A storage device connectable to a host, said storage device comprising: a descramble module configured to descramble at least a portion of a read command (READ CMD), which includes logical block address information and first meta information (META_H, 300b) provided from a cache table of said host, into first signature information (SGN_H) and first physical address information (PA H) for accessing a flash memory, wherein the first meta information (META_H, 300b) is scrambled data generated by scrambling the first signature information (SGN_H) and the first PA information (PA_H), wherein the first signature information (SGN_H) includes information for determining a validity of the first PA information (PA_H); a compare module configured to compare the first signature information (SGN_H) against second signature information (SGN_D) to thereby determine an equivalency or discrepancy therebetween, wherein the flash memory includes a meta region which stores the second signature information, wherein the meta region includes a first meta region and a second meta region, wherein the first meta region stores first meta region signature information (SGN_D1) on a first LBA set and the second meta region stores second meta region signature information (SGN_D2) on a second LBA set different from the first LBA set, and wherein the second signature information (SGN_D) is equivalent to the first meta region signature information (SGN_D1) or the second meta region signature information (SGN_D2) in accordance with a value of the LBA information; and an access module configured to use the first PA information (PA_H) to access a data region of the memory, upon determination of the equivalency by said compare module. a descramble module configured to descramble at least a portion of a read command (READ CMD), which includes logical block address information and first meta information (META_H, 300b) provided from a cache table of said host, into first signature information (SGN_H) and first physical address information (PA H) for accessing a flash memory, wherein the first meta information (META_H, 300b) is scrambled data generated by scrambling the first signature information (SGN_H) and the first PA information (PA_H), wherein the first signature information (SGN_H) includes information for determining a validity of the first PA information (PA_H); a compare module configured to compare the first signature information (SGN_H) against second signature information (SGN_D) to thereby determine an equivalency or discrepancy therebetween, wherein the flash memory includes a meta region which stores the second signature information, wherein the meta region includes a first meta region and a second meta region, wherein the first meta region stores first meta region signature information (SGN_D1) on a first LBA set and the second meta region stores second meta region signature information (SGN_D2) on a second LBA set different from the first LBA set, and wherein the second signature information (SGN_D) is equivalent to the first meta region signature information (SGN_D1) or the second meta region signature information (SGN_D2) in accordance with a value of the LBA information; and an access module configured to use the first PA information (PA_H) to access a data region of the memory, upon determination of the equivalency by said compare module.