of multiple 400GbE parallel fibers across the globe and interfaces with tens of thousands of networks for improved origin fetches and dynamic content acceleration.
Amazon CloudFront has three types of infrastructure to securely deliver content with high performance to end users:
CloudFront Regional Edge Caches (RECs) are situated within AWS Regions, between your applications’ web server and CloudFront Points of Presence (POPs) and embedded Points of Presence. CloudFront has 13 RECs globally.
CloudFront Points of Presence are situated within the AWS network and peer with internet service provider (ISP) networks. CloudFront has 700+ POPs in 100+ cities across 50+ countries.
CloudFront embedded Points of Presence are situated within internet service provider (ISP) networks, closest to end viewers. In addition to CloudFront POPs, there are 900+ embedded POPs across 300+ cities in North America, Europe, and Asia.
Security
Availability
Origin Shield
Web applications often need to contend with spikes in traffic during peak periods of activity. By using Amazon CloudFront, the volume of application origin requests is automatically reduced. Content is stored in CloudFront’s edge and regional caches and only fetched from origins when needed. The load on application origins can be further reduced by using Origin Shield to enable a centralized caching layer. Origin Shield optimizes cache hit ratios and collapses requests across regions leading to as few as one origin request per object. This reduced traffic to your origins helps increase the availability of your applications.
Enabling redundancy for origins
CloudFront supports multiple origins for backend architecture redundancy. CloudFront’s native origin failover capability automatically serves content from a backup origin when the primary origin is unavailable. The origins set up with origin failover can be any combination of AWS origins like EC2 instances, Amazon S3 buckets, or Media Services, or non-AWS origins like an on-premises HTTP server. Additionally, you can implement advanced origin failover capabilities with CloudFront and Lambda@Edge.
Edge computing
CloudFront Functions
Amazon CloudFront offers programmable and secure edge CDN computing capabilities through CloudFront Functions and AWS Lambda@Edge. CloudFront Functions is ideal for high scale and latency sensitive operations like HTTP header manipulations, URL rewrites/redirects, and cache-key normalizations. These types of short running, lightweight operations support traffic that is often unpredictable and spiky. For example, you can use CloudFront Functions to redirect requests to language specific versions of your site based on the Accept-Language header of the incoming request. Because these functions execute at all of CloudFront’s edge locations, they can scale instantly to millions of requests per second with minimal latency overhead, typically under one millisecond. You can also utilize CloudFront KeyValueStore, a global, low-latency, key value data store to store and retrieve lookup data from within CloudFront Functions. CloudFront KeyValueStore makes CloudFront Functions more customizable by allowing independent data updates.
Lambda@Edge
AWS Lambda@Edge is a general-purpose serverless compute feature that supports a wide range of computing needs and customizations. Lambda@Edge is best suited for computationally intensive operations. This could be computations that take longer to complete (several milliseconds to seconds), take dependencies on external 3rd party libraries, require integrations with other AWS services (e.g., S3, DynamoDB), or need networks calls for data processing. Some of the popular advanced use cases include HLS streaming manifest manipulation, integrations with 3rd party authorization and bot detection services, server-side rendering (SSR) of single-page apps (SPA) at the edge and more.
Real-time metrics and logging
Real-time metrics
Amazon CloudFront is integrated with Amazon CloudWatch, and automatically publishes six operational metrics per distribution, which are displayed in a set of graphs in the CloudFront console. Additional, granular metrics are available with simple click on the console or via API.
Standard and real-time logging
CloudFront provides two ways to log the requests delivered from your distributions: Standard logs and Real-time logs. Standard logs are delivered to the Amazon S3 bucket of your choice (log records are delivered within minutes of a viewer request). When enabled, CloudFront will automatically publish detailed log information in a W3C extended format into an Amazon S3 bucket that you specify. CloudFront real-time logs are delivered to the data stream of your choice in Amazon Kinesis Data Streams (log records are delivered within seconds of a viewer request). You can choose the sampling rate for your real-time logs—that is, the percentage of requests for which you want to receive real-time log records.
DevOps friendly
Continuous deployment
Continuous deployment with CloudFront gives you a high level of deployment safety. You can now deploy two separate but identical environments—blue and green, and enable simple integration into your continuous integration and delivery (CI/CD) pipelines with the ability to roll out releases gradually without any domain name system (DNS) changes. It ensures that your viewer gets a consistent experience through session stickiness by binding the viewer session to the same environment. Additionally, you can compare the performance of your changes by monitoring standard and real-time logs and quickly revert to the previous configuration when a change negatively impacts a service. Typical use cases for this feature include checking for backward compatibility, post-deployment verification, and validating new features with a smaller group of viewers.