methods, including those described below. Tape backup for software data long-term archival needs This common method can be used to store data offsite, but data recovery can be a difficult and lengthy process. Tape backup data is only as good as the latest copy stored. Tape backup methods will require a backup device and ongoing storage material. Whole-file and application replication The implementation of this method will require control software and storage capacity for application and data file storage replication typically on the same site. The data is replicated on a different disk partition or separate disk device and can be a scheduled activity for most servers and is implemented more for database-type applications. Hardware and software redundancy This method ensures the highest level of disaster recovery protection for a hardware virtualization solution, by providing duplicate hardware and software replication in two distinct geographic areas. See also Application virtualization Comparison of platform virtualization software Desktop virtualization Dynamic infrastructure Hardware emulation Hyperjacking Instruction set simulator Popek and Goldberg virtualization requirements Physicalization Thin provisioning Virtual appliance Virtualization for aggregation Workspace virtualization References External links An Introduction to Virtualization , by Amit Singh Xen and the Art of Virtualization, ACM, 2003, by a group of authors Linux Virtualization Software