AWS global infrastructure (for example, Availability Zones, AWS Regions)

The AWS global infrastructure consists of several physical and logical components that are deliberately distributed across the globe to optimize service delivery. Here’s a look at the major components:

AWS Regions

Regions are distinct geographical locations around the world where AWS clusters its data centers. Each AWS Region consists of multiple, isolated, and physically separate Availability Zones (AZs) within a geographic area. Because of the separation and isolation of these AZs, the failure of one does not significantly impact the resilience of the infrastructure.

Examples of AWS Regions: us-east-1 (N. Virginia), eu-west-1 (Ireland), ap-southeast-2 (Sydney)

Availability Zones (AZs)

Availability Zones are one or more discrete data centers with redundant power, networking, and connectivity housed within a Region. Each AZ is engineered to be isolated from failures of other AZs, providing businesses with the options to operate production applications and databases that are more highly available, fault-tolerant, and scalable than would be possible from a single data center.

Example: Within the us-east-1 region, there could be several Availability Zones, such as us-east-1a, us-east-1b, us-east-1c, etc.

Edge Locations and Regional Edge Caches

Edge Locations are endpoints for AWS which are used for caching content. They are typically located in major cities and highly populated areas to provide end-users with lower latency by caching copies of popular files closer to user locations.

Regional Edge Caches are larger than edge locations and help to cache objects at locations that are not quite large enough to have their own AWS Region or full-sized data center.

Designing Architectures with AWS Global Infrastructure

When preparing for the AWS Certified Solutions Architect – Associate exam, it’s important to learn how to effectively use these components to build resilient and scalable systems.

Fault Tolerance and High Availability

To ensure fault tolerance and high availability, an application should be deployed across multiple Availability Zones. This allows an application to remain available if one AZ becomes unavailable.

• Example Scenario: A multi-tier web application is designed to be highly available by deploying it across three Availability Zones within the same region. Web servers are placed in an Auto Scaling Group and a Multi-AZ RDS database instance is used to ensure the application remains operational even if one AZ fails.

Latency Optimization

Content Delivery Network (CDN) services like Amazon CloudFront can be used in conjunction with Edge Locations to reduce latency. By caching content at the edge closest to the end-users, the time to deliver content is significantly reduced.

• Example Scenario: A media company serving a global audience can use Amazon CloudFront to cache video content at Edge Locations around the world, minimizing the latency experienced by viewers in different locations.

Region Selection Strategy

The selection of AWS Regions for deploying applications can be based on factors like compliance with data sovereignty laws, proximity to end-users, services available within a Region, and pricing.

• Example Scenario: A European enterprise may choose the eu-central-1 (Frankfurt) region for their core infrastructure to comply with GDPR requirements, while still utilizing edge locations across the world for content delivery.

Conclusion

The AWS global infrastructure offers a scalable and resilient foundation for designing and running applications in the cloud. By leveraging Regions, AZs, and Edge Locations, you can create architectures that are resilient to failure, low in latency, and optimized for a global audience. Understanding these concepts and how they interplay is crucial for aspirants of the AWS Certified Solutions Architect – Associate certification.