Tape Patents (Class 714/771)
  • Patent number: 9983926
    Abstract: An apparatus and corresponding method for protecting stored data. The apparatus includes a first encoder, a memory, a second encoder and a comparator. The first encoder is configured to generate first redundancy bits using a protection method to protect input data bits, whereas the input data bits are assigned to at least one of a plurality of classes. The memory is configured to store selectively inverted input data bits and/or selectively inverted first redundancy bits, whereas the selective inversion is based on the assigned at least one of the plurality of classes. The second encoder is configured to generate second redundancy bits using the protection method by encoding the selectively inverted input data bits. The comparator is configured to generate an alarm signal if the second redundancy bits are different from the first redundancy bits.
    Type: Grant
    Filed: October 5, 2015
    Date of Patent: May 29, 2018
    Assignee: Infineon Technologies AG
    Inventor: Holger Busch
  • Patent number: 9594642
    Abstract: Various embodiments for data error recovery in a tape storage system, by a processor device, are provided. In one embodiment, a method comprises, in a tape storage system using a hardware-initiated and microcode-initiated iterative decoder, initializing a microcode cut/paste algorithm on a buffered dataset by copying the buffered dataset to a reserved buffer segment; wherein the buffered dataset is a most corrected buffered dataset developed by at least one iterative decode cycle; and the buffered dataset, updated C1 data row error flags, and a correction status recovered by the at least one iterative decode cycle are cut and pasted over a working copy of a dataset resident in the reserved buffer segment.
    Type: Grant
    Filed: January 5, 2016
    Date of Patent: March 14, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Steven R. Bentley, Pamela R. Nylander-Hill, Keisuke Tanaka
  • Patent number: 9311960
    Abstract: In one embodiment, a system includes a controller and logic integrated with and/or executable by the controller, the logic being configured to write a data set to a first write section of a magnetic medium, the data set including a plurality of sub data sets, each including a data array organized in rows and columns, each row of the data array including a CWI-4. A first portion of the data set is stored as CWI-4 sets to the first write section of the magnetic medium with first headers. The logic is also configured to rewrite at least some of the data set as rewritten CWI-4 sets to a rewrite section of the magnetic medium as rewritten CWI-4s having corresponding rewrite headers. A length of any one of the rewrite headers is greater than a length of any one of the first headers.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: April 12, 2016
    Assignee: International Business Machines Corporation
    Inventors: Steven R. Bentley, Roy D. Cideciyan, Simeon Furrer, Kenji Ohtani
  • Patent number: 9230600
    Abstract: Provided is a method for recording data to a tape medium in such a manner as to achieve the easy management of mutually related multiple data pieces. First data and second data continuously received as a file from a higher level apparatus are accumulated in multiple buffer segments in the form of multiple successive data sets. A data structure is determined for each of the accumulated data sets. Management information indicating a result of the determination is added to the data sets, and the data sets and the management information thereof are stored into the tape medium.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: January 5, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Hiroshi Itagaki, Toshiyuki Shiratori
  • Patent number: 9032271
    Abstract: In some embodiments of the present invention, a data storage system includes a controller and a non-volatile memory array having a plurality of memory pages. The controller performs a method that efficiently resolves the lower page corruption problem. In one embodiment, the method selects programmed lower page(s) for which paired upper page(s) have not been programmed, reads data from those selected lower page(s), corrects the read data, and reprograms the read data into those lower page(s). Since the number of lower pages in this condition is typically low (e.g., several pages in a block with hundreds or thousands of pages), this is a much more efficient method than reprogramming the entire block. In another embodiment, a similar reprogramming method is applied as a data recovery scheme in situations in which only lower pages are programmed (e.g., SLC memory, MLC memory in SLC mode, etc.).
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: May 12, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yongke Sun, Dengtao Zhao, Jui-Yao Yang
  • Publication number: 20150058696
    Abstract: In one embodiment, a system for providing header protection in magnetic tape recording is adapted to write a codeword interleave (CWI) set on a magnetic tape including a plurality of CWIs equal to a number of tracks, wherein a data set includes a plurality of CWI sets, provide a CWI set header for the CWI set, the CWI set header including a CWI header for each CWI in the CWI set, each CWI header including at least a CWI Designation (CWID) which indicates a location of the CWI within the data set, calculate or obtain CWID parity for all CWIDs in the CWI set header, the CWID parity including error correction coding (ECC) parity, and store the CWID parity to one or more fields which are repeated for each CWI header in the CWI set header without using reserved bits in the CWI set header to store the CWID parity.
