The storage gateway is essentially how AWS is able to sync you cloud storage with your on-prem storage. There are multiple types of storage gateways. First off we have the S3 storage gateway, this allows you to access the gateway via SMB and NFS and it appears like a network drive the gateway itself communicates over HTTPS, the most recently access files are cached in the gateway. This allows you to access your S3 objects on your on-prem and you can even utilize AD as well. Next up we have the volume storage gateway and this gateway connects through S3 over HTTP and you connect to the gateway over iSCSI. This gateway backs up your on-prem data through EBS snapshots. You have two different types of volume gateways, cached where you get low latency access to the most recent data and stored where the entire dataset is on-prem with scheduled backups to S3. Now we have FSx storage gateway this a way for you to connect your FSx file systems to your on-prem infrastructure, this utilizes SMB and NTFS. For archival purposes there’s the tape gateway which allows you to back up your existing tape backups into Amazon S3 as well as glacier for long-term archival. If you prefer you can even get a physical storage gateway appliance instead on using an on-prem VM. The physical appliance supports file, volume, and tape gateways.