S3 Primary Storage and Bandwidth

Hello, I think this might be a noob question. I want to know if S3 is set up as the primary storage and if data is uploaded, will it go through to the NC server and then to S3 or will it be directly sent to S3? If the former applies then wouldn’t that cause double bandwidth usage?

This.

Nextcloud needs to be able to enforce it’s security model, support sharing, handle encryption (if in use), etc.