    Type: Application
    Filed: August 26, 2013
    Publication date: February 26, 2015
    Applicant: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Robert A. Hutchins, Thomas Mittelholzer, Keisuke Tanaka
  • Patent number: 8874996
    Abstract: A memory device comprises a normal storage area comprising first and second subsets configured to store first and second normal data, respectively, an error code storage area configured to store first and second error codes corresponding to the first and second normal data, an error detector configured to receive the first and second normal data and the first and second error codes, and further configured to detect the presence or absence of one or more errors in the first and second normal data or the first and second error codes, and a refresh controller configured to set respective refresh cycle times of the first and second subsets to different values according to the presence or absence of one or more errors in the first and second normal data or error codes.
    Type: Grant
    Filed: August 29, 2012
    Date of Patent: October 28, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Bu-Il Jung
  • Patent number: 8869011
    Abstract: In one embodiment, a method includes receiving a headerized SDS protected by unequal error protection; decoding a header from the headerized SDS and removing an impact of the header from C1 row parity to obtain a SDS; for a number of iterations: performing C2 column decoding, for no more than a number of interleaves in each row of the SDS: overwriting a number of columns with successfully decoded C2 codewords, erasing a number of C2 codewords, and maintaining remaining columns as uncorrected, performing C1 row decoding; for no more than a number of interleaves in each row of the SDS: overwriting a number of rows with successfully decoded C1 codewords, erasing a number of C1 codewords, and maintaining remaining rows as uncorrected; and outputting the SDS when all rows include only C1 codewords and all columns include only C2 codewords; otherwise, outputting indication that the SDS cannot be decoded properly.
    Type: Grant
    Filed: January 3, 2013
    Date of Patent: October 21, 2014
    Assignee: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Robert A. Hutchins, Thomas Mittelholzer, Keisuke Tanaka
  • Patent number: 8656252
    Abstract: A non-volatile storage device includes one or more non-volatile memories for storing data, and a memory controller for carrying out the control of the non-volatile memory. The non-volatile memory includes the plurality of blocks, which are erase units, and the block includes the plurality of pages, which are write units of data, in each of the blocks at least one set of pages existing which include at least two pages sharing one word line. The memory controller configures a plurality of error correcting groups, each including at least one data page, which is a page for storing data, and at least one error correcting code page for storing a code for error correcting calculation of the data page, and assigns a page of a separate word line with respect to each of the data page and the error correcting page in the same error correcting group.
    Type: Grant
    Filed: May 3, 2012
    Date of Patent: February 18, 2014
    Assignee: Panasonic Corporation
    Inventors: Hirokazu So, Toshiyuki Honda
  • Patent number: 8645800
    Abstract: A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: February 4, 2014
    Assignee: International Business Machines Corporation
    Inventors: Roy Daron Cideciyan, Hisato Matsuo, Thomas Mittelholzer, Kenji Ohtani, Paul J Seger, Keisuke Tanaka
  • Publication number: 20130326311
    Abstract: In one embodiment, a method for writing data to a magnetic tape utilizing a rate-(232/234) reverse concatenated modulation code includes receiving a data stream comprising one or more data sets, separating each data set into a plurality of sub data sets, encoding each sub data set with a C2 encoding, encoding each C2-encoded sub data set with the modulation code, encoding each modulated sub data set with a C1 encoding, and simultaneously writing the encoded modulated sub data sets to data tracks of the magnetic tape. Other methods for writing data to a magnetic tape utilizing a rate-(232/234) reverse concatenated modulation code are described according to various other embodiments.
