KR20070028615A - Combining digital rights management data and general-purpose disc formats on optical media - Google Patents

Abstract

The present invention relates to an apparatus for an optical medium. The device has a local memory and a control unit. The control unit controls the storage of the data set last recorded on the optical medium in the storage device. Thereafter, the control unit starts recording of the digital rights management data on the disk, and the data set temporarily stored in the local storage is again recorded on the disk. If the data set is an information control block associated with a disk's virtual allocation table, the optical medium meets UDF specifications and requirements specific to some DRM related standards, such as sapphire projects.

Description

Combining digital rights management data and general-purpose disk formats on optical media {COMBINING DRM DATA AND UDF ON OPTICAL MEDIA}

The present invention relates to the field of optical storage in which the recording medium has a main program memory area. The present invention relates to the integration of a security mechanism on an optical disc, and more particularly to the contents of recording digital rights management data in a main program memory area.

The general file structure of recordable optical storage media is specified in the Universal Disk Format (UDF) standard. This general purpose file system imposes conditions on file location and read / write operation processing. Among these conditions, the UDF specifies the order in which some files should be written. For example, the UDF standard stipulates that for an open CD-R, the last recorded sector should be an Information Control Block (ICB) of the Virtual Allocation Table (VAT). While this kind of requirement seems simple to implement, it is impossible to circumvent it. In fact, reading errors and computation errors can occur if the ICB is not found where it is supposed to be located, so meeting these requirements is critical to the mounting process.

In addition to the requirements imposed by general-purpose file systems such as those described above, the electronics industry is attempting to integrate technical security mechanisms to ensure that content can be closely monitored and limited in the use of available content by preventing the loss of rights. . In this regard, solutions are being discussed in industry consortiums and standards are being researched. Most approaches specify strict 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 permissions for protected content on disk, which are stored securely in the so-called KeyLocker Area (KLA) in the program area or lead-in part of the disk. One of these details is that the KLA is recorded just before the ICB associated with the VAT. VAT is only used when the type of access to the disc is sequential, which is necessary for CD-R but optional for CD-RW. The entry point to the DRM data is contained in the DRM pointer entry, in particular in the adaptation layer parameter space (ALP) where the physical locations of all keylocker copies are listed, where the keylocker is used for protected data. Structure that contains permissions and keys. KLA is an area on disk reserved for keylockers and ALP. For a recordable (write once) access type optical disc, the DRM data may be placed at any position inside the program area, and the DRM pointer entry may be placed at any position after the DRM data. One method of retrieving DRM data stored on a disc is disclosed in European patent application 2004 / 021345A1, which is incorporated herein by reference. This document discloses a method of accessing digital rights management data stored inside a program area of a recording medium which is a recordable or rewritable disc. The proposed solution adds an entry to the disk so that the drive can find the DRM pointer entry (ALP), providing the DRM data stored on the disk.

However, recording the KLA in a location different from the location specified in the sapphire project can delay the disc reading and playback of the content. In fact, if the KLA is not easily found at the designated location next to the ICB, the drive's operating system will first need to scan the entire disk before processing the stored content, which may take several minutes or hours. .

As mentioned above, the UDF standard imposes a condition on the location of the ICB on the disk, and current standardization attempts tend to impose a condition on the location of the KLA. Thus, these main requirements need to be met at the same time. Since the ICB becomes the last recorded sector of the program area and the KLA is placed near this, such a configuration works well at the time of reading. Problems arise when KLA records occur. In fact, in host / drive optics, both the host and the drive are responsible for writing data, but none are under control when using general purpose UDF support. Therefore, there is a need to define other recording mechanisms that can meet both the UDF standard and the sapphire specification, or other specifications that can impose the same restrictions on DRM data without affecting the overall structure of the disc.

After all, it is an object of the present invention to provide a solution that satisfies both the universal file system defined in the UDF and the standards that can impose conditions on DRM-related data.

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

In order to achieve the above object, a method of storing data on a recording medium of the above-mentioned kind is provided. The method includes a first step in which the data set last written to the main program memory area of the disc is stored in the memory of the drive. Thereafter, digital rights management data is recorded in the main program memory area. This DRM data may control access to protected content stored on the record carrier. When the DRM data is recorded on the disk, the data set that was stored in the memory of the drive is again sequentially written after the DRM data in the main program memory area.

