Physical Storage Media(Cont.) Tape storage non-volatile,used primarily for backup(to recover from disk failure),and for archival data sequential-access-much slower than disk very high capacity(40 to 300 GB tapes available) tape can be removed from drive storage costs much cheaper than disk,but drives are expensive Tape jukeboxes available for storing massive amounts of data hundreds of terabytes(1 terabyte 109 bytes)to even a petabyte(1 petabyte=1012 bytes) Database System Concepts-5th Edition,Oct 23,2005. 11.8 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 5 11.8 ©Silberschatz, Korth and Sudarshan th Edition, Oct 23, 2005. Physical Storage Media (Cont.) Tape storage non-volatile, used primarily for backup (to recover from disk failure), and for archival data sequential-access – much slower than disk very high capacity (40 to 300 GB tapes available) tape can be removed from drive  storage costs much cheaper than disk, but drives are expensive Tape jukeboxes available for storing massive amounts of data  hundreds of terabytes (1 terabyte = 109 bytes) to even a petabyte (1 petabyte = 1012 bytes)