A method for a host device to authenticate a storage device having a plurality of unit storage areas, the method comprising: updating a first sampling function in the host device to vary sampling; obtaining a positional distribution of reference defect areas used for uniquely identifying the storage device; sampling a few of all the unit storage areas of the storage device according to the updated first sampling function; identifying a positional distribution of areas having a physical defect from among the sampled areas; determining similarity between the obtained positional distribution and the identified positional distribution; and authenticating the storage device based on a result of the determination, wherein updating the sampling function includes one of: comparing a version of a second sampling function stored in the storage device and a version of the first sampling function stored in the host device and replacing the first sampling function with the second sampling function when the version of the first sampling function is lower than the version of the second sampling function; comparing a version of a third sampling function stored in a server connected through a network and the version of the first sampling function stored in the host device and replacing the first sampling function with the third sampling function when the version of the first sampling function is lower than the version of the third sampling function; and receiving a sampling function stored in the server connected through the network or the storage device, based on sampling function selection information stored in the storage device, wherein the sampling is performed based on the received sampling function. updating a first sampling function in the host device to vary sampling; obtaining a positional distribution of reference defect areas used for uniquely identifying the storage device; sampling a few of all the unit storage areas of the storage device according to the updated first sampling function; identifying a positional distribution of areas having a physical defect from among the sampled areas; determining similarity between the obtained positional distribution and the identified positional distribution; and authenticating the storage device based on a result of the determination, wherein updating the sampling function includes one of: comparing a version of a second sampling function stored in the storage device and a version of the first sampling function stored in the host device and replacing the first sampling function with the second sampling function when the version of the first sampling function is lower than the version of the second sampling function; comparing a version of a third sampling function stored in a server connected through a network and the version of the first sampling function stored in the host device and replacing the first sampling function with the third sampling function when the version of the first sampling function is lower than the version of the third sampling function; and receiving a sampling function stored in the server connected through the network or the storage device, based on sampling function selection information stored in the storage device, comparing a version of a second sampling function stored in the storage device and a version of the first sampling function stored in the host device and replacing the first sampling function with the second sampling function when the version of the first sampling function is lower than the version of the second sampling function; comparing a version of a third sampling function stored in a server connected through a network and the version of the first sampling function stored in the host device and replacing the first sampling function with the third sampling function when the version of the first sampling function is lower than the version of the third sampling function; and receiving a sampling function stored in the server connected through the network or the storage device, based on sampling function selection information stored in the storage device,