AWS Global Infrastructure

Amazon Web Services operates one of the largest and most sophisticated cloud infrastructures in the world. Understanding how that infrastructure is organised — Regions, Availability Zones, and Edge Locations — is the first step towards building reliable, performant, and compliant applications on AWS.

Why Global Infrastructure Matters

When you deploy an application, its physical location affects three things:

Concern	Why It Matters
Latency	Users closer to your servers get faster responses
Compliance	Some regulations require data to stay within a country or continent
Resilience	Spreading resources across locations protects against localised failures

AWS gives you fine-grained control over where your workloads run, so you can optimise for all three.

Regions

An AWS Region is a geographic area that contains a cluster of data centres. Each Region is a completely independent collection of resources, isolated from every other Region.

Key Facts About Regions

As of early 2026, AWS operates 30+ Regions worldwide, with more announced.
Each Region has a code name such as us-east-1 (N. Virginia), eu-west-2 (London), or ap-southeast-1 (Singapore).
Regions are fully isolated from one another. Data does not automatically replicate between Regions unless you configure it.
Not every AWS service is available in every Region. New services typically launch first in us-east-1.

Choosing a Region

When deciding which Region to use, consider:

Proximity to users — pick the Region closest to your customer base to minimise latency.
Compliance requirements — certain industries or governments require data residency within specific borders.
Service availability — confirm the services you need are available in that Region.
Pricing — costs can vary between Regions. For example, us-east-1 is often the cheapest.

Example: A UK fintech company subject to FCA regulations
might choose eu-west-2 (London) to keep data in the UK,
even if us-east-1 is slightly cheaper.

Availability Zones (AZs)

Each Region is made up of multiple Availability Zones. An AZ is one or more discrete data centres, each with redundant power, networking, and connectivity.

Key Facts About Availability Zones

Most Regions have 3 AZs, though some have more.
AZs are identified by the Region code plus a letter suffix, such as us-east-1a, us-east-1b, us-east-1c.
AZs within a Region are connected by high-bandwidth, low-latency private fibre links.
AZs are physically separated — often by several kilometres — to reduce the risk that a single event (fire, flood, power outage) takes down multiple AZs simultaneously.

Why AZs Matter

AZs are the foundation of high availability on AWS. By distributing your application across multiple AZs, you protect against the failure of a single data centre.

Architecture pattern — Multi-AZ deployment:

  ┌──────────────┐    ┌──────────────┐    ┌──────────────┐
  │   AZ-a       │    │   AZ-b       │    │   AZ-c       │
  │  ┌────────┐  │    │  ┌────────┐  │    │  ┌────────┐  │
  │  │ EC2    │  │    │  │ EC2    │  │    │  │ EC2    │  │
  │  │ inst.  │  │    │  │ inst.  │  │    │  │ inst.  │  │
  │  └────────┘  │    │  └────────┘  │    │  └────────┘  │
  └──────────────┘    └──────────────┘    └──────────────┘
         ▲                   ▲                   ▲
         └───────────────────┼───────────────────┘
                    Elastic Load Balancer

If AZ-a experiences an outage, the load balancer routes traffic to the healthy instances in AZ-b and AZ-c.

AZ Mapping

AWS randomises the mapping of AZ names to physical locations per account. This means us-east-1a in your account might correspond to a different physical data centre than us-east-1a in someone else's account. This prevents everyone from piling into the same physical AZ. You can use AZ IDs (e.g., use1-az1) for consistent cross-account references.

Edge Locations

Edge Locations are AWS data centres positioned in major cities around the world, outside of Regions. They are used to deliver content with low latency to end users.

Services That Use Edge Locations

Service	Purpose
Amazon CloudFront	Content Delivery Network (CDN) — caches static and dynamic content at edge locations close to users
AWS Global Accelerator	Routes traffic through the AWS global network to the optimal endpoint
Amazon Route 53	DNS service that responds from edge locations for fast DNS resolution
AWS WAF	Web Application Firewall that filters traffic at the edge
Lambda@Edge	Run Lambda functions at CloudFront edge locations

Edge Locations vs Regions

Feature	Region	Edge Location
Number	~30+	400+
Purpose	Run full workloads	Cache content, route traffic
Services	All AWS services	CloudFront, Route 53, WAF, Global Accelerator
Data storage	Full persistence	Temporary caches

Regional Edge Caches

Between Regions and Edge Locations, AWS operates Regional Edge Caches. These are larger cache locations that sit between the origin (your Region) and the Edge Locations. They hold content longer than Edge Locations, which helps when content is not popular enough to stay cached at the edge but still needs to be served quickly.

Request flow for CloudFront:

  User → Edge Location → Regional Edge Cache → Origin (S3 / EC2 in Region)
             ↑                    ↑
     Cache hit? Serve.    Cache hit? Serve.

Local Zones and Wavelength Zones

AWS has extended its infrastructure model with additional location types:

Local Zones

Local Zones bring select AWS services closer to large population centres where no full Region exists. They are extensions of a parent Region.

Example: us-east-1-bos-1a is a Local Zone in Boston that extends us-east-1.
Use case: Applications requiring single-digit millisecond latency for users in that city.

Wavelength Zones

Wavelength Zones embed AWS compute and storage at the edge of telecommunications providers' 5G networks.

Use case: Ultra-low-latency applications like real-time gaming, AR/VR, and autonomous vehicle data processing.

AWS Outposts

For organisations that need to run AWS services on-premises, AWS Outposts delivers fully managed AWS infrastructure to your own data centre. Outposts extend a Region to your location, giving you the same APIs, tools, and hardware that AWS uses in its own data centres.

Summary

Concept	What It Is	Typical Count
Region	An isolated geographic area with multiple data centres	30+
Availability Zone	One or more data centres within a Region	3+ per Region
Edge Location	A cache/proxy point in a major city	400+
Regional Edge Cache	A large cache between Edge Locations and Regions	~13
Local Zone	A mini-Region extension near a city	30+
Wavelength Zone	AWS compute at 5G network edges	20+
Outpost	AWS hardware in your data centre	Customer-managed

Understanding AWS global infrastructure helps you make informed decisions about where to deploy your workloads, how to architect for high availability, and how to deliver fast experiences to users worldwide. In the next lesson, we will explore the AWS Management Console — your primary interface for interacting with all of these resources.