Patent ID: 7934105

Claim:
A tape drive for storing data to a tape cartridge, the tape drive being operable to: receive, from a host in communication with the tape drive, data to be stored as a plurality of records, each record having an indeterminate size; encrypt at the tape drive a first portion of the records using a first encryption key and encrypt at the tape drive a second portion of the records using a second encryption key, each of the first portion and the second portion comprising an integral number of records; store the encrypted records to the tape cartridge as a plurality of data blocks, each data block having a predetermined size and comprising one or more encrypted records, wherein records in a respective data block are encrypted using only a respective one of the first and second encryption keys; receive, from the host, the second encryption key; in response to receiving the second encryption key, pad a current partial chunk of data of the first portion so the partial chunk of data has a predetermined size and so each of the records is encrypted with a single encryption key; replace the first encryption key with the second encryption key; encrypt records to the tape cartridge with the second encryption key.