    Type: Application
    Filed: February 4, 2013
    Publication date: December 5, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roy D. Cideciyan, Robert A. Hutchins, Thomas Mittleholzer, Sedat Oelcer
  • Patent number: 8583990
    Abstract: An apparatus and associated method provided for a plurality of storage elements arranged and concurrently accessible in an array. A controller executes programming instructions stored in memory to append an error correction code (ECC) block to a first data block and to store the first data block with appended ECC block in a first storage element of the plurality, the appended ECC block associated with a second data block other than the first data block.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: November 12, 2013
    Assignee: Spectra Logic Corporation
    Inventor: Matthew Thomas Starr
  • Publication number: 20130283127
    Abstract: In one embodiment, a method includes executing a first forward loop of a detection algorithm on a block of signal samples during a first time interval, executing a first reverse loop of the detection algorithm on the block during a second time interval to produce first soft information, executing a decoding algorithm on the block during a third time interval using the first soft information to produce second soft information, executing a second forward loop of the detection algorithm on the block during a fourth time interval using the second soft information, executing a second reverse loop of the detection algorithm on the block during a fifth time interval to produce third soft information, executing the decoding algorithm on the block during a sixth time interval using the third soft information to produce a decoded block of signal samples, and outputting the decoded block of signal samples.
    Type: Application
    Filed: February 7, 2013
    Publication date: October 24, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roy D. Cideciyan, Robert A. Hutchins, Thomas Mittelholzer, Sedat Oelcer
  • Patent number: 8495470
    Abstract: A method for efficiently rewriting data to tape is disclosed herein. In one embodiment, such a method includes writing a data set to tape, the data set comprising S sub data sets of fixed size, each sub data set comprising N code word interleaves (CWIs). The method further includes reading the data set while writing it to the tape to identify faulty CWIs. While reading the data set, the method buffers the faulty CWIs (such as by storing, identifying, and/or marking the faulty CWIs) for later retrieval. When the end of the data set is reached, the method writes corrected versions of the faulty CWIs to the end of the data set. A corresponding apparatus is also disclosed and claimed herein.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: July 23, 2013
    Assignee: International Business Machines Corporation
    Inventors: Roy Daron Cideciyan, Thomas Mittelholzer, Kenji Ohtani, Paul J Seger, Keisuke Tanaka
  • Patent number: 8479079
    Abstract: A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: July 2, 2013
    Assignee: International Business Machines Corporation
    Inventors: Roy Daron Cideciyan, Hisato Matsuo, Thomas Mittelholzer, Kenji Ohtani, Paul J Seger, Keisuke Tanaka
  • Publication number: 20130139034
    Abstract: An apparatus and associated method provided for a plurality of storage elements arranged and concurrently accessible in an array. A controller executes programming instructions stored in memory to append an error correction code (ECC) block to a first data block and to store the first data block with appended ECC block in a first storage element of the plurality, the appended ECC block associated with a second data block other than the first data block.
    Type: Application
    Filed: November 30, 2011
    Publication date: May 30, 2013
    Applicant: Spectra Logic Corporation
    Inventor: Matthew Thomas Starr
  • Patent number: 8448256
    Abstract: According to an embodiment, a programmable logic device includes a plurality of logic blocks, memory and a logic unit. The logic blocks are grouped into one or more partitions. The memory stores authentication and partition information uploaded to the programmable logic device prior to partition programming. The logic unit authenticates programming access to the one or more partitions based on the authentication information and controls programming of the one or more partitions based on the partition information.
    Type: Grant
    Filed: February 2, 2009
    Date of Patent: May 21, 2013
    Assignee: Infineon Technologies AG
    Inventors: Joerg Borchert, Jurijus Cizas, Shrinath Eswarahally, Mark Stafford, Rajagopalan Krishnamurthy
  • Patent number: 8413014
    Abstract: A method of writing data to and reading data from a storage medium includes cycle slip detection and correction. An LDPC matrix includes a first area for cycle slip detection and correction. The first area satisfies a set of conditions such that a cycle slip at a particular position creates a pattern of parity check errors indicative of the position and polarity of the cycle slip. Writing user data to the storage medium includes encoding the user data with parity data according to the LDPC matrix. Reading the user data and the parity data from the storage medium includes decoding the user data and the parity data according to the LDPC matrix. Decoding includes, upon detecting a pattern of parity check errors indicative of the position and polarity of a detected cycle slip, correcting the detected cycle slip.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: April 2, 2013
    Assignee: Oracle America, Inc.
