In this post, I will share some basic information about AWS Regions and AZs.
Regions
AWS hosts its data centers across various geographical regions. As of March 2020, AWS seems to have 22 regions as shown in the picture below:
Picture reference: https://aws.amazon.com/about-aws/global-infrastructure/?p=ngi&loc=1
Picture reference: https://docs.aws.amazon.com/documentdb/latest/developerguide/regions-and-azs.html
Picture reference: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-regions-availability-zones.html
Each region is completely independent from each other. The data stored in most AWS services is not synchronized across the regions.
An end user can choose a region based on proximity(to reduce network latency), SLAs (vary by region), cost, services offered, compliance needs.
Availability Zones (AZs)
To cater to high availability needs of hosted services, an AWS Region has inter-connected data centers at multiple locations called AZs (Availability Zones) connected with low-latency links.
The number of available AZs (usually:3) in each region can be found by pointing to the region of interest as shown below:
Local Zone
A Local Zone helps an end user to run latency sensitive applications (such as real time gaming, Machine learning applications etc) closer to the user's target audience. A Local Zone is connected to the parent region via high bandwidth & low latency private network.
A Local Zone is different from an AZ in that a Local Zone offers limited services such as VPC, ELB, EC2, EBS, etc. For other services such as S3, Aurora etc over the AWS private network.
References:
