Browse Prior Art Database

Write Once Read Many Capability for Tape Products

IP.com Disclosure Number: IPCOM000114089D
Original Publication Date: 1994-Nov-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 38K

Publishing Venue

IBM

Related People

Allen, VK: AUTHOR

Abstract

This invention presents a method where-by a customer can, via software control, prevent any further writing on a piece of tape media. Once 'applied' this write protection is intentionally irrevocable, i.e., The tape may be read many more times, but all further writing is prevented.

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This is the abbreviated version, containing approximately 76% of the total text.

Write Once Read Many Capability for Tape Products

      This invention presents a method where-by a customer can, via
software control, prevent any further writing on a piece of tape
media.  Once 'applied' this write protection is intentionally
irrevocable, i.e., The tape may be read many more times, but all
further writing is prevented.

      Write-Once-Read-Many (WORM) is the usual term applied to media
that has been written, cannot be re-written and can/may be read many
times.

The invention works as follows:
  o  A data field in the Volume Control Region (VCR) is turned-on by
      the tape drive firmware when a command identified as "SET WORM"
      is received from the software/initiator.  The VCR consists of a
      set of data elements and fields that are read/sampled by the
      drive immediately upon the media being mounted.  The drive
reads
      the VCR in order to understand tape format, etc.
  o  Any further attempts to write/change/update the media for any
      reason are rejected by the drive's firmware/hardware.
  o  Two new software/initiator commands are available:
     -  SET WORM, as previously described allows the
         software/initiator to turn on WORM mode for the currently
         mounted volume.
               If a SET WORM command is received and cannot be
        successfully executed (no tape currently mounted/ready) the
        command is reje...