S3 - Storage Gateway

• AWS storage Gateway is a service that connects an on-premise software application with cloud based storage to provide seamless and secure integration between an organization’s on-premise IT environment and AWS’s storage infrastructure. The service enables you to securely store data to the AWS cloud for scalable and cost-effective storage.
• AWS Storage Gateway’s storage appliance is available for download as a virtual machine image that you can install on a host in your datacenter. Storage gateway supports either VMWare ESXi or Microsoft Hyper-V. Once you have installed your gateway and associated it with your AWS account through the activation process, you can use the management console to create the storage option that is right for you.
• File Gateway (NFS): Files are stored as objects on your S3 buckets, accessed through a Network File System (NFS) mount point, Ownership, Permissions, and timestamps are durably stored in S3 in the user metadata of the object associated with the file. Once objects are transferred to S3, they can be managed as native S3 objects, and bucket policies such as versioning, 
• Volumes Gateway (iSCSI): The Volume interface presents your applications with disk volumes using the iSCSI block protocol. Data written to these volumes can be asynchronously backed up as point-in-time snapshots of your volumes, and stored in the cloud as Amazon EBS snapshots. Snapshots are incremental backups that store only changed blocks. All snapshot storage is also compressed to minimize your storage charges.
• Stored Volumes: Lets you store your primary data locally, while asynchronously backing up that data to AWS. Stored volumes provide your on-premise applications with low latency access to their entire dataset, while providing durable, off site backup. You can create storage volumes and mount them as iSCSI devices from your on-premise application servers. Data written to your to your stored volumes is stored on your on-premise hardware. This data is asynchronously backed up to to Amazon S3 in the form of Amazon EBS snapshots. 1GB to 16TB in size for stored volumes.
• Cached Volumes: Let you use S3 as your primary data storage while retaining frequently accessed data locally in your storage gateway. Cached volumes minimize the requirement to scale your on-premise storage infrastructure, while still providing your applications with low latency access to their frequently accessed data. You can create storage volumes upto 32TB in size and attach to them as iSCSI devices from your on-premise application servers. Your gateway stores data the you write to these volumes in Amazon S3 and retains recently read data in your on-premise storage gateway’s cache and upload buffer storage. 1GB to 32TB in size of cached volumes.
• Tape Gateway (VTL): Tape Gateway provides a durable and cost effective way to archive your data in the AWS cloud. The VTL interface it provides let’s you leverage your existing tape-based backup application infrastructure to store data on virtual tape cartridges that you create on your tape gateway. Each tape gateway is preconfigured with media changer and tape devices, which are available to your existing client backup applications as iSCSI devices. You add tape cartridges as you need to archive your data. Supported by NetBackup, Backup Exec, Veeam etc.
• File Gateway - For flat files stored directly in S3.
• Volume Gateway - 
• Stored Volumes - Entire dataset is stored on site and is asynchronously backed up on S3
• Cached Volumes - Entire dataset is stored on S4 and the most frequently accessed data is stored on site.
• Gateway Virtual Tape Library (VTL) - Used for backup and uses popular backup applications like: NetBackup, Backup Exec, Veeam etc.