123 results about "Write once read many" patented technology

This invention provides a specified retention date within a data set that is locked against deletion or modification within a WORM storage implementation. This retention date scheme does not utilize any proprietary application program interfaces (APIs) or protocols, but rather, employs native functionality within conventional file (or other data containers, data sets or block-based logical unit numbers) properties available in commonly used operating systems. In an illustrative embodiment, the retention date / time is calculated by querying the file's last-modified time prior to commit, adding the retention period to this value and thereby deriving a retention date after which the file can be released from WORM. Prior to commit, the computed retention date is stored in the file's “last access time” property / attribute field, or another metadata field that remains permanently associated with the file and that, in being used for retention date, does not interfere with file management in a WORM state. Since this field is not utilized in a WORM context, it can be adapted to store this date. Once stored, the retention date in this field is locked against modification. Where extension (never reduction) of a retention period is desired, the last access time field be updated, wherein the new retention period is added to the existing last access time value to derive a new, later retention date for the file. Upon expiry of the retention date, the system allows deletion of the expired WORM file / data set.

Disclosed is a method for storing digital information for storage in an adversarial setting in which trusted hardware enforces digital information compliance with data storage mandates. Secure storage overhead is minimized by identifying sparsely accessing the trusted hardware based on data retention cycles. Data retention assurances are provided for information stored by a Write-Once Read-Many (WORM) storage system.

Disclosed are a system, an apparatus, a method and an article of manufacture to provide for writing WORM (write once read many) data to a data storage device. A WORM pointer memory is used for maintaining an inventory of LBAs (logical block addresses) where WORM data may be written on the data storage media of the data storage device. The WORM pointer memory is a tamper proof memory device to maintain data integrity with respect to WORM data.

A write-once-read-many (WORM) storage system that employs large-capacity and relatively inexpensive disks in connection with a file system on a file server is provided. The file system contains most or all of the required WORM functionality so as to impose a minimal footprint on client applications, client operating systems and open protocols if desired. The system is organized around WORM storage volumes that contain files that, when committed to WORM storage, cannot be deleted or modified. Any file path or directory tree structure used to identify the file within the WORM volume is locked and cannot be deleted. In one embodiment, the administrator creates a WORM volume, capable of storing designated WORM files. The client then creates an appropriate WORM file using the appropriate protocol semantics. The file is written to the volume and committed by transitioning the file attributes from a not-read-only to a read-only state. The file system recognizes the persistently stored WORM attribute of any file in a WORM volume as WORM file. Henceforth, any attempt to modify the file attributes, write to the file, or delete the file, by clients, administrators or other entities is rejected and a request denied message is returned to the attempting party

A multilayer optical memory of WORM (write-once-read-many) type has photosensitive layers with fluorescent reading. The disc contains a transparent substrate and multiple information layers spatially divided from one another by polymer layers and assembled using adhesive layers. Information is stored in a photosensitive substance within spiral grooves. The photosensitive substance can be formed as a continuous layer or as discrete grooves on a non-photosensitive background. Various compositions for the photosensitive substance allow recording in by changing fluorescence bleaching or emitting, with threshold-type recording.

This invention provides a specified retention date within a data set that is locked against deletion or modification within a WORM storage implementation. This retention date scheme does not utilize any proprietary application program interfaces (APIs) or protocols, but rather, employs native functionality within conventional file (or other data containers, data sets or block-based logical unit numbers) properties available in commonly used operating systems. In an illustrative embodiment, the retention date / time is calculated by querying the file's last-modified time prior to commit, adding the retention period to this value and thereby deriving a retention date after which the file can be released from WORM. Prior to commit, the computed retention date is stored in the file's “last access time” property / attribute field, or another metadata field that remains permanently associated with the file and that, in being used for retention date, does not interfere with file management in a WORM state. Since this field is not utilized in a WORM context, it can be adapted to store this date. Once stored, the retention date in this field is locked against modification. Where extension (never reduction) of a retention period is desired, the last access time field be updated, wherein the new retention period is added to the existing last access time value to derive a new, later retention date for the file. Upon expiry of the retention date, the system allows deletion of the expired WORM file / data set.

