Designing highly performant solutions on AWS is one of the key metrics of the well-architected framework. All AWS services seek to boost performance to some extent. In this article, however, we are going to focus our attention and energy on Amazon CloudFront and AWS Global Accelerator, services provided by AWS to help businesses and application developers enhance the performance of their applications and services. By leveraging the power and capabilities of CloudFront and Global Accelerator, developers and businesses can optimize their infrastructure and deliver high-performance applications to users.

Without any further ado, let's get started. We are going to start by exploring the features and capabilities of CloudFront, then we will delve into AWS Global Accelerator.

Amazon CloudFront

CloudFront is a powerful content delivery network (CDN) service provided by AWS that gives businesses and web application developers an easy and cost-effective way to distribute static and dynamic content with low latency and high data transfer speeds. It acts as a global network of servers strategically located around the world, allowing you to deliver content to your users efficiently. Like other AWS services, CloudFront is a self-service, pay-per-use offering, requiring no long-term commitments or minimum fees.

CloudFront operates through a global network of edge locations (geographically dispersed data centres) strategically positioned around the world. When a user requests content, CloudFront serves it from the nearest edge location, reducing the distance and network latency. This ensures fast delivery and a smooth user experience. As of the time of writing of this article, CloudFront makes use of over 300 edge locations in different places around the world. With CloudFront, you can distribute any content that can be sent using the HTTP or WebSocket protocols, such as images, videos, web pages, and APIs, to end users across the globe. It caches your content at edge locations, reducing the round-trip time and improving overall performance.

CloudFront provides several advanced features to optimize content delivery. It supports custom SSL certificates, allowing you to secure your content with HTTPS. It also offers compression, content minification, and automatic content delivery optimizations to enhance performance and reduce bandwidth usage. Another key feature of CloudFront is its integration with other AWS services. You can seamlessly integrate CloudFront with Amazon S3, EC2, Lambda, and other AWS services, enabling you to deliver dynamic content and handle complex workflows efficiently. Additionally, CloudFront integrates with AWS WAF (Web Application Firewall) to protect against common web-based attacks such as SQL injections and Cross-site scripting.

Now let's examine some features that will help you leverage the power of CloudFront to build highly-performant applications. These features include CloudFront Geo Restriction, Origins, Price Classes, and Cache invalidation.

CloudFront Origins

In CloudFront, an origin is simply the source of the content that CloudFront delivers to end users. CloudFront supports various types of origins, giving you the freedom to choose the origin option that best fits your requirements and use case. Below are the types of origins supported by CloudFront:

1. Amazon S3 Bucket: You can use an S3 bucket as an origin for CloudFront. This allows you to distribute static content stored in S3, such as images, videos, CSS, and JavaScript files. CloudFront can retrieve and cache this content at edge locations, improving delivery performance.

2. Elastic Load Balancer: If you have an application running behind an Elastic Load Balancer, you can configure the ELB as an origin for CloudFront. CloudFront will distribute user requests across the instances behind the load balancer, improving scalability and availability.

3. Custom HTTP Server: CloudFront supports using custom HTTP servers or web applications as origins. You can specify the domain name or IP address of your server as the origin. CloudFront will forward user requests to your server, retrieve the content, and cache it at edge locations.

4. Lambda Function: CloudFront allows you to use AWS Lambda functions as origins. This enables you to dynamically generate or modify content before it is delivered to end users. Lambda@Edge functions can be triggered at CloudFront edge locations, providing powerful customization options.

5. MediaPackage Channel: CloudFront can integrate with AWS Elemental MediaPackage, which is a video origination and packaging service. By using a MediaPackage channel as an origin, you can deliver live or on-demand video content through CloudFront.

6. Regional API Gateway: You can also use an AWS Regional API Gateway as an origin for CloudFront. This allows you to cache and deliver responses from API Gateway, improving the performance of your API requests.

It is important to note that for every origin that you add to a CloudFront distribution, you can assign a backup origin that can be used to automatically serve your traffic if the primary origin is unavailable. By employing different types of origins, CloudFront provides flexibility in serving content from various sources. You can combine origins, configure caching behaviour, and customize delivery options to meet the specific needs of your application or website.

CloudFront Geo Restriction

This is a feature of CloudFront that gives you granular control over the geographic distribution of your content. It allows you to specify which countries or geographic regions can access your content, and which ones are denied access. This feature is particularly useful when you have content that needs to comply with regional regulations, licensing agreements, or content distribution rights.

CloudFront Geo Restriction operates based on the IP addresses of the viewers. It uses the Geo-IP database (a comprehensive database that maps IP addresses to specific geographic locations) to determine the geographic location of the viewer and then applies the specified access restrictions accordingly. With CloudFront Geo Restriction, you can choose between two options: Whitelist and Blacklist.

1. Whitelist: With this option, you can create a list of countries or geographic regions that are allowed to access your content. Requests coming from outside the specified whitelist will be denied. This is useful when you want to restrict access to specific regions and ensure that only authorized viewers can access your content.

2. Blacklist: In contrast to the whitelist option, the blacklist option allows you to specify a list of countries or geographic regions that are denied access to your content. Requests coming from the specified blacklist will be blocked, while all other regions will have access. This is helpful when you want to block access from specific regions due to legal restrictions, content distribution rights, or other business requirements.

By leveraging CloudFront Geo Restriction, you can ensure that your content is accessible only to the intended audience while adhering to regulatory and licensing constraints. This feature provides an additional layer of security and control, allowing you to deliver your content seamlessly to the desired geographic regions while keeping it inaccessible to unauthorized viewers, enabling you to meet compliance requirements, honour content distribution agreements, and enhance the overall performance and security of your application.

