- AWS region = a full deployment of AWS services
- some services require region selection (e.g. EC2), some don’t (e.g. IAM, Route53)
- benefits of deploying to multiple regions:
- geographic separation (resilience due to multiple fault domains)
- geopolitical separation (different governance)
- location control (performant due to localized delivery)
- edge location = local distribution point for content delivery
- availability zone = a full set of infrastructure within the region
- helps one region stay available when an incident only affects a part of that geographical region
- connected through high speed low-latency network
- Consider level of service resiliency
- globally resilient (e.g. IAM, Route53): withstand multi-region failure
- region resilient (can withstand): can separately operate across multiple regions, can withstand AZ failure
- AZ resilient: if entire AZ fails, the service fails