We can use Cross Region Replication Amazon S3 to make copies of an object

across buckets in different AWS Regions. This copying takes place

automatically and in an asynchronous mode.

We have to add replication configuration on our source bucket in S3 to make

use of Cross Region Replication. It will create exact replicas of the objects

from source bucket to destination buckets in different regions.

Some of the main use cases of Cross Region Replication are as follows:

1. Compliance: Some times there are laws/regulatory requirements that

ask for storing data at farther geographic locations. This kind of

compliance can be achieved by using AWS Regions that are spread

across the world.

2. Failover: At times, we want to minimize the probability of system

failure due to complete blackout in a region. We can use CrossRegion Replication in such a scenario.

3. Latency: In case we are serving multiple geographies, it makes sense

to replicate objects in the geographical Regions that are closer to end

customer. This helps in reducing the latency

https://aws.amazon.com/s3/features/replication/#:~:text=You%20can%20use%20CRR%20to,protect%20data%20from%20accidental%20deletion.