The present invention temporarily stores the last recorded sector in the memory of the drive, during which data related to digital rights management is recorded on the disc. Then, the data temporarily stored in the memory is written again next to the DRM data on the disk. Therefore, when the data temporarily stored in the memory of the drive is ICB, the present invention advantageously solves the problem encountered. In fact, if the medium is UDF compliant, the last recorded sector will actually contain the ICB and the virtual allocation table. According to this, the present invention ensures that the ICB is the last last recorded sector on the disc, and ensures that the DRM data is written sequentially next to it.

In an exemplary embodiment of the present invention, the method is performed upon request of recording DRM data on the medium. Such a request may be subject to other commands, such as a release command, a stop command, or the like, or may be generated based on the need for such a request to update the DRM data. For example, the system may be set so that the DRM data is automatically updated when an update has been waiting in the drive for a predetermined period or when the number of waiting updates is greater than the threshold. The recording of the DRM data may be started by stopping the drive or by the medium ejected from the drive.

Moreover, the present invention relates to a disc drive having a storage space into which a recording medium can be inserted. The recording medium may be an optical disk having a UDF defined structure consisting of a lead-in memory area, a main memory area and a lead-out memory area. The apparatus further includes a storage device and control means configured to control the recording of data on the recording medium. The apparatus of the present invention is configured such that the control means controls the storage of the data set last recorded in the main program memory area in the storage device. Then, the control means controls the recording of data related to digital rights management in the main program memory area. Such data defines rules relating to access to content on the record carrier. The control means further controls the recording of the data set stored in the storage device into the main program memory area.

The above and other inventions of the present invention will become more apparent with reference to the embodiments described below.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings in which:

1 illustrates a media / drive system of the present invention,

2A, 2B and 2C show the layout of the medium of the present invention.

1 shows a block diagram of a playback system 100 in accordance with the present invention. In order to read the user data from the disc 102, a reading unit 104 is provided. Alternative agreements exist between content providers and industrial players to develop digital rights management (DRM) systems that define usage restrictions on some or all of the user data. This means that the content stored on disk 102 may be encrypted, and the disk may store cryptographic keys used to decrypt the content before the user processes the content. Moreover, for example, a license may be stored on disk 102 that indicates whether the user is allowed to make copies of the content. These licenses and keys are called DRM data. A reading unit 104 is further provided for reading such DRM data. However, it is necessary to find the pointers pointing to the DRM data first, and the reading unit 104 has an evaluation unit for performing this. Once the evaluator inside the readout 104 locates the DRM pointer, the DRM data is given to the control block 114 via the lead 206. The control block 114 is in a digital signal processing unit (DSP) 110 which serves to process content and format specific data on the disk 102 when the content is recorded on or played on the disk 102. Is placed. The read DRM data is used to control the output of the user data, i.e., the control section 114 prohibits the output of the output signal OUT, for example, when the license prohibits the output, or before the data is reproduced to the user. By enabling decoding, the content reproducing unit 112 of the DSP 110 is controlled. The present invention is in no way limited to license and key cryptographic mechanisms as described above, but also includes control of other usage restrictions or other terminations on content access or processing.

The playback system 100 of FIG. 1 can accept recordable discs, and therefore further includes a recording unit 108 for recording content on the disc 102. As shown in FIG. The disc 102 is a CD-R based on the Orange Book Part II specification, i.e. the disc 102 is a write once type, but the general principles of the present invention may be applied to other types of optical storage media that are rewritable discs. For example, the present invention also relates to future Blu-ray Discs, specifically BD-R and DVD + R / -R.

The data IN given to the input of the DSP unit 110 is transmitted to the recording unit 108 via the conductive line 204. The DSP may control the manner in which the recording unit 108 writes the data IN on the disc 102 via the control line 202. The DSP 110 may control the recording on the disk 102 of data obtained from the storage device 106 of the system 100 as described later.

The playback system further includes a storage device 106 that stores content, user data, and data specific to the format associated with the disk 102. Memory 106 may include a temporary memory portion that stores a data set with a short life cycle, that is, a data set that may be removed after a read or write cycle, or as soon as the inserted disc 102 is ejected. have. The storage device 106 may also include permanent storage portions for permanent storage of user and standard-specific data and contents, whether or not erasable.

In this exemplary embodiment, the system 100 is based on UDF and sapphire. As a result, the system 100 and the disk 102 satisfy the above requirements. Thus, to ensure that the ICB block is inside the last recorded sector and that the KLA is next to the ICB, the system 100 operates as follows.

