JP2008507070A - Combination of DRM data and UDF in optical media - Google Patents

Abstract

  The present invention relates to an apparatus for an optical carrier. The device comprises a local storage device and a control unit. The control unit controls the storage in the storage device of the last data set written on the optical carrier. The control unit then triggers the writing of digital rights management data to the disk, and the data set temporarily stored in the local storage device is written back to the disk. If the data set is an ICB associated with the VAT of the disc, the carrier meets the requirements and UDF standards specific to some DRM related standards such as the Sapphire project.

Description

  The invention is in the field of optical storage devices in which the record carrier has a main program storage area. An object of the present invention is to incorporate security measures into an optical disc, and more specifically, to define details of writing of digital copyright management data in the main program storage area.

  A general file structure of a writable optical storage medium is defined in the UDF (Universal Disk Format) standard. A typical file system imposes conditions on file location and possible read / write processes. Among these conditions, UDF imposes the order in which several files must be written. For example, the UDF standard stipulates that the last written sector must be an ICB (Information Control Block) of VAT (Virtual Allocation Table) in order to open a CD-R. While this type of requirement may seem easy to meet, it cannot be avoided. In practice, meeting this requirement is critical to the mounting process, as failure to find an ICB where the ICB is considered to be located will cause read errors and operational failures. is there.

  In addition to the requirements imposed by common file system standards such as those mentioned above, the electronics industry can reliably prevent the loss of content and the usage of available content is closely monitored and restricted. In order to be able to do so, we are trying to incorporate technical security measures. In this way, industry and content providers are strongly promoting the universal incorporation of digital rights management data on optical discs. To that point, solutions are being discussed in industry consortiums and standards are being developed. Most approaches specify stringent conditions that need to be met to ensure product interoperability. One of these approaches is called the Sapphire specification. The Sapphire project describes the keys and rights for the protected content on the disc, and these keys and rights are securely stored in the so-called KLA (KeyLocker Area) in the lead-in part of the disc or in the program area. Remembered. One of the specifications is that the KLA is written immediately before the ICB associated with the VAT. VAT is used only when the type of access to the disk is sequential, and is therefore inherent to CD-R and not mandatory for CD-RW. The entry point of the DRM data is contained in the DRM pointer entry, and more specifically in the ALP (adaptation layer parameter space) where the physical locations of all the key locker copies are listed. The key locker is a structure including both a key and a right for protected data. KLA is an area on the disk reserved for ALP and key lockers. In the case of a write-once (write-once) access type optical disc, the DRM data can be placed anywhere in the program area, and the DRM pointer entry is placed anywhere after the DRM data. I can do it. One method for finding DRM data stored on disk is disclosed in European Patent Application Publication No. 2004 / 021345A1, which is hereby incorporated by reference. This document discloses a method for accessing digital copyright management data stored in a program area of a record carrier which is a write-once disc or a rewritable disc. The proposed solution adds an entry in the disk to allow the drive to find a DRM pointer entry (ALP) that guides DRM data stored on the disk.

  However, writing KLA to a location different from the location specified in the sapphire project can delay disc reading and content playback. In practice, if the KLA cannot be easily located at a predetermined location next to the ICB, the drive operating system must first scan the entire disk before processing the stored content. And such a scan can take minutes or hours.

  As mentioned above, the UDF standard imposes a condition on the position of the ICB on the disc, and current standardization activities are in the direction of imposing a condition on the positioning of the KLA. Therefore, both requirements need to be met at the same time. Such an arrangement works well during reading. This is because the ICB is in the last written sector of the program area and the KLA is located nearby. The problem occurs when KLA writing is performed. In practice, in the host / drive optical system, both the host and the drive are responsible for writing data, but none is fully controlled when using general UDF support. Therefore, it specifies a writing mechanism that will meet both the UDF standard and the sapphire specification or any other specification that will impose the same limitations on DRM data without affecting the general structure of the disc. There is a need to.

  Therefore, it is an object of the present invention to provide a solution that satisfies both any standard that will impose conditions on DRM-related data and the general file system defined in UDF.

  The principle of the present invention is to incorporate usage restrictions on content stored on a conventional recordable optical disc.

  For this purpose, a method for storing data on a record carrier of the type described above is presented. The method includes a first step in which a data set last written to the main program storage area of the disk is stored in a storage device of the drive. Next, digital copyright management data is written in the main program storage area. The DRM data makes it possible to control access to protected content stored on the record carrier. When the DRM data is written to the disk, the data set stored in the storage device of the drive is sequentially written back to the main program storage area after the DRM data.

