Abstract: In a cartridge key carrier, a data processing system employing an encryption key carrier, and a method for communicating an encryption key, an empty cartridge housing is provided that has a standardized form factor allowing insertion of the cartridge into a standardized magnetic tape drive. A memory chip is permanently attached to the cartridge housing, and has an encryption key stored therein. The memory chip has a chip configuration that allows readout of the encryption key from the memory chip when the housing is inserted into the tape drive.

Abstract: In a data recording system utilizing multiple channels and data blocks wherein the data blocks are read subsequent to being written so as to check for errors, the data blocks are rewritten according to a method to provide for rewriting only the defective data blocks. The blocks may be rewritten on other than their original channels. Channels for rewriting are determined by selecting a channel with a highest current block number so that data is rewritten in a channel which has been able to write and verify the most of its original blocks. Error checking is continued in a channel even after finding of an error in that channel. Data blocks of the frames may be skewed between the channels at a beginning of the frame. A ring counter output is applied to break a deadlock where a block is continously rewritten on a failing channel.

Abstract: In a method for writing data on a data carrier tape, a central region of the tape is positioned adjacent a data recording head, data are supplied to the data recording head, and data are transferred from the data recording head to the tape, beginning at the center region of the tape, while moving the tape along a longitudinal direction of the tape. The tape transport direction can be alternatingly reversed at the opposite ends of the tape so data are recorded successively on adjacent data recording tracks on the tape, with data transfer being inhibited each time the center region of the tape passes by the data recording head. A data carrier tape for implementing the method has a hole pattern in the central region of the tape, which identifies the central region of the tape to allow positioning of the tape at the central region, and to allow recognition of the central region for inhibiting data transfer when the central region of the tape is adjacent the data recording head.

Abstract: A method and apparatus is disclosed for fast access to any logical block on a media not containing logical block addressing. Categorizing marks such as filemarks or setmarks are provided on the tape medium at various points along the medium. The medium is divided up into a plurality of physical blocks. To permit fast access to a logical block on the tape, a connection table in the form of a block map is provided which establishes a relationship between logical blocks and the tapemarks, and defines physical positions of at least some of the tapemarks.