System 100 may be designed to automatically activate the recording of KLA data in certain situations. The recording of the KLA may be initiated in two ways. In the first case, the recording unit 108 sends a command to the application in charge of recording the content on the disk 102 to record the KLA. This application may run inside the DSP 110 or outside the system 100. The recording command may be part of the recording procedure, for example ending the recording of the content on the disc 102. Thus, whenever the DSP 110 controls the recording of a data set secured by the associated DRM rights, the recording process eventually entails instructions to record the KLA data indicating the DRM rights. The KLA data may be received with the content to be recorded on the disc 102 or may be stored in the storage 106 beforehand and obtained from this storage. In addition, the DSP 110 may issue a write command when an update to be progressed of the KLA data temporarily stored in the storage device 106 has been delayed for too long. Update of KLA on disk 102 may occur at regular time intervals.

Alternatively, KLA data is recorded upon ejection of the disk 102 in the system 100. The DSP 110 tracks whether the KLA cached in the storage 106 has changed. The KLA changes when the content is recorded or when the reading unit 104 reads the content from the disc 102. For example, the right to watch a movie may limit the user's maximum number of views. Therefore, when viewing the content, the KLA data associated with the movie is stored in the storage device 106 and updated. The foregoing is given by way of example only, and the present invention also relates to a system in which the reading process does not necessarily involve a change in the KLA. As a result, when the disk 102 is ejected or the system 100 is turned off in response to the external command COM, the system DSP 110 checks whether the update of the KLA data is waiting in the storage 106, Modify the KLA on disk 102 accordingly before ejecting or powering off the disk.

The recording or updating of a KLA may begin under certain circumstances as described above, but the invention includes other situations not mentioned herein that may result in the recording of a KLA.

2A, 2B and 2C show the structural format of the disc 102 defined by the UDF standard at three instants. The disc 102 includes a lead-in portion 402, a main program memory region 404, and a lead-out portion 406. The lead-in and lead-out portions are reserved areas on the disc 102 and have not been recorded yet. In FIG. 2A, the recording unit 108 recorded the data set 408 in the main program area of the disc 102. Since the system 200 is UDF compliant, when recording a data set on the disk 102, the recording unit 108 later records the VAT ICB related to the main program memory area of the disk 102. In the following operation, one of the above situations is required to record the KLA on the disk 102. Thereafter, the DSP 110 controls the reading unit 104 to copy the last recorded data block from the disk 102 to the storage device 106. At this moment as shown in Fig. 2A, the last written block is the VAT ICB. The DSP 110 then controls the recording of the KLA on the disk 102 as shown in FIG. 2B, and then, in the next step, cache from the storage 106 to the program memory area of the disk 102. The recording of the VAT ICB stored in the control is controlled. As a result, the structure of the disk 102 is as shown in Fig. 2C, so that the last recorded sector is still the VAT ICB, and the DRM data contained in the KLA is stored next to the VAT ICB in the program area. Thus, an advantage of one or more embodiments is that it can enable quick retrieval of DRM pointers and data included in a KLA while complying with the UDF standard. The present invention makes it possible to add digital rights management to an optical disc without changing the specific parts of the software and hardware of the system 100, and the present invention only changes the optical drive.

Claims (10)

A method of storing data in a record carrier 102 comprising a main program memory area 404, Storing in the memory 106 of the drive the data set last recorded in the main program memory area of the disc; Recording digital rights management data (KLA) in said main program memory area for controlling access to content on a recording medium; And recording the data set stored in the memory of the drive next to the digital rights management data on the main program memory area. The method of claim 1, Wherein said storing and recording steps are performed in response to a request to record digital rights management data generated in a drive. The method of claim 2, And the request is initiated by an eject command to eject the disc from the drive. The method of claim 2, And the request is invoked when the pending update count of the digital rights management data is greater than a threshold. The method of claim 2, And the request is invoked based on a period during which an update has been awaited. The method of claim 1, Storage in the memory of the drive occurs simultaneously with recording of the data set in the program memory area of the disk. The method of claim 1, Storing of the data set in the memory of the drive comprises copying the data set from the main program memory area. The method of claim 1, And said data set is an information control block associated with a virtual allocation table stored on said disk. The method of claim 1, And the digital rights management data is stored in a keylocker area defined in the sapphire specification. A storage space for storing a recording medium including a main program memory area; Memory, An apparatus comprising control means (108, 110) configured to control the recording of data on the recording medium, The control means is adapted for storing the data set last recorded in the main program memory area in the storage device 106 and thereafter for the data related to digital rights management for controlling access to content on the recording medium 102. Controlling recording to a main program memory area and further controlling recording of a data set stored in the storage to the main program memory area.

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