Virtual tape isn't necessarily the entire answer to backup. It still doesn't address the requirements of off-site storage and disaster recovery, but it can be used with a hierarchical storage management system in which data is moved to slower and increasingly less expensive storage media as it is used less. Virtual tape may also be included as part of a storage-area network, with a single virtual tape server managing less-used or archived data for many networked computers.

Kay is a Computerworld contributing writer in Worcester, Mass. You can contact him at russkay@charter.net.