Apparatus and method for data security in an optical disk storage system

• US 5,706,266 A
• Filed: 05/01/1995
• Issued: 01/06/1998
• Est. Priority Date: 12/20/1991
• Status: Expired due to Fees

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Brownstein, Scott Alan, Lentz, Joseph Paul, Kline, Patrick Joseph, Cushman, Thomas Richard
• Primary Examiner(s): HUBER, PAUL W
• Application Number:
  US08/432,445
• Time in Patent Office: 981 Days
• Field of Search: 369/47, 369/48, 369/54, 369/58, 369/32, 369/275.3, 369/111, 235/454, 235/488, 235/494, 235/462, 235/464, 235/487
• US Class Current: 369/53.21
• CPC Class Codes: G11B 19/04 Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00268 said barcode being recorded in a burst cutting area [BCA]
• CPC Class Codes: G11B 20/00876 wherein physical copy protection means are attached to the medium, e.g. holograms, sensors, or additional semiconductor circuitry
• CPC Class Codes: G11B 20/00927 wherein said defects or errors are generated on purpose, e.g. intended scratches
• CPC Class Codes: G11B 23/284 on the record carrier
• CPC Class Codes: G11B 23/38 Visual features other than those contained in record tracks or represented by sprocket holes the visual signals being auxiliary signals
• CPC Class Codes: G11B 7/00736 Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information sector headers or adresses in prepits G11B7/00745; address data in track wobble G11B7/24082
• CPC Class Codes: G11B 7/24 Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the arrangement of information on the carrier G11B7/007
• CPC Class Codes: G11B 7/26 Apparatus or processes specially adapted for the manufacture of record carriers

Abstract

An optical storage disk for use in an optical storage system includes a storage layer which is capable of being disrupted when a laser beam of sufficient intensity is focused thereon. The optical storage disk has a transparent substrate layer on one side of the storage layer and a lacquer layer on the other side of the storage layer. The disruptions provided by the laser beam are selected to provide human readable and/or machine readable patterns. To reduce the damage to portions of the optical disk other than the storage layer, the storage layer is exposed to the laser beam prior to curing, or prior to applying and curing the lacquer layer. The optical disk can be of the type with data written thereon during fabrication, or the disk can be of the type in which data can be impressed thereon after fabrication of the optical disk. The patterns on the optical disk can be in the form of optical bar codes. In one application of the present invention involving the type of disk on which data can be written after fabrication, the pattern resulting from application of the laser beam to the disk is read by an optical reading device and transferred to the disk in the data format. The resulting embedded characters are used, in conjunction with files stored on the medium, to provide security against unpermitted access to the files. In addition for writable optical storage medium, the embedded characters can be used to prevent inappropriate material from being stored on the optical storage medium

Claims

1. A method of protecting files stored on an optical writable disk, said method comprising the steps of:

physically embedding a first identification signal group in a writable optical disk;

storing a second identification signal group in a file written on said writable optical disk;

on initiation of interaction between an interaction system and said writable optical disk, transferring a representation of said first and said second identification signal group to a signal processing unit of said interaction system;

comparing said first and said second identification signal group representation in said signal processing unit and continuing interaction between said interaction system and said writable optical disk only when said comparison between said first and said second identification signal group representations is positive; and

decoding a transferred file prior to processing by said processing unit;

wherein said interaction system has a third identification signal group associated therewith, said method further comprising the steps of transferring a representation of said third identification signal group to the signal processing unit of said interaction system and comparing said third and first identification signal group representations in said signal processing unit and continuing interaction between said interaction system and said writable optical disk only when said comparison between said first and third identification signal group representations is positive.

2. The method of claim 1 further comprising a step of encoding a current file prior to a writing of said current file on said writable optical disk.

3. A method of protecting files stored on an optical disk, said method comprising the steps of:

reading a bar code character group embedded in said optical disk and reading a medium identification signal group stored on said optical disk with a reading unit of an interaction system;

transferring said bar code character group and said medium identification signal group from said reading unit to a signal processing unit of said interaction system;

comparing said bar code character group and said medium identification signal group with said signal processing unit of said interaction system;

continuing interaction between said interaction system and said optical disk when said comparison between said bar code character group and said medium identification signal group is indicative of a non-compromised disk;

reading a file identification signal group from a file stored on said disk with said reading unit of said interaction system;

transferring said file identification signal group to said signal processing unit of said interaction system;

comparing said file identification signal group with said medium identification signal group with said signal processing unit of said interaction system; and

continuing interaction between said interaction system and said optical disk when said comparison between said file identification signal group and said medium identification signal group is indicative of a non-compromised disk.

4. A method of protecting files stored on an optical disk as claimed in claim 3, further comprising the steps of:

comparing a system identification signal group stored in said interaction system with at least one of said bar code character group and said medium identification signal group; and

continuing interaction between said interaction system and said optical disk when said comparison between said system identification signal group and at least one of said bar code character group and said medium identification signal group is indicative of a non-compromised disk.