    Inventors: Jin Lu, Keith G. Boyer
  • Patent number: 8397136
    Abstract: An information recording apparatus and method. The method includes sequentially writing datasets to a recording medium so that each of the datasets can be identified from a certain number indicating an order that the dataset was written, and from the number of writing operations (WP) carried out for the dataset of the certain number to identify a newest dataset among datasets having the same certain number; appending a new dataset onto the old dataset; and controlling execution, in the case where an error occurs at the time of the appending, of the appending step on the old dataset, in a position shifted forward on the recording medium such that the new dataset overwrites a part of the old dataset.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: March 12, 2013
    Assignee: International Business Machines Corporation
    Inventors: Setsuko Masuda, Kenji Nakamura, Yutaka Oishi
  • Patent number: 8316281
    Abstract: An LDPC coding system includes a number of LDPC encoders and a number of LDPC decoders. The number of encoders/decoders is between one and one fewer than the total number of tracks on the high density tape are provided. The LDPC encoders are operable to break data from an incoming data sector into the data blocks to be written to the high density tape. The LDPC decoders are operable to assemble the data blocks into data sectors.
    Type: Grant
    Filed: November 3, 2009
    Date of Patent: November 20, 2012
    Assignee: Oracle America, Inc.
    Inventors: Richard A. Gill, Jin Lu
  • Patent number: 8276045
    Abstract: Conventional C2 coding and interleaving for multi-track data tape in LTO-3/4 do not support recording data onto a number of concurrent tracks which is not a power of two. Higher-rate longer C2 codes, which do not degrade error rate performance, are provided. An adjustable format and interleaving scheme accommodates future tape drives in which the number of concurrent tracks is not necessarily a power of two. A data set is segmented into a plurality of unencoded subdata sets and parity bytes are generated for each row and column. The parameters of the C2 code include N2 as the least common multiple of the number of possible tracks to which codeword objects are to be written. COs are formed from N2 C1 codewords, mapped onto a logical data track according to information within headers of the CO and modulation encoded into synchronized COs which are written to the tape.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: September 25, 2012
    Assignee: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Evangelos S. Eleftheriou, Hisato Matsuo, Thomas Mittelholzer, Paul J. Seger, Keisuke Tanaka
  • Patent number: 8276044
    Abstract: An information recording apparatus includes a writing system for writing the datasets to the recording medium, so that each of the datasets can be identified from a certain number indicating an order that each of the datasets was sequentially written to the recording medium, and from the number of writing operations (WP) carried out for a dataset of the certain number, the writing system writing a first dataset; the writing system being configured for substantially appending a second dataset onto the first dataset, the second dataset having the same certain number as the first dataset, and for setting a value obtained by incrementing the WP of the first dataset as the WP of the second dataset.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: September 25, 2012
    Assignee: International Business Machines Corporation
    Inventors: Setsuko Masuda, Kenji Nakamura, Yutaka Oishi
  • Patent number: 8271857
    Abstract: The invention includes a method for longitudinal position (LPOS) detection in a magnetic tape storage system for storing data upon linear tape open (LTO) magnetic storage tape, which data includes odd and even 36-bit LPOS words with error correcting ability.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: September 18, 2012
    Assignee: International Business Machines Corporation
    Inventors: William J. Kabelac, Barry M. Trager, Shmuel Winograd
  • Publication number: 20120210194
    Abstract: A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein.
    Type: Application
    Filed: April 19, 2012
    Publication date: August 16, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roy D. Cideciyan, Hisato Matsuo, Thomas Mittelholzer, Kenji Ohtani, Paul J. Seger, Keisuke Tanaka
  • Publication number: 20120144271
    Abstract: A method for decoding encoded data comprising integrated data and header protection is disclosed herein. In one embodiment, such a method includes receiving an extended data array. The extended data array includes a data array organized into rows and columns, headers appended to the rows of the data array, column ECC parity protecting the columns of the data array, and row ECC parity protecting the rows and headers combined. The method then decodes the extended data array. Among other operations, this decoding step includes checking the header associated with each row to determine whether the header is legal. If the header is legal, the method determines the contribution of the header to the corresponding row ECC parity. The method then reverses the contribution of the header to the corresponding row ECC parity. A corresponding apparatus (i.e., a tape drive configured to implement the above-described method) is also disclosed herein.
