* Cross Region Replication is a feature that replicates the data from one bucket to another bucket which could be in a different region.
* It provides asynchronous copying of objects across buckets. Suppose X is a source bucket and Y is a destination bucket. If X wants to copy its objects to Y bucket, then the objects are not copied immediately.
Some points to be remembered for Cross Region Replication
Create two buckets : Create two buckets within AWS Management Console, where one bucket is a source bucket, and other is a destination bucket.
Enable versioning : Cross Region Replication can be implemented only when the versioning of both the buckets is enabled.
Amazon S3 encrypts the data in transit across AWS regions using SSL : It also provides security when data traverse across the different regions.
Already uploaded objects will not be replicated : If any kind of data already exists in the bucket, then that data will not be replicated when you perform the cross region replication.
Use cases of Cross Region Replication
Compliance Requirements : By default, Amazon S3 stores the data across different geographical regions or availability zone to have the availability of data. Sometimes there could be compliance requirements that you want to store the data in some specific region. Cross Region Replication allows you to replicate the data at some specific region to satisfy the requirements.
Minimize Latency : Suppose your customers are in two geographical regions. To minimize latency, you need to maintain the copies of data in AWS region that are geographically closer to your users.
Maintain object copies under different ownership: Regardless of who owns the source bucket, you can tell to Amazon S3 to change the ownership to AWS account user that owns the destination bucket. This is referred to as an owner override option.