Disclosed are a system and method for writing WORM data to a data storage device by use of a WORM LBA indicator. A WORM memory is used to maintain an inventory of logical block addresses (LBAs) where WORM data is written on the data storage media of the data storage device. The WORM memory is a tamper proof memory device to maintain data integrity with respect to WORM data. Before writing any data to the disk the WORM memory for each LBA where data will be written is examined to determine if writing is allowed at the LBA. If writing is allowed, the data is written, otherwise no data is written.

A wide area distributed storage system checks for erasion of WORM (Write-Once Read-Many) files. A first management server (100a) acquires from second disk equipment (200b) a storage location of a file which corresponds to the file stored on first disk equipment (200a), of which a storage period has expired, and queries a management server (100b) about a storage period of the file whose storage location has been acquired. The queried file management server refers to a file table and indicates existence or non-existence of the file on the second disk equipment and whether the storage period of the file has expired or not. The system avoids unintended deletion of files by querying a plurality of file management servers about whether a file with an expired retention period should be set as a deletable object.

A polycarbonate composition excellent in both antistatic property and coloring matter coatability containing (a) a polycarbonate obtained by an ester exchange process, and (b) a compound having a molecular weight of from 300 to 8,000 and having any of ester bond, carbonate bond, amide bond and urethane bond in its molecule and an aromatic hydrocarbon group substituted by at least one alkyl group at the molecular end thereof, a write once read many optical disc substrate and a write once read many optical disc using the same and a process for the production of a write once read many optical disc are described.

Provided is a compound semiconductor nanoparticle that exhibits circularly polarized luminescence characteristics. CdS prepared inside a core of ferritin, which is a cage-like protein, exhibits a high circularly polarized luminescence (CPL). A wavelength of the circularly polarized luminescence (CPL) can be controlled by laser irradiation, thereby enabling utilization of the compound semiconductor nanoparticle in the field of bionanotechnology, for example, in creating a WORM (Write-Once Read-Many times) memory. As the cage-like protein, which is a protein with a cavity formed therein, a protein belonging to the ferritin protein family, such as apoferritin, or a recombinant thereof can be used.

A file system in a storage system allows a user to designate data as write-once read-many (WORM) data. The WORM data are stored in a first set of storage media of the storage system. Signature data are generated from the WORM data. Using the signature data, the integrity of the WORM data can be verified.

For recording information at high density even at blue-laser wavelengths, a write-once-read-many optical recording medium includes a first inorganic thin film and at least one of a second inorganic thin film and an organic thin film, in which the first inorganic thin film contains at least “R” and “O,” wherein “R” is at least one selected from Y, Bi, In, Mo, V and lanthanum series elements; and “O” is oxygen atom, and the second inorganic thin film and the organic thin film are capable of suppressing at least one of deformation and breakage of the first inorganic thin film and receiving the change of state of the first inorganic thin film.

It is an object of the present invention to provide a semiconductor device mounted with a memory which can be driven in the ranges of a current value and a voltage value which can be generated from a wireless signal. It is another object to provide a write-once read-many memory into which data can be written anytime after manufacture of a semiconductor device. An antenna, an antifuse-type ROM, and a driver circuit are formed over a substrate having an insulating surface. A stacked layer of a silicon film and a germanium film is interposed between a pair of electrodes included in the antifuse-type ROM. The antifuse-type ROM having this stacked layer can reduce fluctuation in writing voltage.

A disk recording medium which can implement a recording method having a high degree of reliability for additional information is disclosed. The disk recording medium has a recording and reproduction region into and from which first data can be recorded and reproduced in accordance with a rewritable or write-once-read-many recording method and from which second data recorded in the form of wobbling of a groove can be reproduced. The second data includes address information and additional information. The additional information of the second data is coded in accordance with a first error correction method, and the coded additional information and the address information are recorded in a state coded in accordance with a second error correction method.

An object is to provide a semiconductor device mounted with memory which can be driven in the ranges of a current value and a voltage value which can be generated from a wireless signal. Another object is to provide write-once read-many memory to which data can be written anytime after manufacture of a semiconductor device. An antenna, antifuse-type ROM, and a driver circuit are formed over an insulating substrate. Of a pair of electrodes included in the antifuse-type ROM, the other of the pair of the electrodes is also formed through the same step and of the same material as a source electrode and a drain electrode of a transistor included in the driver circuit.