    Type: Application
    Filed: December 1, 2010
    Publication date: June 7, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roy D. Cideciyan, Hisato Matsuo, Thomas Mittelholzer, Kenji Ohtani, Paul J. Seger, Keisuke Tanaka
  • Patent number: 8196019
    Abstract: Error correction coding is provided for codeword headers in a data tape format, such as a Linear Tape-Open, Generation 4 (LTO-4) data tape format. The data tape format defines a codeword quad as having first and second codeword headers interleaved with first and second codeword pairs, each codeword header comprising N bytes ck=c0, c1, . . . , cN?2, cN?1 wherein K bytes c0-cK?1 of the first and second headers in a codeword quad differ such that if one is known the other can be inferred. Each header byte ck of a codeword quad is redefined as comprising two interleaved (m/2)-bit nibbles, ek, ok. For each header, nibbles eK-eN?1 and nibbles oK-oN?1 are generated as a function of nibbles, e0-eK?1 and o0-oK?1, respectively. A codeword is assembled with the redefined headers the codeword quad is then recorded onto a recording medium.
    Type: Grant
    Filed: January 30, 2007
    Date of Patent: June 5, 2012
    Assignee: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Thomas Mittelholzer, Paul J. Seger
  • Patent number: 8185803
    Abstract: A method and apparatus for providing error correction capability to longitudinal position data are disclosed. Initially, data are encoded via a set of even LPOS words and a set of odd LPOS words. The encoded data are then decoded by generating a set of syndrome bits for each of the LPOS words. A determination is then made as to whether or not there is an error within one of the LPOS words based on its corresponding syndrome bits.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: May 22, 2012
    Assignee: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Evangelos S. Eleftheriou, Glen A. Jaquette, Paul J. Seger
  • Publication number: 20110252290
    Abstract: A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein.
    Type: Application
    Filed: April 9, 2010
    Publication date: October 13, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roy D. Cideciyan, Hisato Matsuo, Thomas Mittelholzer, Kenji Ohtani, Paul J. Seger, Keisuke Tanaka
  • Patent number: 8037346
    Abstract: A system for processing a data read error from a tape medium in one embodiment includes a reading section for reading data in data units from a tape medium; a reading control section for controlling said reading section to read data, and on condition that if an error occurs in reading one of said data units, the data unit where the error occurs is considered an error data unit and the reading control section issues an instruction to skip the error data unit and read the next readable data unit immediately after the error data unit; a computation section for computing a number of records and a number of boundary marks included in the error data unit where said error occurs from information about the records and boundary marks included in the data unit preceding the error data unit that is read immediately before said error occurs, and information about the records and boundary marks included in the data unit next to said error data unit, the boundary marks indicating the boundary of a record block; and a commu
    Type: Grant
    Filed: August 11, 2008
    Date of Patent: October 11, 2011
    Assignee: International Business Machines Corporation
    Inventors: Takashi Katagiri, Eiji Tosaka, Katsumi Yoshimura
  • Publication number: 20110107187
    Abstract: An LDPC coding system includes a number of LDPC encoders and a number of LDPC decoders. The number of encoders/decoders is between one and one fewer than the total number of tracks on the high density tape are provided. The LDPC encoders are operable to break data from an incoming data sector into the data blocks to be written to the high density tape. The LDPC decoders are operable to assemble the data blocks into data sectors.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 5, 2011
    Applicant: SUN MICROSYSTEMS, INC.
    Inventors: Richard A. Gill, Jin Lu
  • Publication number: 20110029843
    Abstract: A method of writing data to and reading data from a storage medium includes cycle slip detection and correction. An LDPC matrix includes a first area for cycle slip detection and correction. The first area satisfies a set of conditions such that a cycle slip at a particular position creates a pattern of parity check errors indicative of the position and polarity of the cycle slip. Writing user data to the storage medium includes encoding the user data with parity data according to the LDPC matrix. Reading the user data and the parity data from the storage medium includes decoding the user data and the parity data according to the LDPC matrix. Decoding includes, upon detecting a pattern of parity check errors indicative of the position and polarity of a detected cycle slip, correcting the detected cycle slip.
    Type: Application
    Filed: July 29, 2009
    Publication date: February 3, 2011
    Applicant: SUN MICROSYSTEMS, INC.