  The present invention proposes to temporarily store the last written sector in the storage device of the drive while writing data relating to digital rights management to the disk. The data temporarily stored in the storage device is then written back next to the DRM data on the disk. Therefore, when the data temporarily stored in the storage device of the drive is an ICB, the present invention advantageously solves the unsolved problem. In fact, if the carrier is UDF compliant, the last written sector will actually contain the ICB and VAT. Thus, the present invention ensures that the ICB is the final sector written to the disk last, and that the DRM data is written sequentially next to the ICB.

  In an exemplary embodiment of the invention, the method is performed upon request to write DRM data to the carrier. Such a request may be placed below other commands such as an eject command, a shutdown command, or such a request may be generated based on the need to update the DRM data. For example, the system may be configured to automatically update the DRM data if an update is pending for a predetermined period of time on the drive or if the number of updates pending exceeds an acceptable limit. Good. The writing of the DRM data may be triggered by shutting down the drive or by ejecting the carrier from the drive.

  The invention further relates to a drive device having a receptacle into which a record carrier can be inserted. The record carrier may be an optical disc having a UDF definition structure including a lead-in storage area, a main program storage area, and a lead-out storage area. The device also includes control means and a storage device adapted to control the writing of data to the record carrier. The apparatus of the present invention is an apparatus in which the control means controls storage of the data set written last in the main program storage area in the storage device. The control means then controls writing of data relating to digital copyright management to the main program storage area. Such data defines rules regarding access to the content on the record carrier. Further, the control means controls writing of the data set stored in the storage device to the main program storage area.

  These and other aspects of the invention are described and elucidated with reference to the following examples.

  The present invention will now be described in more detail by way of example with reference to the accompanying drawings.

  FIG. 1 shows a block diagram of a playback system 100 according to the present invention. In order to read user data from the disc 102, a read unit 104 is provided. There is an overall consensus among industry players and content providers that develop digital rights management (DRM) systems that define usage restrictions on some or all of the user data. This is because the content stored on the disc 102 may be encrypted, and the disc 102 stores an encryption key that is used to decrypt the content so that the user can process the content. It means that there is a case. Further, a usage right can be stored on the disk 102 that indicates, for example, whether the user is allowed to make a copy of the content. Such usage rights and keys are called DRM data. Furthermore, the reading unit 104 is provided to read out such DRM data. However, first, a pointer that points to the DRM data needs to be found, and the reading unit 104 is provided with an evaluation unit for this purpose. When the evaluation unit in the read unit 104 finds the DRM pointer, the DRM data is supplied to the control block 114 via the lead 206. The control block 114 is a digital signal processing unit (processing for content on the disc 102 and format specific data) when the content is written to the disc 102 or when the content is played from the disc 102. (DSP) 110. The read DRM data is used to control the output of user data, i.e., the control unit 114, for example, by prohibiting the output of the output signal OUT if the right to use prohibits the output, Alternatively, the content playback unit 112 of the DSP 110 is controlled by enabling data decryption before the data is played back to the user. The present invention is in no way limited to the usage rights and key encryption mechanisms described above, thereby including other usage restrictions or any other type of control in content access or processing.

  The playback system 100 of FIG. 1 may accept a writable type disc and additionally includes a writing unit 108 for writing content to the disc 102. The disc 102 is a CD-R based on the Orange Book Part II of the standard, i.e. the disc 102 is writable once, but the general principle of the invention is that the rewritable disc or other It can also be applied to types of optical storage media. For example, the present invention is also suitable for the upcoming Blu-ray discs, particularly BD-R and DVD + R / -R.

  Data IN supplied to the input unit of the DSP unit 110 is transmitted to the writing unit 108 via the lead wire 204. The DSP 110 can control how the write unit 108 writes data IN to the disk 102 via the control lead 202. The DSP 110 may also control the writing of data obtained from the storage device 106 of the system 100 to the disk 102 as described below.

  The playback system also includes a storage device 106 for storing specific format data associated with the disc 102, user data, and content. The storage device 106 may include a temporary storage for storing a data set having a short life cycle, ie, a data set that can be disposed of after a read or write cycle, or if the inserted disk 102 is ejected. The storage device 106 may also include a permanent storage for permanent storage of erasable or non-erasable content and user and standard specific data.

  In this exemplary embodiment, system 100 is compliant with UDF and sapphire. As a result, system 100 and disk 102 meet the aforementioned requirements. Thus, to ensure that there is an ICB block in the last written sector and a KLA next to the ICB, the system 100 operates as follows.

