Amazon Web Services (AWS) started as an internal infrastructure used by Amazon. Over time, the company realised other organisations could benefit from the same infrastructure, so they began offering it as a service.
The first AWS service launched was SQS (Simple Queue Service), which allowed applications to communicate asynchronously using message queues.
Today AWS provides hundreds of services used by companies around the world.
AWS Global Infrastructure
AWS operates in multiple Regions around the world.
A Region is a geographical area that contains multiple Availability Zones (AZs).
Each Availability Zone is a cluster of data centres connected by high-speed, low-latency networks.
Availability Zones are designed to be isolated from each other so that failures or disasters affecting one zone do not impact the others.
Key points:
- Each region contains multiple Availability Zones
- The number of AZs per region varies between 3 and 6
- Each Availability Zone contains one or more data centres
- AZs have redundant power, networking, and connectivity
- AZs are connected by ultra-low latency networks
This design allows applications to be deployed across multiple AZs for high availability and fault tolerance.
Choosing an AWS Region
When deploying infrastructure on AWS, the region you choose can depend on several factors:
- Compliance – some regulations require data to stay within certain geographic locations
- Latency – choosing a region closer to users reduces network latency
- Available services – some AWS services are not available in all regions
- Pricing – AWS pricing may vary slightly between regions
Global vs Regional Services
Some AWS services are global, meaning they are not tied to a specific region.
Examples include:
- AWS Identity and Access Management (IAM)
- Amazon Route 53
- Amazon CloudFront
- AWS WAF
Most other AWS services are regional services, meaning they are deployed within a specific region.