Abstract: The IBM TS7700 Series is the latest in the line of tape virtualization products that has revolutionized the way mainframe customers utilize their tape resources. Security of the information stored on the internal disk subsystem used to virtualize tape has become important to many customers. The TS7700 internally uses a disk subsystem to store or cache virtual tape volumes. The IBM TS7700 disk subsystem models have been enhanced to support encryption. This white paper describes the use of data encryption on these disk subsystems when used in the TS7700 Virtualization Engine. The document has been updated to include disk encryption on the TS7760 offering.