AWS Global Infrastructure

Core Components of the AWS Global Infrastructure

Definition: An AWS Region is a physical, geographic location in the world where AWS clusters data centers.
Isolation: Each AWS Region is designed to be completely isolated from the other AWS Regions. This provides the greatest possible fault tolerance and stability.
Resource Scoping: Most AWS services are scoped to a specific Region. This means when you launch a resource like an EC2 instance or an S3 bucket, you do so in a selected Region.
Considerations for Choosing a Region:
- Latency: Choose a Region close to your users to minimize latency.
- Cost: Costs can vary between different AWS Regions.
- Service Availability: Not all AWS services are available in every Region.
- Compliance: Data sovereignty and compliance requirements may dictate which Region you must use.

Definition: An Availability Zone (AZ) is one or more discrete data centers with redundant power, networking, and connectivity within an AWS Region.
Relationship to Regions: Each Region consists of multiple, isolated AZs (typically 3 or more).
Fault Tolerance: AZs are physically separated by a meaningful distance (many kilometers) from each other, yet close enough to have low-latency (single-digit millisecond) network connectivity. This setup protects applications from a single data center failure.
High Availability: The best practice for high availability is to architect applications to run across at least two AZs within a Region. If one AZ fails, the application can failover to another AZ without interruption.

Definition: Edge Locations are a worldwide network of data centers that AWS uses for content delivery and low-latency services. They are more numerous than Regions.
Primary Use Cases:
- Amazon CloudFront: To cache content closer to end-users, which reduces latency and improves performance for website and application content delivery. When a user requests content, it's served from the nearest Edge Location for the fastest possible speed.
- Amazon Route 53: To provide a highly available and scalable Domain Name System (DNS) service. Route 53 uses Edge Locations to respond to DNS queries quickly from anywhere in the world.
Key Distinction: Edge Locations are not used to run your primary infrastructure like EC2 instances or databases; they are used specifically for caching and DNS resolution.

Definition: Regional Edge Caches are a type of caching location that sits between your origin server (e.g., an S3 bucket or EC2 instance) and the global Edge Locations.
Purpose: They have a larger cache-width than individual Edge Locations. When content is not popular enough to remain in a local Edge Location, it is moved to the larger Regional Edge Cache. This helps keep more of your content closer to your users without having to fetch it from the origin server, improving performance.
How it Works: The data flow is: Origin Server -> Regional Edge Cache -> Edge Location -> User.

Definition: An extension of an AWS Region that places compute, storage, and other select services closer to large population, industry, and IT centers where no Region exists today.
Use Case: Ideal for latency-sensitive applications like real-time gaming, media and entertainment content creation, and live video streaming.

Definition: A fully managed service that extends AWS infrastructure, services, APIs, and tools to virtually any customer data center, co-location space, or on-premises facility.
Use Case: For workloads that require extremely low latency to on-premises systems or for local data processing needs. It allows you to run AWS services on-premises for a truly consistent hybrid experience.