    Inventors: Jin Lu, Keith G. Boyer
  • Patent number: 7793041
    Abstract: A method, system, and machine-readable medium for controlling access to data of a tape data storage medium are disclosed. In accordance with one embodiment, a method is provided which comprises conveying data access control metadata from a tape cartridge comprising a tape data storage medium to a host, receiving decrypted metadata from the host, comparing a checksum value determined utilizing the decrypted metadata with checksum data stored within the tape cartridge; and processing a request to access the tape data storage medium received from the host based upon a comparison of the checksum value and checksum data. In the described method embodiment, the data access control metadata comprises encrypted metadata corresponding to a data storage parameter, where data is stored within the tape data storage medium utilizing the data storage parameter and the decrypted metadata is generated by the host utilizing the encrypted metadata.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: September 7, 2010
    Assignee: International Business Machines Corporation
    Inventors: Glen A. Jaquette, James M. Karp
  • Publication number: 20100180180
    Abstract: Conventional C2 coding and interleaving for multi-track data tape in LTO-¾ do not support recording data onto a number of concurrent tracks which is not a power of two. Higher-rate longer C2 codes, which do not degrade error rate performance, are provided. An adjustable format and interleaving scheme accommodates future tape drives in which the number of concurrent tracks is not necessarily a power of two. A data set is segmented into a plurality of unencoded subdata sets and parity bytes are generated for each row and column. The parameters of the C2 code include N2 as the least common multiple of the number of possible tracks to which codeword objects are to be written. COs are formed from N2 C1 codewords, mapped onto a logical data track according to information within headers of the CO and modulation encoded into synchronized COs which are written to the tape.
    Type: Application
    Filed: January 9, 2009
    Publication date: July 15, 2010
    Applicant: IBM CORPORATION
    Inventors: Roy D. Cideciyan, Evangelos S. Eleftheriou, Hisato Matsuo, Thomas Mittelholzer, Paul J. Seger, Keisuke Tanaka
  • Patent number: 7734986
    Abstract: A method for dynamically adjusting read margin and write margin in a tape drive system to recover data is disclosed. The method includes the operations of monitoring a write driver to determine if a change in rewrite activity to a medium has changed and adjusting a percentage of error correcting code (ECC) capability to be used for write errors if the rewrite activity has changed. An apparatus including a tape medium and a read/write controller for performing the method is also disclosed. In one embodiment, the percentage of ECC is decreased if the rewrite activity to the medium increases.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: June 8, 2010
    Assignee: Oracle International Corporation
    Inventor: Richard A. Gill
  • Patent number: 7646835
    Abstract: A method for automatically calibrating intra-cycle timing relationships between command signals, data signals, and sampling signals for an integrated circuit device. The method includes generating command signals for accessing an integrated circuit component, accessing data signals for conveying data for the integrated circuit component, and accessing sampling signals for controlling the sampling of the data signals. A phase relationship between the command signals, the data signals, and the sampling signals is automatically adjusted to calibrate operation of the integrated circuit device.
    Type: Grant
    Filed: November 17, 2003
    Date of Patent: January 12, 2010
    Inventor: Guillermo J. Rozas
  • Publication number: 20090287982
    Abstract: The invention includes a method for longitudinal position (LPOS) detection in a magnetic tape storage system for storing data upon linear tape open (LTO) magnetic storage tape, which data includes odd and even 36-bit LPOS words with error correcting ability.
    Type: Application
    Filed: May 13, 2008
    Publication date: November 19, 2009
    Applicant: International Business Machines Corporation
    Inventors: William J. Kabelac, Barry M. Trager, Shmuel Winograd
  • Patent number: 7577786
    Abstract: A method for accelerating a tape backup system restore process receives a list of files that are to be restored and searches a tape catalogue to find tape volume and file sequence numbers for each file in the list of files, where the catalogue is an alphabetical listing of the contents of one or more backup tape volumes. The process appends the tape volume and file sequence numbers for each of the files to the list of files and then sorts the list of files according to tape volume and file sequence number. Accordingly, a list is obtained including the files that are to be restored, ordered according to the location of the files on the backup tape volumes. The restore process is accelerated by restoring files sequentially from this list and skipping over any intermediate files that are not on the list.
    Type: Grant
    Filed: December 8, 2005
    Date of Patent: August 18, 2009
    Assignee: Quality Systems Associates, Inc.
    Inventor: Clarence B. Matlock, Jr.