The main object of the present invention is to provide a recording medium which makes high densification of information possible, particularly a write-once-read-many optical recording medium having good recording signal characteristics to a wide range of recording powers. The present invention is one to accomplish the above object by providing a recording medium having a recording layer, whereby recording is carried out by heating the recording layer, characterized in that the recording layer contains a substance A which decomposes at a temperature which the recording layer reaches when heated for recording, and a substance B which does not undergo a chemical reaction or phase change at a temperature which the recording layer reaches when heated for recording.

According to one aspect and example, a method is provided for handling write protected storage devices. The method includes generating a read signal from a portion of a magnetic storage medium and determining if a modulation pattern is present in the read signal, the modulation pattern associated with an identification mark comprising a pattern of indicia associated with a recording layer of the magnetic storage medium. The identification mark indicates that the storage medium is a write protected storage device (e.g., a write-once-read-many “WORM” storage device or the like). If the storage medium is write protected, a media drive is restricted from write operations to the storage medium according to the particular write protected scheme, e.g., WORM, write append only, or the like.

A storage system, method and system for protecting data stored on a volume of the storage system. The storage system includes a storage media upon which the volume is represented, a disk controller which controls the storage system, and a write once read many (WORM) configuration table having a plurality of entries which indicate by use of a next write pointer which of a plurality of areas of the volume is write protected. Alternatively, the entries of the WORM configuration table could indicate write protected areas of the volume each being defined by use of a beginning offset and an ending offset.

A write-only-read-many type optical recording medium includes a substrate, an organic material layer having a light absorption function that is sufficient for recording in the recording / reproduction wavelength range, the organic material layer being situated on the substrate, and a reflection layer being situated on the organic material layer. The recording medium is configured to have a Low-to-High recording property and record with a laser having a wavelength that is no greater than 500 nm.

A modified disk drive that includes means for selectively and permanently disabling the write mode of the hard disk drive by the use of programmable read only memory (PROM) circuitry is provided. One method of use employs selectively blowing a PROM fuse in the arm electronics of the hard disk drive to prevent further writing to a respective disk surface in the hard disk drive. A second method of use employs selectively blowing a PROM fuse in processor-accessible memory, to prevent further writing to a section of logical block addresses (LBAs) corresponding to a respective set of data sectors in the hard disk drive.

A write once read many magnetic tape system has a tape cartridge housing a length of magnetic tape adapted to record and store electronic data, and an electronic memory device. A tape drive receives the tape and reads the memory device. The drive is operable only in a write once read many mode in response to information read from the memory device.

Image formation via photoinduced fluorescence changes in a polymeric medium with two-photon fluorescence readout of a multi-layer structure. Fluorophore-containing polymers, possessing one or more basic functional groups, underwent protonation in the presence of a photoinduced acid generator upon exposure to a broad-band UV light source or fast-pulsed red to near-IR laser irradiation. Solution studies demonstrated formation of monoprotonated and diprotonated species upon irradiation, each resulting in distinctly different absorption and fluorescence properties. The fluorescence of the original, neutral, fluorophore was reduced upon monoprotonation, leading to a concomitant increase in fluorescence at longer wavelengths due to the monoprotonated form, the basis for multichannel data readout. Experiments in polymer films demonstrate the changes in fluorescence properties of the photosensitive polymer compositions and polymers can be employed for a high storage density, write-once read-many (WORM) data storage medium with two-photon fluorescence readout. Two-channel, two-photon fluorescence imaging provided both “positive” and “negative” image readout capability.

