Patent ID: 8037309

Claim:
A portable data storage device comprising: a non-volatile memory to store data; an interface section to receive a command from and transmit the data to a host, wherein the interface section includes a USB plug integral with the portable data storage device and a USB interface device; a master control unit to transfer the data from the non-volatile memory, wherein the master control unit is a programmable integrated circuit that operates based upon software downloaded from the non-volatile memory; and an integrated circuit to generate at least one key, wherein the portable data storage device is arranged, upon receiving the command from the host requesting the data stored in the non-volatile memory, the data stored prior to receiving the command, to generate the at least one key, to encrypt the generated key using a secret key that is permanently stored in the portable storage device, and to transmit the encrypted key and the requested data stored in the non-volatile memory to the host using the interface section, wherein the secret key is permanently stored within the portable storage device prior to the generating at least one key, and wherein the portable data storage device is further arranged to receive from the host a digital signature that is generated using the at least one generated key and the requested data transmitted to the host from the portable storage device, and the portable storage device is further arranged to use the received digital signature to verify that the requested data has been correctly received by the host.