CloudFront Price Classes

They refer to the different pricing tiers or regions offered by CloudFront, which determine the cost of delivering content through the CloudFront CDN. The Price Classes are designed to optimize cost and performance by offering different levels of coverage and availability across geographic regions. There are three price classes available:

1. Price Class All (Global) — This is the highest price class and provides the broadest coverage across all CloudFront edge locations worldwide. It ensures that your content is delivered from the most geographically distributed edge locations, maximizing global performance and availability. However, it also comes with a higher cost compared to other price classes.

2. Price Class 200 (Most Popular) — This price class offers a more cost-effective option while still providing widespread coverage. It includes a subset of the global edge locations, focusing on the most frequently accessed regions. Price Class 200 strikes a balance between performance and cost, making it a popular choice for many applications.

3. Price Class 100 (Least Expensive) — This is the most cost-efficient price class, suitable for applications with specific regional or localized user bases. It includes a smaller subset of edge locations, primarily serving the region where your content is predominantly accessed. While it offers reduced coverage, it still provides satisfactory performance for localized applications and helps lower overall delivery costs.

By selecting the appropriate Price Class for your application, you can optimize the cost-performance balance based on your specific needs. If your content is globally distributed and accessed from various regions, Price Class All may be the ideal choice. For applications with more localized audiences, Price Class 200 or 100 can help you minimize costs while ensuring satisfactory performance within specific regions. It's important to note that the specific edge locations available in each price class may change over time as Amazon expands its network. Therefore, it's recommended to review the CloudFront documentation or pricing page for the most up-to-date information on the available edge locations and their coverage within each price class.

CloudFront Cache Invalidation

It is often said that the hardest things to do in the world of computing are naming and cache invalidation. That statement highlights the challenges associated with these two aspects of software development. CloudFront handles the heavy lifting of cache invalidation by providing a few mechanisms that allow you to control the caching behaviour and efficiently invalidate or update the cached content. It performs cache invalidation by clearing outdated content from its edge locations. Here is how it is done:

When you make changes to your website or application, you want those changes to be visible to your users immediately. However, cached copies of your content may still exist in CloudFront's edge locations. To invalidate the cache and ensure that users receive the latest content, you can request a cache invalidation. Think of cache invalidation as a way to tell CloudFront, "Hey buddy, something has changed! Please clear the old version of the content and fetch the new one." You can specify the specific files or directories that need to be invalidated. CloudFront then updates its cache by removing outdated content and fetching the latest version from your origin server. Once you submit a cache invalidation request, it may take some time for the invalidation to propagate to all the edge locations. However, as the invalidation progresses, users will start receiving the updated content from CloudFront's edge locations, ensuring a fast and consistent experience.

Cache invalidation is an essential feature that makes sure your users always see the most recent version of your website or application. It helps you maintain control over your content and deliver timely updates to your audience.

AWS Global Accelerator

Global Accelerator is a networking service that helps you improve the availability and performance of the applications that you offer to your global users. It is easy to set up, configure, and manage. Global Accelerator provides static IP addresses that provide a fixed entry point to your applications and eliminate the complexity of managing specific IP addresses for different AWS Regions and Availability Zones.

Global Accelerator operates by utilizing the AWS global network infrastructure, allowing you to improve the performance of your applications by lowering first-byte latency (the round trip time for a packet to go from a client to your endpoint and back again) and jitter (the variation of latency) and increasing throughput (amount of data transferred in a second) as compared to the public internet. Here is how it works:

When you set up Global Accelerator, you are assigned a pair of anycast IP addresses. These IP addresses are advertised globally, and they attract traffic from users requesting access to your applications. Anycast IP addresses are unique in that they can be announced by multiple edge locations simultaneously. When a user sends a request to the anycast IP, the request is automatically routed to the nearest edge location based on network proximity. This routing is handled by the Border Gateway Protocol (BGP), which directs the traffic to the most optimal edge location. These anycast IPs simplify configuration in that instead of managing multiple IP addresses or manually routing traffic, you can simply point your DNS records to the anycast IP addresses assigned by Global Accelerator. The routing is handled automatically, optimizing application delivery without complex setups.

It is important to remember that in addition to performance improvements, Global Accelerator offers built-in DDoS protection through integration with AWS Shield. This helps safeguard your applications against malicious traffic and ensures high availability even during DDoS attacks. To end this section on Global Accelerator, here are some common use cases of the powerful service:

• Global Accelerator can improve the performance and availability of your website or application for users around the world. It directs user traffic to the nearest AWS edge location, reducing latency and improving response times.

• If you have a multi-region architecture for your application, Global Accelerator can route traffic to the closest healthy endpoint across regions. It helps distribute the load and ensures optimal performance across multiple regions.

• Global Accelerator can be used to facilitate disaster recovery by redirecting traffic to an alternate endpoint in case of a failure. This ensures fast and automated failover to minimize downtime and ensure business continuity.

• For gaming and media streaming applications, it helps deliver low-latency, high-quality experiences to users worldwide. It optimizes the delivery of real-time interactive content by routing traffic to the most optimal edge location.

Closing Remarks

In this article, we have examined CloudFront and Global Accelerator, your dynamic duo for supercharging application performance. By harnessing the global network of edge locations provided by CloudFront, you can deliver content with lightning-fast speed and impress your users with an exceptional user experience. Combine that with the smart routing and optimization capabilities of Global Accelerator, and you have a powerful toolkit for achieving optimal performance and reliability. So, go ahead and embrace CloudFront and Global Accelerator to take your applications to the next level. Your users will thank you for it, and your business will reap the rewards of a highly performant digital presence. Kudos to you for going on this CloudFront/Global Accelerator journey with me, if you have any questions, I'll be waiting for them in the comments section.