A write-once-read-many (WORM) storage system that employs large-capacity and relatively inexpensive disks in connection with a file system on a file server is provided. The file system contains most or all of the required WORM functionality so as to impose a minimal footprint on client applications, client operating systems and open protocols if desired. The system is organized around WORM storage volumes that contain files that, when committed to WORM storage, cannot be deleted or modified. Any file path or directory tree structure used to identify the file within the WORM volume is locked and cannot be deleted. In one embodiment, the administrator creates a WORM volume, capable of storing designated WORM files. The client then creates an appropriate WORM file using the appropriate protocol semantics. The file is written to the volume and committed by transitioning the file attributes from a not-read-only to a read-only state. The- file system recognizes the persistently stored WORM attribute of any file in a WORM volume as WORM file. Henceforth, any attempt to modify the file attributes, write to the file, or delete the file, by clients, administrators or other entities is rejected and a request denied message is returned to the attempting party

A write-once read-many information recording medium is provided, which is capable of easily searching for a latest DDS and a latest defect list. At least one disc management working area is sequentially allocated in a predetermined direction on the write-once read-many information recording medium of the present invention. The latest defect list and the latest DDS are provided in a recorded disc management working area neighboring a border between the recorded disc management working area and an unrecorded disc management working area, where the latest defect list precedes the latest DDS in the predetermined direction.

The invention discloses a distributed file system access method and a platform. The method comprises the steps of obtaining a write-in request of a client; judging whether the file size of a file to be written in corresponding to the write-in request is smaller than a threshold value of a preset file or not; if yes, determining the file type of the file to be written in as a small file, caching the file to be written in into a distributed redis cluster. The distributed redis cluster is adopted as a cache pool, the client writes in the file from a storage cluster of a rear-end magnetic disk, and the file is read from the redis cluster. It can be seen that for write-once read-many-times, on the condition that the file is small and is not deleted, during write-in, the small file is cached into the redis cluster, when read, the small file is read directly from the redis cluster, and the file reading delay is shortened; the redis cluster and the storage cluster of the rear-end magnetic disk are isolated, the redis cluster reading behavior cannot affect the write-in behavior of the rear-end magnetic disk, the pressure of the rear-end magnetic disk is reduced, and the file system performance is improved.

In a storage area network (SAN) including a storage device accessible by a remote client, a method is provided. The SAN is configured to allow input / output (I / O) data transport over the SAN between the remote client and the storage device. The method includes establishing a write once read many (WORM) server in the SAN between the storage device and the remote client. Data is received at the WORM server from the remote client. The method further includes appending a digitally signed timestamp to the data, specifying a plurality of locations, and sending the data and the timestamp to the storage device. The data is sent as a series of data over the SAN such that the series of data is written to the storage device at the specified plurality of locations. Future writing of data to the specified plurality of locations is prevented.

A storage device capable of selectively rendering certain data irretrievable is disclosed. The storage device includes Write Once Read Many (WORM) storage medium, a key generator, an encrypted write component, an erasable storage medium and a key deleter. The WORM storage medium is capable of storing data, and the data stored in the WORM data storage medium are unerasable and unrewritable. The key generator provides a generated key that can be stored in the erasable storage medium. The encrypted write component writes a set of sensitive data encrypted by using the generated key to the WORM storage medium. In response to a request for deleting the set of sensitive data from the WORM storage medium, the key deleter deletes the generated key from the erasable storage medium.

A method and apparatus is provided for the operation of a secure and deduplicated write once read many virtual disk which exceeds the write performance of traditional cryptographic methods. This is achieved through the utilization of a time-memory tradeoff via the empty space on a virtual disk at format time. Traditionally empty space is zeroed to indicate that data is not present. When implementing the apparatus, the empty space is filled with the output of a symmetric-key algorithm uniquely keyed for that specific disk. From an information theoretic point of view, the format operation stores cryptographically structured data, rather than purely redundant data, enabling the write operation that encodes data to be stored on the disk to operate without additional cryptographic computation. This reduced computation requirement for encoding enables the computation required deduplication to operate as if encoding was not being performed, resulting in a net throughput increase.

The present invention relates to pyridinone based azo dyes and / or of anionic azo metal complex dye salts made thereof with cationic basic yellow dyes, which are characterized by an unsaturated bond inbeta-position to the endocyclic N atom of the pyridinone, and to their use in optical layers for optical data recording, preferably for optical data recording using a laser with a wavelength up to 450 nm. The invention further relates to a write once read many (WORM) type optical data recording medium capable of recording and reproducing information with radiation of blue laser, which employs pyridinone based azo dyes and / or anionic azo metal complex dye salts made thereof with cationic basic yellow dyes, which are characterized by an unsaturated bond in beta-position to the endocyclic N atomof the pyridinone, in the optical layer.