Yes, my plan is to move the data to offline servers to perform the checks, probably two to begin with. I would love to avoid both file indexing and storing encryption keys. Which I will try first, that way I can avoid any warrant issues. I don't plan to support incremental backups. I will store multiple volumes, but what's in them is your business. Ideally I would like to rotate out the old volume when a new volume comes in, that's why I am marketing this as archival backup. I suppose I should plan for some multiple set system. Ideally the multiple sets would be onsite and archives would go offsite less frequently. I'm not targeting the backup every week crowd, although I should make an option available.