Patents by Inventor Yafen Peggy Chang

Yafen Peggy Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8024172
    Abstract: A method and system for emulating tape library commands is disclosed. Tape library commands implemented in response to commands received from a data protection application are emulated in a disk based storage medium so that existing data protection applications may be used to copy data to and from the disk based storage medium.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: September 20, 2011
    Assignee: NetApp, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Gavin David Cohen, Rico Blaser
  • Patent number: 7979654
    Abstract: A system for synchronizing a secondary volume with a primary volume in a continuous data protection system includes scanning means for scanning a region of the primary volume; comparing means for comparing the scanned region with a corresponding region of the secondary volume; storing means for storing an identification of the scanned region in a compare delta map when the comparing means returns a discrepancy between the scanned region and the corresponding region; copying means for copying data from the primary volume to the secondary volume, using the compare delta map as a guide to locate the data to copy; and revising means for revising the compare delta map by removing any changes made to the primary volume during a scan interval, which is a period of time required to scan the primary volume.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: July 12, 2011
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7904679
    Abstract: A method and apparatus for managing backup data is disclosed. A data backup system defines a plurality of time windows for creating and maintaining backup data in accordance with a data backup policy. Each of the time windows is assigned a predetermined amount of storage space. When the data backup system creates backup data, the system determines whether a storage space assigned to a time window is large enough to accommodate new backup data. If the storage space is large enough, the new backup data is stored. However, if the storage space is not large enough, the system deletes the oldest backup data until enough storage space is obtained.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: March 8, 2011
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7882081
    Abstract: A system for the storage and retrieval of data files includes a data disk, a configuration disk and a controller. Each data file includes one or more data blocks, each data block comprising a data section. The data disk stores the data blocks and is divided into a plurality of block groups. The configuration disk stores a copy of at least a portion of the corresponding meta-data. The controller controls both the data disk and the configuration disk.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: February 1, 2011
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Don Alvin Trimmer, Craig Anthony Johnston, Yafen Peggy Chang, Jerry Kai Lau
  • Patent number: 7797582
    Abstract: A method for tracking changes on a primary volume in a continuous data protection system writes data to the primary volume. A copy of the data is written to a secondary volume, the secondary volume including all writes made to the primary volume. Each write made to the secondary volume is mapped in a data structure, such that the data structure tracks changes on the primary volume between two different points in time.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: September 14, 2010
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Don Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7783606
    Abstract: A method and system for generating a snapshot in a consistent state is disclosed. The system comprises a host computer, a primary data storage, a data protection unit, and a secondary data storage. The data protection unit monitors a state of an email application which is running on the host computer. The data protection unit generates a snapshot of data stored in a primary data storage when the email application is in a consistent state, and stores the snapshot on a secondary storage. In the event of a system failure, the data is recovered using the last snapshot. A method and system for recovering email data from a snapshot in a consistent state using a client is also disclosed.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: August 24, 2010
    Assignee: NetApp, Inc.
    Inventors: Yafen Peggy Chang, Roger Keith Stager, Craig Johnston
  • Patent number: 7720817
    Abstract: A method for browsing objects on a protected volume in a continuous data protection system begins by displaying a list of top-level objects to a user who selects a top-level object to browse. A snapshot is selected from the selected top-level object and is decoded. A list of objects in the selected snapshot is displayed and the user selects an object to browse. The selected object is decoded and operations are performed on the selected object. The user can browse the protected volume by snapshots in the top-level object or by a range of time of coverage of the top-level object.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: May 18, 2010
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7650533
    Abstract: A method for restoring a volume in a continuous data protection system begins by selecting a volume to restore. The selected volume is loaded into a workspace. The selected volume is copied from the workspace to a restore location. Operations are simultaneously performed on the selected volume while the selected volume is being copied. The selected volume is accessed on the restore location once the copying is complete.
    Type: Grant
    Filed: April 20, 2006
    Date of Patent: January 19, 2010
    Assignee: NetApp, Inc.
    Inventors: Pawan Saxena, Yafen Peggy Chang, Roger Keith Stager
  • Patent number: 7567993
    Abstract: The invention is a method and system for copying backup data to a virtual tape library (VTL), where data written to the VTL can optionally be stored on removable disk media for offsite storage. The invention minimizes dependency on tape media without taxing the resources of any of the servers and without the need for the data protection application (DPA) to perform a second backup pass. Backup data written to the VTL can optionally be copied to the VTL's default storage area and/or to a predetermined set of disks that may be removed and stored offsite.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: July 28, 2009
    Assignee: Netapp, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7490103
    Abstract: A method and system for generating a snapshot in a consistent state is disclosed. The system comprises a host computer, a primary data storage, a data protection unit, and a secondary data storage. The data protection unit monitors a state of an application which is running on the host computer. The data protection unit generates a snapshot of data stored in a primary data storage when the application is in a consistent state, and stores the snapshot on a secondary storage. In the event of a system failure, the data is recovered using the last snapshot.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: February 10, 2009
    Assignee: NetApp, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7426617
    Abstract: A method for synchronizing a secondary volume with a primary volume in a continuous data protection system begins by scanning a region of the primary volume, which is then compared with a corresponding region of the secondary volume. An identification of the scanned region is stored in a compare delta map when the comparison results in a discrepancy between the scanned region and the corresponding region. Data is copied from the primary volume to the secondary volume, using the compare delta map as a guide to locate the data to copy. If the data protection system has failed just prior to the restore process being initiated, it is termed a re-baseline, and the entire primary volume is scanned. If the data protection system is active prior to the restore process being initiated, it is termed a re-synchronization, and is optimized by scanning only select regions of the primary volume.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: September 16, 2008
    Assignee: Network Appliance, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7406488
    Abstract: A method and system where data is maintained in a continuous data protection system is disclosed. A primary volume may be protected according to an any-point-in-time (APIT) window wherein restores may be performed at any time as desired. The APIT window may be of any time duration as desired. Outside of the APIT window, a retention policy for phasing out data may be established as desired.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: July 29, 2008
    Assignee: NetApp
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Publication number: 20080147756
    Abstract: A system for synchronizing a secondary volume with a primary volume in a continuous data protection system includes scanning means for scanning a region of the primary volume; comparing means for comparing the scanned region with a corresponding region of the secondary volume; storing means for storing an identification of the scanned region in a compare delta map when the comparing means returns a discrepancy between the scanned region and the corresponding region; copying means for copying data from the primary volume to the secondary volume, using the compare delta map as a guide to locate the data to copy; and revising means for revising the compare delta map by removing any changes made to the primary volume during a scan interval, which is a period of time required to scan the primary volume.
