Is Cognito High Available service by default?

Question

I'm writing a report about high availability in my application. Today we use Cognito as authentication service.

In AWS documentation I found this page about resilience in Cognito

https://docs.aws.amazon.com/cognito/latest/developerguide/disaster-recovery-resiliency.html

But I want to understand this really means that Cognito is high available? In case in a failure of an availability zone, Cognito still works?

Answer 1

In the Regional Availability paragraph of the Amazon Cognito developer guide it is stated that:

Amazon Cognito is available in multiple AWS Regions worldwide. In each Region, Amazon Cognito is distributed across multiple Availability Zones. These Availability Zones are physically isolated from each other, but are united by private, low-latency, high-throughput, and highly redundant network connections. These Availability Zones enable AWS to provide services, including Amazon Cognito, with very high levels of availability and redundancy, while also minimizing latency.

Additionally, the current version (published March 6, 2019) of the Amazon Cognito SLA (Service License Agreement) has defined an uptime of "three nines" for any given month:

AWS will use commercially reasonable efforts to make Cognito available with a Monthly Uptime Percentage for each AWS region, during any monthly billing cycle, of at least 99.9% [...]. In the event Cognito does not meet the Service Commitment, you will be eligible to receive a Service Credit as described [...]