map

AWS global infrastructure is divided into regions. A region is a locations that hosts a collection of AWS data centers. Each region is a completely separate entity. AWS consumers can choose one or more regions to host their applications.

What to consider when choosing an AWS region?

Following is a list of factors you need to consider when choosing an AWS region.

Services you require

All regions do not offer the same services. When AWS rolls out a new services, it tests it on select region(s) before rolling it out to other regions. All regions offer the core AWS services like EC2, S3, and EBS but if you require a new or more specialized service, it would be a good idea to check with AWS before choosing a region.

Cost of services

Cost of services are region-based. Generally, the services offered in regions across the USA are comparable. That is not the case for regions outside the USA. Either way, it is prudent to find out the cost differences first.

Latency

A common reason for choosing region is proximity to customers. A business whose primary customers are in Europe will be able to provide faster service from a European region than a region in Australia, simply because of the proximity.

Disaster Recovery

A business can replicate its data and applications across different regions. This is expensive but possible.

Security & Compliance

Different countries have different laws around data. The customer might be required to keep the data within the geographic boundaries of the country. This will restrict the choice of region for a customer. It is the responsibility of the AWS customer to comply with local laws.

Availability Zones (AZs)

An availability zone is a collection of data centers connected by low latency connections (dedicated fiber optic lines). Each availability zone has one or more data centers. Each data center within the availability zone has its own dedicated power, power backup, and separate fault tolerances. This is to ensure that if one data center faces an unanticipated interruption, another can ensure service continuity. Each data center is physically and logically different and your data provisioned across multiple availability zones. This ensures high availability and fault tolerance.

Edge Locations

Edge Locations host Content Delivery Network (CDN) and Domain Name Servers (DNS). Many edge location reside outside AWS regions. Edge locations are designed to deliver low latency content. DNS at these location help route the traffic optimally and CDN hosts Amazon CloudFront. CloudFront deliver static cached content. AWS users generally choose multiple edge location to provide faster content delivery to more of its customers. The purpose of an edge location is to improve end-user experience.

Summary

AWS Regions are areas around the world where AWS data centers are located. Availability Zones are one or more discrete data center, each with redundant power, networking, and connectivity. This design of infrastructure provides fault tolerance and redundancy with the need for human intervention. Distributed workload across multiple Availability Zones supports the design for failure cloud architecture design principle.

Questions

Which of the following components of the AWS Global Infrastructure consists of one or more discrete data centers interconnected through low latency links?

Availability Zone. See https://docs.aws.amazon.com/whitepapers/latest/aws-overview/global-infrastructure.html

How many Availability Zones should compute resources be provisioned across to achieve high availability?

A min of two Availability Zones.

By master