AWS Global Infrastructure Overview

The components

In this lesson, we will go over some of the components of the AWS global infrastructure. These are the most important ones you need to know at this stage.

Region

A region is a geographical area with at least two availability zones in it, and each region is isolated from other AWS Regions. There are about 23 of them around the world at the moment, which changes all the time. So by the time you read this, you may find that there are 24 or 25 regions.

Availability zones

Then, we have availability zones (AZ). A region will have at least two availability zones within it; however, sometimes, they have five or more. An availability zone comprises one or more data centers, and these are physically separated from other availability zones. That being said, they’re connected with low latency, highly available, and high bandwidth links. You can deploy your resources within a region but into separate availability zones for high availability and redundancy. This means that if there’s an outage on one availability zone, your resources in the other ones won’t be affected. You’ve got networking connectivity between all of the AZs as well.

Edge caches and regional edge caches

Edge locations and regional edge caches are both parts of the CloudFront network. CloudFront is all about caching content. It caches content at locations around the world. These locations are closer to your users, so the idea is to reduce latency when accessing cached content. There are two concepts here: the edge location and the regional edge cache with the edge location. There are about 176 edge locations at the moment around the world. The regional edge caches are about 11, and they’re just a bit bigger. They have a bigger cache bandwidth, and they are set between the services that you have in AWS and the edge locations themselves.

Global network

This is what makes up AWS. Of course, there’s a global network, and this is a private global network that AWS manages. It is highly available, low latency, and interconnects every data center availability zone and AWS Region.

The table below summarizes the points discussed above.

Name	Description
Region	A geographical area with 2 or more AZs isolated from other AWS Regions
Availability Zone (AZ)	One or more data centers that are physically separate and isolated from other AZs
Edge Location	A location with a cache of content that can be delivered at low latency to users; used by CloudFront
Regional Edge Cache	Also part of the CloudFront network; these are larger caches that sit between AWS services and Edge Locations
Global Network	Highly available, low-latency private global network interconnecting every data center, AZ, and AWS Region

An overview

Let’s look at the diagram below. Now that you have a bit more information about regions, you can see three regions in this diagram: one is in the eastern U.S., one is in the western EU West, and the other is in Southeast Asia Pacific. These are actually Norfolk, Virginia, Dublin in Ireland, and Sydney in Australia. In this diagram, each region has three availability zones. In reality, they might have more or less, but they’ll have at least two, and they might have five or more.