The VTL was invented because, at the time (2012ish), none of the largest enterprise backup solutions had a good S3 interface and none supported Glacier. After talking with the backup software vendors (Spectrum, Tivoli, Symantec, Commvault, etc) it became clear that adding another backup target wasn't something we (AWS) could get them to prioritize, for perfectly reasonable reasons. We could (and did) apply pressure via our shared customers, even then they estimated it would take years.
The fastest way to enable large enterprise access to S3 and Glacier for backups was to meet them where they were. We did this by virtualizing a tape library.
You did such a great job they still try and steer people this route. I've multiple times mentioned "you know we don't need to emulate tape drives any more"
This is a fantastic example of how broken the patent system is.
This is not an invention it’s a good implementation of a well understood problem.
It is also priced ridiculously - it is at least an order of magnitude more expensive than operating a physical library and remote physical storage that is beyond cyber threat by virtue of it being disconnected.
You did such a good job, that when I worked on Glacier (2013-2016), our interactions with the team running VTL was already pretty minimal. It was one of the least problematical things that interacted with Glacier.
Some of the solutions that external vendors produced were nightmarish and left customers up the creek without a paddle in a disturbing number of situations.
The fastest way to enable large enterprise access to S3 and Glacier for backups was to meet them where they were. We did this by virtualizing a tape library.
Background: I'm one of the original inventors - https://image-ppubs.uspto.gov/dirsearch-public/print/downloa.... I am no longer with AWS.