To make you transfer safer, Amazon Redshift provides SSL-based connections between the application/client to the Amazon Redshift data warehouse cluster.
Every single block of data is encrypted using the AES-256 as it is written to disk of the cluster storage. This happens at the lowest level, so that every block of data in the disk will be encrypted.
Even the backups you take are encrypted.
If you want to learn more about AWS services then check out this AWS Tutorial page. For more insights about AWS and it's certification, check the AWS Course page.
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