Abstract:
A data storage and retrieval system includes a head carriage unit adapted for rotational motion and having multiple heads disposed at a working surface. The system also includes a tape drive unit configured to move a tape media past the working surface of the head carriage unit, the tape media having a width approximately equal to a width of the working surface. As the head carriage unit rotates and the tape moves past the working surface, a first head is configured to write a data track to the tape and a second head is configured to thereafter read the data track, where data read by the second head is for use in verifying data integrity and performing error correction.
Abstract:
During a read-after-write operation on magnetic tape, a first SCO is formed which includes two encoded processed user data units and is one of T SCOs in a first SCO set. The user data units are each one of T user data units in first and second user data unit sets, respectively, within the first SCO set. The first SCO set is written to the magnetic tape and is immediately read. When an error is detected in one of the user data units, a second SCO is formed to include the first user data unit and, only if an error is not detected in a user data unit in the other user data unit set, to not include the other user data unit, the second SCO being one of T SCOs in a second SCO set. Then, the second SCO set is rewritten to a later position on the tape later.
Abstract:
Strategy and methodology by which the various error sources are taken into account and methods applied to compensate substantially entirely for such errors and/or diminish the effect of such errors.
Abstract:
Replacement data for updating data recorded on an information storage medium is recorded in an area for logical overwrite (LOW) replacement; replacement data for replacing a defect generated on the medium is recorded in an area for defect replacement; and, if a defect is generated in an original block recorded in a predetermined area of the medium during a read-modify-write (RMW) process for a LOW for at least partial data of an original block, a replacement block replacing the original block is recorded in the area for LOW replacement and a defect list (DFL) entry including location information of the original block and location information of the replacement block is generated to indicate the replacement state.
Abstract:
The recording method of the present invention includes the steps of: receiving a write instruction which specifies at least a logical sector in which data is to be written; determining whether the logical sector corresponds to a recorded physical sector or an unrecorded physical sector (S1411); when it is determined that the logical sector corresponds to an unrecorded physical sector, writing the data into the unrecorded physical sector (S1412), determining whether a verification of the data which has been written into a physical sector is successful (S1413), if the verification of the data that has been written is not successful, writing the data into an unrecorded physical sector (S1414), generating a remapping table including remapping information which remaps an original address of the physical sector corresponding to the logical sector to a remapping address of the selected physical sector (S1415), and writing the remapping table on the write-once disc.
Abstract:
A write once disc allowing management of a data area, a method of managing the data area of the write once disc, an apparatus recording data on the write once disc, an apparatus and method of reproducing data from a write once disc. The write once disc, includes a lead-in zone, a data area, and a lead-out zone. The write once disc includes a predetermined area storing area allocation information which indicates whether at least one section of the data area is allocated for disc defect management. In the disc and method, area allocation information specifying a structure of the data area is recorded on the disc, thus allowing a recording/reproducing apparatus to recognize the data area structure. Therefore, allocating areas, such as a spare area, for disc defect management other than an area for storing user data, to the data area is possible. The allocation of the areas for disc defect management to the data area enables effective use of the write once disc.
Abstract:
A high density write-once recording medium allowing defect management, and a method and apparatus for managing defects are provided. According to the high density writing-once recording medium, data is written to the recording medium in tracks or clusters, the written data is verified, and if a defect is found a defective portion is skipped and data corresponding to the defective portion and the following written data are rewritten on a next available recording location. The defect management method using slipping replacement is applied to the high density write-once recording medium in which defects are found, thereby allowing continued recording by slipping defects found in the recording medium and further increasing the reliability of the recording medium.