  • Patent number: 7433141
    Abstract: A data recording/recovery device (20) comprises a packet generator (34) for including recordable information into a packet (44), the packet initially having a nominal run length limited (RLL) sequence if it were RLL encoded. A randomizer (38) uses a randomizer input value (50) to obtain a modified packet (46) which, when encoded, will at least partially have a different run length limited sequence than the nominal run length limited sequence. A write channel (40) records the modified packet (46) as a track packet at a destination physical location (42) on a storage medium (22). The randomizer input value (50) used to obtain the modified packet (46) is related to a predetermined physical location on the storage medium. In one example embodiment the randomizer input value is related to the destination physical location on the storage medium.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: October 7, 2008
    Assignee: Tandberg Data Corporation
    Inventors: Richard H. McAuliffe, Paul Newsome
  • Patent number: 7421640
    Abstract: A method and apparatus for providing error correction capability to longitudinal position data are disclosed. Initially, data are encoded via a set of even LPOS words and a set of odd LPOS words. The encoded data are then decoded by generating a set of syndrome bits for each of the LPOS words. A determination is then made as to whether or not there is an error within one of the LPOS words based on its corresponding syndrome bits.
    Type: Grant
    Filed: August 17, 2005
    Date of Patent: September 2, 2008
    Assignee: International Business Machines Corporation
    Inventors: Roy D. Cideciyan, Evangelos S. Eleftheriou, Glen A. Jaquette, Paul J. Seger
  • Patent number: 7415653
    Abstract: A method for storing a data block, involving storing the data block in a storage pool, obtaining a data block location, determining a checksum function for the data block, calculating a data block checksum using the checksum function for the data block, and storing a first indirect block in the storage pool, wherein the first indirect block comprises the data block location, the data block checksum, and a checksum function ID corresponding to the checksum function for the data block.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: August 19, 2008
    Assignee: Sun Microsystems, Inc.
    Inventors: Jeffrey S. Bonwick, Matthew A. Ahrens
  • Patent number: 7398351
    Abstract: A method, system, and machine-readable medium for controlling access to data of a tape data storage medium are disclosed. In accordance with one embodiment, a method is provided which comprises conveying data access control metadata from a tape cartridge comprising a tape data storage medium to a host, receiving decrypted metadata from the host, comparing a checksum value determined utilizing the decrypted metadata with checksum data stored within the tape cartridge; and processing a request to access the tape data storage medium received from the host based upon a comparison of the checksum value and checksum data. In the described method embodiment, the data access control metadata comprises encrypted metadata corresponding to a data storage parameter, where data is stored within the tape data storage medium utilizing the data storage parameter and the decrypted metadata is generated by the host utilizing the encrypted metadata.
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: July 8, 2008
    Assignee: International Business Machines Corporation
    Inventors: Glen A. Jaquette, James M. Karp
  • Patent number: 7376888
    Abstract: An error correction code system, e.g. of a magnetic tape drive, applies error correction redundancy to data, separates it, or interleaves it, and records it into separate groups. An error correction encoder applies an outer error correction code to one of the separate groups of information, forming one set of rows of information and outer ECC information. An error correction encoder applies an outer error correction code to another separate group of information, forming another set of rows of information and outer ECC information. A data organizer interleaves the one set of rows of information and outer ECC information with the another set of rows of information and outer ECC information for recording on tracks of a recording media in an interleaved pattern of one set of rows of information and outer ECC information with another set of rows of information and outer ECC information.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: May 20, 2008
    Assignee: International Business Machines Corporation
    Inventors: Glen Alan Jaquette, Johnny Lynn Teale
  • Publication number: 20070300133
    Abstract: A method is disclosed. The method includes performing a first read operation at a tape drive, determining if a minimum number of data bytes have been recovered in the first read operation to perform error correcting codes (ECC), performing a second read operation if the minimum number of data bytes to perform ECC have not been recovered, determining if a minimum number of data bytes have been recovered in the second read operation to perform ECC, combining the recovered data bytes from the first read operation and the second read operation to form combined recovered data bytes, determining if a minimum number of data bytes are included in the combined recovered data bytes to perform ECC and performing ECC if the minimum number of data bytes are included in the combined recovered data bytes.