  System 100 may be designed to automatically trigger the writing of KLA data under certain circumstances. KLA writing can be initiated in two ways. In the first case scenario, the application responsible for writing the content on the disc 102 sends a command to write the KLA to the writing unit 108. The application may run on the DSP 110 and the external system 100. The write command may be part of a write procedure, for example, ending the writing of any content on the disc 102. Thus, whenever the DSP 110 controls the writing of a data set secured by the associated DRM rights, the writing is finally accompanied by a command to write a KLA representing the rights of the DRM. The KLA data may be received along with the content to be written to the disc 102 or stored in advance in the storage device 106 and obtained from the storage device 106. The DSP 110 may also issue a write command when a pending update of KLA data temporarily stored in the storage device 106 has been suspended for a very long time. The KLA update on the disk 102 can also be performed at regular intervals.

  In another example, when the disk 102 is ejected from the system 100, KLA data is written. The DSP 110 constantly monitors whether or not the KLA cached in the storage device 106 has been changed. The KLA is changed when content is written or when the unit 104 reads content from the disc 102. For example, the right to watch a movie may limit the maximum number of views to the user. Accordingly, when the content is viewed, the KLA data associated with the movie is cached in the storage device 106 and updated. The above is given as an example, and the present invention is also directed to a system that does not necessarily involve a change in KLA for reading. Finally, when the system 100 is turned off in response to an external command COM, or when the disk 102 is ejected, the system DSP 110 checks whether an update of KLA data is pending in the device 106. Accordingly, the KLA on the disk 102 is changed before shutdown or before the disk 102 is ejected.

  Although a KLA write or update may be initiated in the specific situations described above, the present invention includes that any other situation not described herein can result in a KLA write.

  2a, 2b and 2c show the structure format of the disc 102 as defined by the UDF standard at three points in time. The disk 102 includes a lead-in unit 402, a main program storage area 404, and a lead-out unit 406. The lead-in part and lead-out part are reserved areas on the disk 102 and are not yet written. In FIG. 2 a, the writing unit 108 has written a data set 408 to the main program area of the disk 102. The system 100 is UDF compliant, so when the writing unit 108 writes the data set to the disk 102, it subsequently writes the associated VAT ICB to the main program storage area of the disk 102. In a subsequent operation, a request to write KLA to disk 102 is made in one of the above situations. In that case, the DSP 110 controls the read unit 104 to copy the last written data block from the disk 102 to the storage device 106. At the time represented in FIG. 2a, the last written block is the VAT ICB. The DSP 110 then controls the writing of the KLA to the disk 102, as shown in FIG. 2b, and then in the next step the cached VAT ICB stores the program storage from the storage device 106 to the disk 102. Control writing to the area. Finally, the structure of the disk 102 is shown in FIG. 2c, the last sector written is still the VAT ICB, and the DRM data contained in the KLA is stored next to the VAT ICB in the program area. Is done. Therefore, an advantage of one or more embodiments is that it allows for quick retrieval of DRM pointers and data contained within the KLA while complying with the UDF standard. The present invention allows digital rights management to be added to an optical disc without changing general software and hardware portions of the system 100, and the present invention only results in optical drive changes.

2 is a carrier / drive system of the present invention. 2 shows the layout of the carrier of the present invention. 2 shows the layout of the carrier of the present invention. 2 shows the layout of the carrier of the present invention.

Claims (10)

A method of storing data on a record carrier having a main program storage area,
Storing the data set last written to the main program storage area of the disk in a storage device of a drive;
Writing digital rights management data in the main program storage area for controlling access to content on the record carrier;
Writing the data set stored in the storage device of the drive in the main program storage area next to the digital rights management data.   The method of claim 1, wherein the storing and writing are performed in response to a request to write the digital rights management data issued at the drive.   3. The method of claim 2, wherein the request is triggered by an eject command that ejects the disk from the drive.   The method of claim 2, wherein the request is triggered when the number of updates pending for the digital rights management data exceeds a threshold value.   The method of claim 2, wherein the request is triggered based on a period of time for which an update is pending.   The method of claim 1, wherein storing in the storage device of the drive is simultaneous with writing the data set to the program storage area of the disk.   The method of claim 1, wherein storing the data set in a storage device of the drive comprises copying the data set from the main program storage area.   The method of claim 1, wherein the data set is an ICB associated with a VAT stored on the disk.   The method of claim 1, wherein the digital rights management data is stored in a KLA as defined in the sapphire standard. A container containing a record carrier including a main program storage area;
A storage device;
Control means adapted to control the writing of data to the record carrier,
The control means was last written to the main program storage area followed by writing to the main program storage area data relating to digital rights management for controlling access to content on the record carrier An apparatus for controlling storage of a data set in the storage device, and further controlling writing of the data set stored in the storage device to the main program storage area.

Images