    Type: Application
    Filed: February 29, 2008
    Publication date: June 19, 2008
    Applicant: NETWORK APPLIANCE, INC.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7325159
    Abstract: In a continuous data protection system having a primary volume and a secondary volume, a method for data recovery begins by selecting a snapshot of the primary volume to be recovered and a location on which the snapshot is to be loaded. A point in time (PIT) map is created for the selected snapshot, and the selected snapshot is loaded at the selected location. A data block from the PIT map is resolved to determine which block on the secondary volume is presented as being part of the snapshot. The snapshot is accessed via a host computer as if the snapshot was the primary volume at an earlier point in time, corresponding to the time of the selected snapshot.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: January 29, 2008
    Assignee: Network Appliance, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 7315965
    Abstract: A method and system wherein data is structured so that writes may be continuously duplicated and a protected volume may be restored to a particular point in time as desired. Writes are continuously duplicated on a secondary volume and organized into delta maps. The delta maps indicate which memory blocks were written to during a particular time frame.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: January 1, 2008
    Assignee: Network Appliance, Inc.
    Inventors: Roger Keith Stager, Donald Alvin Trimmer, Pawan Saxena, Randall Johnson, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Patent number: 6862656
    Abstract: A system and method for exporting a virtual tape from a virtual tape library. The system preferably presents a user with a user interface styled for manipulating a physical tape library. The virtual tape library performs the data storage and retrieval functions. The system includes the user interface having a plurality of user selectable fields styled to interface with the physical tape library. A data storage medium has at least one virtual library and/or virtual tape defined thereon. The data storage medium is capable of storing a plurality of data in the at least one virtual library and/or virtual tape. A physical data storage device is detachably able to be put in communication with the at least one virtual library and/or virtual tape to receive at least a portion of the plurality of data therefrom.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: March 1, 2005
    Assignee: Alacritus, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Jerry Kai Lau, Gavin David Cohen, Rico Blaser
  • Patent number: 6851031
    Abstract: A method of importing a plurality of data from a physical data storage device into a virtual tape library system that is used with a data protection application. The virtual tape library system is usable with an existing data protection application designed for use with a physical tape library without modifying the existing data protection application. The method includes: triggering a signal representing a command to import the plurality of data from the physical data storage device; providing a controller that receives the signal; providing a data storage medium in communication with the controller, the data storage medium has at least one virtual library defined thereon; and copying at least a portion of the plurality of data from the physical data storage device to a virtual tape.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: February 1, 2005
    Assignee: Alacritus, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Jerry Kai Lau, Gavin David Cohen, Rico Blaser
  • Publication number: 20040153739
    Abstract: A method and system for copying backup data to a virtual tape library (VTL) where additional copies of data written to the VTL may be created and used for offsite storage is disclosed. Backup data written to the VTL may be copied to the VTL's default storage area as well as a predetermined set of disks that may be removed and stored offsite, as desired.
    Type: Application
    Filed: December 9, 2002
    Publication date: August 5, 2004
    Applicant: Alacritus, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Rico Blaser
  • Publication number: 20040111251
    Abstract: A method and system for emulating tape library commands is disclosed. Tape library commands implemented in response to commands received from a data protection application are emulated in a disk based storage medium so that existing data protection applications may be used to copy data to and from the disk based storage medium.
    Type: Application
    Filed: December 9, 2002
    Publication date: June 10, 2004
    Applicant: Alacritus, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Gavin David Cohen, Rico Blaser
  • Publication number: 20040044842
    Abstract: A system and method for exporting a virtual tape from a virtual tape library. The system preferably presents a user with a user interface styled for manipulating a physical tape library. The virtual tape library performs the data storage and retrieval functions. The system includes the user interface having a plurality of user selectable fields styled to interface with the physical tape library. A data storage medium has at least one virtual library and/or virtual tape defined thereon. The data storage medium is capable of storing a plurality of data in the at least one virtual library and/or virtual tape. A physical data storage device is detachably able to be put in communication with the at least one virtual library and/or virtual tape to receive at least a portion of the plurality of data therefrom.
    Type: Application
    Filed: August 30, 2002
    Publication date: March 4, 2004
    Applicant: Alacritus, Inc.
    Inventors: Don Alvin Trimmer, Roger Keith Stager, Craig Anthony Johnston, Yafen Peggy Chang, Jerry Kai Lau, Gavin David Cohen, Rico Blaser