    Type: Application
    Filed: May 24, 2006
    Publication date: December 27, 2007
    Inventors: Richard Allen Gill, Howard H. Rather
  • Patent number: 7269687
    Abstract: Systems and methods for storing data on a tape medium and coping with defective regions on the tape medium are provided. The method includes: writing a plurality of envelopes of data onto the tape medium, each envelope of data comprising a plurality of blocks of data; detecting a defective region of the tape medium; writing a boundary start field after the defective region, the boundary start field indicating that the defective region has been passed; and writing a boundary end field before the defective region of the tape medium, the boundary end field indicating that the defective region follows the boundary end field.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: September 11, 2007
    Assignee: Quantum Corporation
    Inventors: Dwayne A. Edling, Charles Klomp
  • Patent number: 7266751
    Abstract: In a data recording method and a data recording apparatus relating to the present invention, ECC blocks using 36 product codes are recorded on 12 tracks through scanning operations performed three times. First of all, first sync-blocks each constituted by adding a C1 parity to the data string of video data constituting an internal encoding calculation data stream are sequentially recorded. When the first sync-blocks are completely recorded, second sync-blocks each constituted by adding the C1 parity to the data string of C2 parity constituting the internal encoding calculation data stream are sequentially recorded. By recording the C2 parity at one time in a later stage, the system delay can be minimized.
    Type: Grant
    Filed: April 2, 2004
    Date of Patent: September 4, 2007
    Assignee: Sony Corporation
    Inventors: Kaoru Urata, Shoji Kosuge
  • Patent number: 7213190
    Abstract: A data processing apparatus according an aspect of this invention has a syndrome calculation unit configured to calculate the syndrome of a demodulated data sequence. The syndrome calculation unit includes a calculation unit configured to make the calculation required to realize syndrome calculation of demodulated data for each frame obtained by removing the sync code from one sync frame.
    Type: Grant
    Filed: December 23, 2003
    Date of Patent: May 1, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yukiyasu Tatsuzawa
  • Patent number: 7159166
    Abstract: An error correction method is provided as follows: handling a 2-event error generated very frequently as an object of correction; sequentially finding CRC data for a generated event of an error handled as the defined object of correction at any arbitrary bit position of reproduced data by implementation of a cyclic-replacement process; carrying out an exclusive-addition process of the CRC data to CRC data of the reproduced data in order to virtually carry out a tentative-correction process on a 1-event error at a first bit position; further finding CRC data generated after the tentative-correction process in order to detect a 1-event error at a second bit position; and correcting the 1-event error completing the tentative-correction process at the first position and the 1-event error at the second bit position.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: January 2, 2007
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventor: Hiroyuki Tsuchinaga
  • Patent number: 7072131
    Abstract: A storage device in which file data is divided into multiple blocks for storage on a recording medium. The storage device includes an additional data storing section for storing additional data to be recorded on the recording medium in association with the data to be written, a position determining section for determining recording positions on the recording medium where the blocks should be respectively written, based on the additional data, and a block writing section for writing the respective blocks on the recording positions on the recording medium determined by the recording position determining section. The additional data thus defines a gap length between blocks of recorded data. During a read operation, if the gap length does not comport with the additional data, then an error is assumed.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: July 4, 2006
    Assignee: International Business Machines Corporation
    Inventors: Tomoaki Kimura, Satoshi Tohji
  • Patent number: 6978414
    Abstract: A linear tape data storage device comprises a read head and a write head; a tape transport mechanism for transporting the linear tape data storage medium across the read head and the write head, the device being operated according to a predefined tape format; a DRAM buffer memory for storing data received during a write or a read operation; and error protection means configured to protect said data from soft errors generated by said buffer memory wherein the protection means comprises means for checking parity generated within the tape format itself. In the preferred embodiment the tape format used is the Linear Tape Open (LTO) format.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: December 20, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Catharine Anne Maple, Jonathan Peter Buckingham, Neil Thomas Hutchon
  • Patent number: 6877128
    Abstract: A method, computer program product, and data processing system for recovering corrupted data in a multi-track storage medium, such as magnetic tape, using a Reed-Solomon or other similar error correcting code system, is disclosed. A correction history keeping a tally of actual corrected instances of corruption in the storage medium is established. The “N” tracks requiring the greatest number of actual error corrections are designated as erasures. Any errors in the remaining tracks must be found on an individual basis before being corrected.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: April 5, 2005
    Assignee: Storage Technology Corporation
    Inventors: Keith Gary Boyer, Richard Allen Gill