Patent ID: 7266203

Claim:
An information system configured to limit access to encrypted data stored on a storage medium, comprising: a first storing unit storing in an original encryption device having an encryption circuit encrypting/decrypting data, device-specific information for identifying the original encryption device, and one or more pieces of key information for encrypting/decrypting data stored on the medium; a second storing unit storing in the medium encryption circuit specification information specifying the encryption device to be used when encrypting/decrypting data; a detecting unit detecting a match between the encryption circuit specification information and device-specific information of device used to access encrypted data, when the encrypted data is accessed; and a restoring unit pre-storing device-specific information of the original encryption device and the key information at a predetermined site accessible through a network, and the restoring unit restoring at least the key information to a new encryption device from the predetermined site when the original encryption device becomes unavailable to allow only the new encryption device having the restored key information to access the encrypted data.